ICINCO 2014 Abstracts
Area 1 - Intelligent Control Systems and Optimization
Full Papers| Paper Nr: | 29 |
| Title: | Efficient In-flight Transfer Alignment Using Evolutionary Strategy Based Particle Filter Algorithm |
| Authors: | Suvendu Chattaraj and Abhik Mukherjee |
| Abstract: | Large initial misalignment between mother and daughter munitions make transfer alignment system nonlinear, because small angle approximation applicable to the system dynamics does not hold. Further, when the parameters of state transition matrix are based on current measurements, the system becomes time varying. A conventional Kalman filter fails to estimate misalignment in such situations. A particle filter performs satisfactorily, but, the performance suffers when the knowledge about the system is not accurate. Out of particles that get propagated through such improper system dynamics, only a few are retained and used for estimation purpose, due to sample impoverishment problem. In this work, it is claimed that better result can be obtained by employing an evolutionary strategy. Set of support points are generated for each particle by propagating the particle through an array of perturbed system dynamics, and, then by choosing best weight support point as apriori estimate from that set. The current work considers design of such evolutionary strategy based particle filter. For the purpose of proving robustness of proposed algorithm, simulation is first carried out on target tracking problem. Then it is applied to in-flight transfer alignment problem and its performance is found to be satisfactory. |
| Paper Nr: | 38 |
| Title: | Optimal Feedback Control for a Perimeter Traffic Flow at an Urban Region |
| Authors: | Jack Haddad and Ilya Ioslovich |
| Abstract: | Traffic flow control has motivated many researchers since early decades of the 19th century. Recently, the concept of a perimeter traffic control for an urban region has been strengthened by a series of works, which have shown that a perimeter controller, located at a region border, can manipulate the transfer flows across the border to maximize the total outflow of the region. The macroscopic fundamental diagram (MFD), that relates average flow with accumulation, is used to model the traffic flow dynamics in the region. Assuming that the control inputs of the cross-border flows are coupled, i.e. the border is always utilized over time for transferring flows by one of the two directions (from and towards the region), and that the urban region has two traffic flow demands generated inside the region with internal and external destinations, and a generated traffic flow outside the region with a destination to the region, the explicit formulation of the optimal feedback control policy and a proof of optimality are provided. The proof is based on the modified Krotov-Bellman sufficient conditions of optimality, where the upper and lower bounds of state variables are calculated. |
| Paper Nr: | 108 |
| Title: | Means for Finding Meaningful Levels of a Hierarchical Sequence Prior to Performing a Cluster Analysis |
| Authors: | David Allen Olsen |
| Abstract: | When the assumptions underlying the standard complete linkage method are unwound, the size of a hierarchical sequence reverts back from n levels to n(n-1)/2 +1 levels, and the time complexity to construct a hierarchical sequence of cluster sets becomes O(n^4). Moreover, the post hoc heuristics for cutting dendrograms are not suitable for finding meaningful cluster sets of an n(n-1)/2 +1-level hierarchical sequence. To overcome these problems for small-n, large-m data sets, the project described in this paper went back more than 60 years to solve a problem that could not be solved then. This paper presents a means for finding meaningful levels of an n(n-1)/2 +1-level hierarchical sequence prior to performing a cluster analysis. By finding meaningful levels of such a hierarchical sequence prior to performing a cluster analysis, it is possible to know which cluster sets to construct and construct only these cluster sets. This paper also shows how increasing the dimensionality of the data points helps reveal inherent structure in noisy data. The means is theoretically validated. Empirical results from four experiments show that finding meaningful levels of a hierarchical sequence is easy and that meaningful cluster sets can have real world meaning. |
| Paper Nr: | 143 |
| Title: | Clustering of Emotional States under Different Task Difficulty Levels for the Robot-assisted Rehabilitation system-RehabRoby |
| Authors: | Yigit Can Aypar, Yunus Palaska, Ramazan Gokay, Engin Masazade, Duygun Erol Barkana and Nilanjan Sarkar |
| Abstract: | In this paper, we study an unsupervised learning problem where the aim is to cluster the emotional state (excitedness, boredom, or stress) using the biofeedback sensor data while subjects perform tasks under different difficulty levels on the robot assisted rehabilitation system-RehabRoby. The dimension of the training vectors has been reduced by using the Principal Component Analysis (PCA) algorithm after collecting the biofeedback sensor measurements from different subjects under different task difficulty levels to better visualize the sensor data. The reduced dimension vectors are fed into a K-means clustering algorithm. Numerical results have been given to demonstrate that for each training vector, the emotional state decided by the clustering algorithm is consistent with the subjects declaration of his/her emotional state obtained via surveys after performing the task. |
| Paper Nr: | 176 |
| Title: | Reconfigurable Priority Ceiling Protocol - Under Rate Monotonic Based Real-time Scheduling |
| Authors: | Maroua Gasmi, Olfa Mosbahi, Mohamed Khalgui and Luis Gomes |
| Abstract: | This research paper deals with reconfigurable real-time systems to be adapted to their environment under user requirements. A reconfiguration scenario is a run-time software operation that allows the addition, removal and update of real-time OS tasks which can share resources and should meet corresponding deadlines. We propose a new Reconfigurable Priority Ceiling Protocol (denoted by RPCP) that avoids deadlocks after any reconfiguration scenario and changes the priorities of tasks in order to reduce their response and blocking times, and to meet their deadlines. This protocol requires the use of two virtual processors in order to guarantee the non-interruption of execution during the reconfiguration step. We develop a tool that encodes this protocol which is applied to a case study. |
| Paper Nr: | 186 |
| Title: | Genetic Programming Applied to Biped Locomotion Control with Sensory Information |
| Authors: | César Ferreira, Pedro Silva, João André, Cristina P. Santos and Lino Costa |
| Abstract: | Generating biped locomotion in robotic platforms is hard. It has to deal with the complexity of the tasks which requires the synchronization of several joints, while monitoring stability. Further, it is also expected to deal with the great heterogeneity of existing platforms. The generation of adaptable locomotion further increases the complexity of the task. In this paper, Genetic Programming (GP) is used as an automatic search method for motion primitives of a biped robot, that optimizes a given criterion. It does so by exploring and exploiting the capabilities and particularities of the platform. In order to increase the adaptability of the achieved solutions, feedback pathways were directly included into the evolutionary process through sensory inputs. |
| Paper Nr: | 191 |
| Title: | Aggregated Performance and Qualitative Modeling Based Smart Thermal Control |
| Authors: | Afef Denguir, Francois Trousset and Jacky Montmain |
| Abstract: | In order to ensure thermal energy efficiency and follow government’s thermal guidance, more flexible and efficient buildings’ thermal controls are required. This paper focuses on proposing an efficient, scalable, reusable, and data weak dependent smart thermal control approach based on an aggregated performance and imprecise knowledge of buildings’ thermal specificities. Its main principle is to bypass data unavailability and quantitative models identification issues and to ensure an immediate thermal enhancement. For this, we propose, first, an aggregated performance based smart thermal control in order to identify relevant thermal setpoints. An extended thermal qualitative model is then introduced to guarantee an efficient achievement of the identified thermal setpoints. Uncertainty about how relevant a thermal control is for a given thermal situation is thus reduced using online and preference based learnings. |
| Paper Nr: | 193 |
| Title: | A Hybrid Metaheuristic Approach to Optimize the Content Transmission in Multimedia Systems |
| Authors: | Arthur T. Gómez, Luan C. Nesi, Marcio G. Martins and Leonardo D. Chiwiacowsky |
| Abstract: | The advent of the digital television in Brazil has allowed users to access interactive channels. Once interactive channels are available, the users are able to find multimedia content such as movies and breaking news programs, to send and/or receive emails, to access interactive applications and also other contents. In this context, a high demand of requests from users is expected. Therefore, from the content provider's point of view, the determination of transmission parameters is needed in order to ensure the best quality of transmission to every user. The aforementioned identification problem is modelled as an optimization problem and a solution procedure based on metaheuristic techniques is proposed. Genetic Algorithm and Tabu Search metaheuristics are employed separately and coupled in a hybrid scheme to define the best transmission policy, optimizing the transmission parameters, such as audio and video transmission rates. Based on the experimental results, the hybrid algorithm has produced better solutions which meet the quality requirements. |
| Paper Nr: | 201 |
| Title: | Hand-projector Self-calibration Using Structured Light |
| Authors: | Christian Sebastian Wieghardt and Bernardo Wagner |
| Abstract: | This paper describes two methods for determining the extrinsic calibration parameters of a projector with respect to the robot hand. One of them simultaneously solves the transformation between a camera with respect to the robot base. Self-calibration means that no sort of calibration rig like a chessboard is needed. Since the projector has no exteroceptive capabilities, a camera is placed in the environment or rigidly attached to the robot base to detect the projected pattern. At different robot configurations correspondences between the camera and projector are established to recover the transformation between them up to an unknown scale factor. The common known formulations AX = XB and AX = ZB can be arranged in a linear form with respect to the unknown extrinsic parameters and scale factors, and solved in least square sense. |
| Paper Nr: | 205 |
| Title: | Adaptive Embedded Systems - New Composed Technical Solutions for Feasible Low-Power and Real-time Flexible OS Tasks |
| Authors: | Hamza Chniter, Mohamed Khalgui and Fethi Jarray |
| Abstract: | The paper deals with low-power adaptive scheduling of synchronous and flexible real-time OS tasks. A software reconfiguration scenario is assumed to be any run-time operation allowing the addition-removal-update of OS tasks to adapt the system to its environment under well-defined conditions. The problem is that any reconfiguration can push the system to an unfeasible behavior where temporal properties are violated or the energy consumption is possibly high and unacceptable. A task in the system can change its characteristics at any time when a reconfiguration scenario is applied, it can also be stopped or replaced by another one. The difficulty is how to find the new temporal parameters of the systems tasks after any reconfiguration. We use a DVS processor which is with a variable speed to support run-time solutions that re-obtain the system’s feasibility. The challenge is how to compute the best combinations between available processor speeds for a good compromise between execution time and energy consumption. We propose a combinatorial optimization method based on integer programming and heuristics. We propose also a solution when the available speeds do not allow the feasibility of the system. Both approaches include a mechanism to adjust the deadlines of tasks to satisfy the feasibility conditions and overcome the problem of rejected tasks. This mechanism makes the scheduling more flexible and able to react in accordance with its environment. |
| Paper Nr: | 256 |
| Title: | Reactive Reaching and Grasping on a Humanoid - Towards Closing the Action-Perception Loop on the iCub |
| Authors: | Jürgen Leitner, Mikhail Frank, Alexander Förster and Jürgen Schmidhuber |
| Abstract: | We propose a system incorporating a tight integration between computer vision and robot control modules on a complex, high-DOF humanoid robot. Its functionality is showcased by having our iCub humanoid robot pick-up objects from a table in front of it. An important feature is that the system can avoid obstacles – other objects detected in the visual stream – while reaching for the intended target object. Our integration also allows for non-static environments, i.e. the reaching is adapted on-the-fly from the visual feedback received, e.g. when an obstacle is moved into the trajectory. Furthermore we show that this system can be used both in autonomous and tele-operation scenarios. |
| Paper Nr: | 260 |
| Title: | Adaptive Control of Position Compensation for Cable-Conduit Mechanisms Used in Flexible Surgical Robots |
| Authors: | T. N. Do, T. Tjahjowidodo, M. W. S. Lau and S. J. Phee |
| Abstract: | Natural Orifice Transluminal Endoscopic Surgery (NOTES) is a method that allows for performing complex operations via natural orifices without skin incisions. Its main tool is a flexible endoscope. Cable-Conduit Mechanisms (CCMs) are often used in NOTES because of its simplicity, safety in design, and easy transmission. Backlash hysteresis nonlinearities between the cable and the conduit pose difficulties in the motion control of the NOTES system. It is challenging to achieve the precise position of robotic arms when the slave manipulator inside the humans body. This paper presents new approaches to model and control for pairs of CCMs. It is known that the change of cable-conduit configuration will affect the backlash hysteresis nonlinearities. To deal with such change, a new nonlinear and adaptive control scheme will be introduced. The backlash hysteresis parameters are online estimated under the assumption of availability of output feedback and unknown bound of nonlinear parameters. To validate the proposed approach, a prototype of single-DOF-Master-Slave system, which consists of a master console, a telesurgical workstation, and a slave manipulator, is also presented. The proposed compensation scheme is experimentally validated using the designed system. The results show that the proposed control scheme efficiently improves the tracking performances of the system regardless of the change of endoscope configuration. |
Short Papers
| Paper Nr: | 30 |
| Title: | Quantification of Information Uncertainty for the Purpose of Condition Monitoring |
| Authors: | Pavel Ettler and Kamil Dedecius |
| Abstract: | Pervasive uncertainty of information which affects to some extent functionality of every control and information system concerns naturally the condition monitoring systems as well. Uncertainty can practically be disregarded when monitoring a single component, but it should be taken into account when compounding extensive amount of information within a hierarchical diagnostic system. When using uncertain information for expression of inner system's relations, probabilistic and namely subjective logic may do a good turn. However, the key problem remains how to quantify the uncertainty on the lowermost level of the monitoring system. The paper introduces several solutions based on inspection of either a single measured signal or a couple of correlated signals. |
| Paper Nr: | 31 |
| Title: | Hierarchical Modelling of Industrial System Reliability with Probabilistic Logic |
| Authors: | Kamil Dedecius and Pavel Ettler |
| Abstract: | The use of Bayesian methods in dynamic assessment of system reliability is inevitably limited by computational difficulties arising from non-conjugate prior distributions. This contribution proposes an alternative framework, based on the combination of Bayesian methods and the subjective logic. The advantage of the former – consistent and exhaustive representation of available statistical knowledge, is extended by the latter, allowing computationally feasible combination of this knowledge at any level of the observed system using logic operations. The resulting methodology is currently under development in order to enlarge the capability of an intended novel industrial hierarchical condition monitoring system. |
| Paper Nr: | 41 |
| Title: | Describing Functionalities and Reactions of Cars and Managing Their Feature Interactions |
| Authors: | Ahmed Khoumsi and Zohair Chentouf |
| Abstract: | We develop an Automotive Reaction System (ARS) framework to support cars by capabilities to react to various situations. With ARS, the states and actions of a car are designed as objects of a high level objectoriented language, called ARS-language. ARS permits also to design the reactions of a car to various situations by an ARS-specification consisting of rules “condition->action”. The ARS-objects and ARSspecification are implemented in a car to provide her with capabilities to function and react online. ARS permits also to model certain actions of a car at a high abstraction level by an ARS-model consisting of rules “condition->operation”. With ARS, we are confronted to conflicts (or feature interactions) which denote situations where an ARS-specification implies simultaneous executions of incompatible actions. We propose an approach to detect and resolve feature interactions. |
| Paper Nr: | 47 |
| Title: | Fuzzy Controller based on PLC S7-1200 - Application to a Servomotor |
| Authors: | Isaías González Pérez, A. José Calderón Godoy and Manuel Calderón Godoy |
| Abstract: | This paper presents the design and validation of a fuzzy logic controller implemented with an industrial programmable logic controller (PLC). The chosen device belongs to the S7-1200 series of Siemens, whereas the code has been developed in Ladder Diagram language using the software TIA Portal. The fuzzy controller is of Mamdani type and is applied to control the speed of a servomotor. A comparison with a Simulink/Matlab fuzzy controller is done to validate the developed software module and to show the feasibility of the PLC to manage this kind of control algorithm. |
| Paper Nr: | 55 |
| Title: | A Study for Automatic Diagnosing System of Parkinson Disease - A Systematic Analysis of Parkinsonian Tremor by Accelerometer |
| Authors: | Ichiro Fukumoto |
| Abstract: | New objective diagnosing methods of Parkinson Disease is proposed with 3 D accelerometers. A mathematical model based on the peripheral feedback theory is tested by computer simulation with good coincident with the clinical data. We have found the main frequency of Parkinsonian tremor is about 4Hz in arms comparing the one of physiological tremor (8Hz). Patients in L-Dopa treatment have been measured by the system that corresponds well to a parameter Fgk that indicates the fatigue of intrafusal muscle. Biofeedback training by sound and visual parameters are also proved with good tremor improvement in its main frequency and severity. |
| Paper Nr: | 59 |
| Title: | Prime - A Service-oriented Framework with Minimal Communication Overheads |
| Authors: | Sergey Zhigalov and Yuri Okulovsky |
| Abstract: | We present Prime, a framework for development of service-oriented control systems in robotics. Prime uses an original approach to services: the service is not a monolith, but is subdivided into three layers. This approach allows creating services’ internal logic without references to communication-related entities, and therefore almost without initial learning of Prime. In addition, Prime offers three methods of linking services together that are completely interchangeable and compatible. The first is a classic service-oriented solution; the second belongs more to functional programming, it combines the algorithms inside each service into one function, that is equivalent to the behavior of the service-oriented system. The third uses code emission technique to significantly increase the performance. The Prime adds little overheads and is much faster than, for example, Microsoft Robotics Studio. |
| Paper Nr: | 61 |
| Title: | A Steady State Sequence Entropy Model for Flow Controlled Multi-input Single-output Queues with Logical Constraints |
| Authors: | Anthony John Walker and Glen Bright |
| Abstract: | Clearing type flow control policies have been used extensively in mediating server access between multiple arrival processes. Although the stability and performance of clearing policies has been well formulated and studied in the literature, the growth in arrival to departure sequence disorder for each arriving job, across a serving resource, is still an area for further analysis. In this paper, a closed form model is formulated that characterises arrival to departure sequence disorder through stable flow controlled servers under clearing policy. Specifically addressed are the effects of sequence disorder imposed on a downstream server operating on the outputs of parallel upstream servers, under a downstream arrival synchronisation constraint. |
| Paper Nr: | 71 |
| Title: | A Study of the Efficiency of Hybridized Approaches Based on Particle Swarm Optimization Technique |
| Authors: | Houda Abadlia, Nadia Smairi and Kamel Zidi |
| Abstract: | Particle Swarm Optimization (PSO) is a continuous optimization metaheuristic in which the PSO’s convergence is ensured, but its solution is considered neither as a global solution nor as a local solution. The convergence is guaranteed only to the best visited position by the whole swarm. In this paper, we propose a couple of hybrid methods for multi-objective particle swarm optimization. In fact, we combined these methods in the following two cases: in the first case, we proposed to hybridize it with a local search technique based on Tabu Search (TS). In the second case, we proposed to hybridize it with a global search technique based on PESAII. The proposed mechanisms are validated using fifteen different functions from the specialized literature of multi-objective optimization. The obtained results show that using this kind of hybridization is justified as it is able to improve the quality of the solutions in the majority of cases. |
| Paper Nr: | 72 |
| Title: | Observer-based controller Design for Remotely Operated Vehicle ROV |
| Authors: | Adel Khadhraoui, Lotfi Beji, Samir Otmane and Azgal Abichou |
| Abstract: | This paper presents a method to design an observer-based controller that simultaneously solves global estimation of state and asymptotic stabilization of an underactuated remotely operated vehicle moving in the in three-dimensional. The vehicle does not have a sway and roll actuator and has only position and orientation measurements available. The control development is based on Lyapunov’s direct method for nonlinear system. |
| Paper Nr: | 73 |
| Title: | New Mechanisms to Enhance the Performances of an Adaptive Algorithm of Particle Swarm Optimization |
| Authors: | Ahlem Amor, Nadia Smairi and Kamel Zidi |
| Abstract: | The aim of this paper is to present an improvement of the multiobjective TRIBES (MO-TRIBES). The main idea of this improvement is to propose two new operators: a mutation, which is applied to good particles and four processes of resets, which are applied to bad particles. The aim of the integration of those mechanisms is to insure a good exploration and/or exploitation of the search space. Besides, in our study, we proposed different percentages to apply these operators. The mechanisms proposed are validated using ten different functions from specialized literature of multi-objective optimization. The obtained results show that using these operators is valid as it is able to improve the quality of the solutions in the majority of case. |
| Paper Nr: | 77 |
| Title: | Dimension Reduction with Coevolutionary Genetic Algorithm for Text Classification |
| Authors: | Tatiana Gasanova, Roman Sergienko, Eugene Semenkin and Wolfgang Minker |
| Abstract: | Text classification of large-size corpora is time-consuming for implementation of classification algorithms. For this reason, it is important to reduce dimension of text classification problems. We propose a method for dimension reduction based on hierarchical agglomerative clustering of terms and cluster weight optimization using cooperative coevolutionary genetic algorithm. The method was applied on 5 different corpora using several classification methods with different text preprocessing. The method reduces dimension of text classification problem significantly. Classification efficiency increases or decreases non-significantly after clustering with optimization of cluster weights. |
| Paper Nr: | 111 |
| Title: | Using Evolutionary Algorithms to Plan Automatic Minehunting Operations |
| Authors: | Nuno Abreu and Aníbal Matos |
| Abstract: | While autonomous underwater vehicles (AUVs) are increasingly being used to perform mine countermeasures (MCM) operations, the capability of these systems is limited by the efficiency of the planning process. In this paper we study the problem of multiobjective MCM mission planning with an AUV. In order to overcome the inherent complexity of the problem, a multi-stage algorithm is proposed and evaluated. Our algorithm combines an evolutionary algorithm (EA) with a local search procedure based on simulated annealing (SA), aiming at a more flexible and effective exploration and exploitation of the search space. An artificial neural network (ANN) model was also integrated in the evolutionary procedure to guide the search. The results show that the proposed strategy can efficiently identify a higher quality solution set and solve the mission planning problem. |
| Paper Nr: | 117 |
| Title: | Load-aware Reconfiguration of LTE-Antennas - Dynamic Cell-phone Network Adaptation Using Organic Network Control |
| Authors: | Sven Tomforde, Alexander Ostrovsky and Jörg Hähner |
| Abstract: | The utilisation of cell phone networks increases continuously, especially driven by the introduction of new mobile services and smart phones. Network operators can follow two directions to deal with the problem: either install new hardware or increase the efficiency of the existing infrastructure. This paper presents a novel algorithm to improve the efficiency of current networks by allowing for a self-organised load-dependent reconfiguration of antennas. The algorithm is capable of identifying hotspot traffic, assigning this to a neighbouring cell, and learning the best strategy at runtime. This leads to a self-improving intelligent control mechanism. The simulation-based evaluation results demonstrate the potential benefit, while simultaneously keeping the hardware’s deterioration at a comparable level. |
| Paper Nr: | 119 |
| Title: | BeeAdHocServiceDiscovery - A MANET Service Discovery Algorithm based on Bee Colonies |
| Authors: | Gianmaria Arenella, Filomena de Santis and Delfina Malandrino |
| Abstract: | In a mobile ad-hoc network, nodes are self-organized without any infrastructure support: they move arbitrarily causing the network to experience quick and random topology changes, have to act as routers as well as forwarding nodes, some of them do not communicate directly with each other. Routing, IP address auto-configuration and Web service discovery are among the most challenging tasks in the MANET domain. Swarm Intelligence is a property of natural and artificial systems involving minimally skilled individuals that exhibit a collective intelligent behaviour derived from the interaction with each other by means of the environment. Colonies of ants and bees are the most prominent examples of swarm intelligence systems. Flexibility, robustness, and self-organization make swarm intelligence a successful design paradigm for difficult combinatorial optimization problems. This paper proposes BeeAdHocServiceDiscovery a new service discovery algorithm based on a bee swarm labour that may be applied to large scale MANET with low complexity, low communication overhead, and low latency. Eventually, future research directions are established. |
| Paper Nr: | 144 |
| Title: | A Robust Real-time Image Algorithm for Moving Target Detection from Unmanned Aerial Vehicles (UAV) |
| Authors: | Mathieu Pouzet, Patrick Bonnin, Jean Laneurit and Cedric Tessier |
| Abstract: | We propose a real time method for moving target detection from a camera embedded on a UAV. As the camera is moving, we must estimate the background motion in order to compensate it and then perform the moving target detection. This compensation is realized by an image registration method. For this, we use an hybrid method using global minimization and feature-based approaches, with a pyramidal implementation. The good results obtained for registration give us the potential moving targets. As some wrong detections still appear, due to noise, occlusions or local change of illuminations, we worked on a robust spatio-temporal tracker able to decide if potential targets are real moving targets or not. The algorithm must reach real time performances for VGA images at 30 fps with a standard PC. We have tested our method on different sequences and show the good results obtained thanks to the high precision in the image registration and the spatio-temporal tracker. |
| Paper Nr: | 161 |
| Title: | Document Clustering Using Multi-Objective Genetic Algorithms with Parallel Programming Based on CUDA |
| Authors: | Jung Song Lee, Soon Cheol Park, Jong Joo Lee and Han Heeh Ham |
| Abstract: | In this paper, we propose a method of enhancing Multi-Objective Genetic Algorithms (MOGAs) for document clustering with parallel programming. The document clustering using MOGAs shows better performance than other clustering algorithms. However, the overall computation time of the MOGAs is considerably long as the number of documents increases. To effectively avoid this problem, we implement the MOGAs with General-Purpose computing on Graphics Processing Units (GPGPU) to compute the document similarities for the clustering. Furthermore, we introduce two thread architectures (Term-Threads and Document-Threads) in the CUDA (Compute Unified Device Architecture) language. The experimental results show that the parallel MOGAs with CUDA are tremendously faster than the general MOGAs. |
| Paper Nr: | 169 |
| Title: | Navigation of an Autonomous Mobile Robot Using Data Association Method |
| Authors: | Amir Monjazeb, Jurek Z. Sasiadek and Dan Necsulescu |
| Abstract: | This paper presents an investigation on the performance of Unscented HybridSLAM using two different mapping strategies. The global map estimation using Unscented Kalman Filter is scrutinized for different scenarios, with and without the influence of a data association process. The accuracy of generated global map under different vehicle speed settings and with different process time is demonstrated using computer simulation. Results are discussed in terms of Root Mean Square (RMS) position error, orientation error, and time of navigation process. Results show that depending on the application, and on a desired speed, a compromise has to be done to get the best efficacy. |
| Paper Nr: | 177 |
| Title: | Multi Focus Image Fusion by Differential Evolution Algorithm |
| Authors: | Veysel Aslantas and Ahmet Nusret Toprak |
| Abstract: | In applications of imaging system one of the major problems is the limited depth of field which disallow to obtain all-in-focus image. However, microscopic and photographic applications desire to have all-in-focus images. One of the most popular ways to obtain all-in-focus images is the multi focus image fusion. In this paper a novel spatial domain multi focus image fusion method is presented. The method, firstly, calculates point spread functions of the source images by using a technique based on differential evolution algorithm. Then the fused image is constructed by using these point spread functions. Furthermore, the proposed method and other well-known methods are compared in terms of quantitative and visual evaluation. |
| Paper Nr: | 181 |
| Title: | Fuzzy Rule Bases Automated Design with Self-configuring Evolutionary Algorithm |
| Authors: | Eugene Semenkin and Vladimir Stanovov |
| Abstract: | Self-configuring evolutionary algorithm of fuzzy rule bases automated deign for solving classification problems, which combines Pittsburgh and Michigan approaches, is introduced. The evolutionary algorithm is based on the Pittsburgh approach where every individual is a rule base and the Michigan approach is used as a mutation operator. A self-configuration method is used to adjust probabilities of the usage of selection, mutation and Michigan part operators. Testing the algorithm on a number of real-world problems demonstrates its efficiency comparing to several other commonly used approaches. |
| Paper Nr: | 183 |
| Title: | Quadrupedal Locomotion Based in a Purely Reflex Controller |
| Authors: | César Ferreira, Vitor Matos, Cristina P. Santos and Auke Ijspeert |
| Abstract: | Quadruped locomotion in irregular and unknown terrains is still a problem to solve. The concept of reflexes is used in this work to contribute for the continuous search of answers about this theme. Biological researches show that spinal reflexes are crucial for a successful locomotion in the most varied terrains, so robotics investigation in this area could be a great advance in the robot’s locomotion. In this work, we present a sensory driven reflex controller, capable of generating locomotion in a quadruped compliant robot. This controller is totally dependent on sensory information, so the robot’s movements are the result of the robot interactions with the environment. Results show that the proposed controller is capable of generating movements in a flat terrain and is resilient to unexpected perturbations such as a small ramp. |
| Paper Nr: | 198 |
| Title: | Multi-agent Control Approach for Autonomous Mobile Manipulators - Determination of the Best Footsteps Combination |
| Authors: | Messous Mohamed Ayoub, Hentout Abdelfetah and Bouzouia Brahim |
| Abstract: | This paper presents our ongoing efforts toward the development of a distributed multi-agent framework for autonomous control of mobile manipulators. The proposed scheme assigns a reactive agent (Joint agent) to control each articulation of the manipulator, a hybrid agent (Mobile base agent) for the control of the mobile base, and a Supervisory agent to coordinate and synchronize the work of all the precedent agents. Each Control agent implements a Simulation-verification technique, in order to optimize, locally and independently from the other agents, the value of a predefined Objective function (fObj). The paper illustrates, also, the methodology we have followed to determine the best combination among possible footsteps for the Control agents of the system. This combination will be the input, among others, of the procedure seeking the optimal solution bringing the position of the end-effector of the mobile manipulator as close as possible to the imposed Target position. For this aim, different simulation scenarios are described and carried out, with and without considering breakdowns of some articulations of the manipulator or the mobile base. For the evaluation of the obtained solutions and the selection of the best footsteps combination, we have considered two criteria (i) fObj values and (ii) the number of iterations. |
| Paper Nr: | 214 |
| Title: | Reconfigurable CAN in Real-time Embedded Platforms |
| Authors: | Imen Khemaissia, Olfa Mosbahi and Mohamed Khalgui |
| Abstract: | This paper deals with the dynamic reconfiguration of the frame packing as well as the traffic of real-time packets on a CAN network. This network is assumed to link distributed reconfigurable STM32F4 microcontrollers that can automatically add-remove-update periodic and aperiodic OS tasks at run-time. These tasks may exchange messages to be loaded in packets and to be sent on the network. After the addition of a pair of dependent tasks on two microcontrollers, a message should be added on CAN and should respect a corresponding deadline related to these tasks. After several additions of messages, some deadlines may be violated and the CAN may not support the added messages. In addition, the frame packing should be adapted at run-time to any reconfiguration scenario in the different microcontrollers. We propose a multi-agent based architecture to check the correct transmission of messages. If some deadlines are violated, these agents propose technical solutions for the feasibility of the whole system. They can suggest first the modification of periods or deadlines of tasks and messages. They can propose also the removal of some OS tasks or messages from the controllers according to their priorities. We propose in addition new solutions to construct the dynamic frame-packing while the bandwidth is minimized. A tool is developed at LISI and Cynapsys to support the different contributions of this paper. |
| Paper Nr: | 228 |
| Title: | New Solutions for Fault Detections and Dynamic Recoveries of Flexible Power Smart Grids |
| Authors: | Syrine Ben Meskina, Narjes Doggaz and Mohamed Khalgui |
| Abstract: | This research paper deals with fault detections and dynamic recoveries of electrical smart grids that should be flexible and automatically adapted at run-time when faults occur on lines or devices. These grids are composed of three levels of power lines: High Voltage Lines (44KV), Medium Voltage Lines (11KV), and Low Voltage Lines (380V). In order to control the complexity of detection and deduction, we propose new relations between faults. We define also a multi-agent architecture to allow dynamic recoveries where two types of agents are defined: static agents and mobile agents. Static agents have as a task the detection of local faults on power lines and the recovery of their normal behaviors by using a local knowledge-base. The mobile agents are created to dynamically move on lines and to find new solutions when no local solution is found. To validate and test our approach, we present experimental results showing the originality of the paper’s contribution by assuming a case study. |
| Paper Nr: | 229 |
| Title: | A Self-adaptive Iterated Local Search Algorithm on the Permutation Flow Shop Scheduling Problem |
| Authors: | Xingye Dong, Maciek Nowak, Ping Chen and Youfang Lin |
| Abstract: | Iterated local search (ILS) is a simple, effective and efficient metaheuristic, displaying strong performance on the permutation flow shop scheduling problem minimizing total flow time. Its perturbation method plays an important role in practice. However, in ILS, current methodology does not use an evaluation of the search status to adjust the perturbation strength. In this work, a method is proposed that evaluates the neighborhoods around the local optimum and adjusts the perturbation strength according to this evaluation using a technique derived from simulated-annealing. Basically, if the neighboring solutions are considerably worse than the best solution found so far, indicating that it is hard to escape from the local optimum, then the perturbation strength is likely to increase. A self-adaptive ILS named SAILS is proposed by incorporating this perturbation strategy. Experimental results on benchmark instances show that the proposed perturbation strategy is effective and SAILS performs better than three state of the art algorithms. |
| Paper Nr: | 230 |
| Title: | Robot Trajectory Optimization for the Relaxed End-effector Path |
| Authors: | Sergey Alatartsev, Anton Belov, Mykhaylo Nykolaychuk and Frank Ortmeier |
| Abstract: | In this paper we consider the trajectory optimization problem for the effective tasks performed by industrial robots, e.g., welding, cutting or camera inspection. The distinctive feature of such tasks is that a robot has to follow a certain end-effector path with its motion law. For example, welding a line with a certain velocity has an even influence on the surface. The end-effector path and its motion law depend on the industrial process requirements. They are calculated without considering robot kinematics, hence, are often “awkward” for the robot execution, e.g., cause high jerks in the robot’s joints. In this paper we present the trajectory optimization problem where the end-effector path is allowed to have a certain deviation. Such path is referred to as relaxed path. The goal of the paper is to make use of this freedom and construct the minimal-cost robot trajectory. To demonstrate the potential of the problem, jerk of the robot joint trajectory was minimized. |
| Paper Nr: | 243 |
| Title: | Multiobjective Optimisation by PSO for Switched Reluctance Motor (SRM) Drive |
| Authors: | Jayanta Mukherjee and Sumana Chowdhuri |
| Abstract: | Switched Reluctance Motor (SRM), which has many advantages like Induction machine exhibits very nonlinear characteristics and high torque ripple, the only disadvantages of this machine. Its torque ripple is dependent on the current profile and also on the turn on and turns off angle of phase excitation and the speed is dependent on the current command. This work presents one of the Heuristic approaches like Particle Swarm optimization (PSO) to determine the optimum proportional-integral (PI) controller parameters and turn on and turn off angles, for minimum torque ripple with optimum torque profile SRM drive. These offline tuning methods are implemented for the model of a SRM in MATLAB. It has been observed that by optimizing the controller parameters of a SRM drive with PSO the performance of the controller is improved. |
| Paper Nr: | 285 |
| Title: | A Parallel Hierarchical Finite State Machine Approach to UAV Control for Search and Rescue Tasks |
| Authors: | Vitor de Araújo, Ana Paula G. S. Almeida, Ciro T. Miranda and Flavio de Barros Vidal |
| Abstract: | The process of developing a system for an Unnamed Aerial Vehicle (UAV) control is a complex task that we should be able to implement a set of elaborated algorithms with specific features as fast response for non-linear inputs, fault tolerance and easy maneuvering procedures. These features define the reachability and quality of the UAV overall control system. In this position paper, we propose a solution for the UAV control process using a Parallel Hierarchical Finite State Machine (PHFSM) that results in a high level system including all features required by an complex UAV control to search and rescue tasks. Following in this approach we can achieve many improvements than other usual implementations. Initials simulation experiments, using data from a simple UAV model, indicate in direction that many issues can be solved by this approach. |
| Paper Nr: | 290 |
| Title: | Spacecraft Solar Arrays Degradation Forecasting with Evolutionary Designed ANN-based Predictors |
| Authors: | Maria Semenkina, Shakhnaz Akhmedova, Eugene Semenkin and Ivan Ryzhikov |
| Abstract: | The problem of forecasting the degradation of spacecraft solar arrays is considered. The application of ANN-based predictors is proposed and their automated design with self-adaptive evolutionary and bio-inspired algorithms is suggested. The adaptation of evolutionary algorithms is implemented on the base of the algorithms’ self-configuration. The island model for the bio-inspired algorithms cooperation is used. The performance of four developed algorithms for automated design of ANN-based predictors is estimated on real-world data and the most perspective approach is determined. |
Posters
| Paper Nr: | 28 |
| Title: | A Variable Structure Controller for a Class of Hyper-redundant Arms |
| Authors: | Decebal Popescu, Nirvana Popescu, Mircea Ivanescu and Dorin Popescu |
| Abstract: | The paper treats the control problem of a class of hyper-redundant robot constituted by a chain of continuum segments. The technological model basis is a central, long and thin, highly flexible and elastic backbone. The driving system is a decoupled one. The main parameters of the arm control are determined by the curvature and curvature gradient. The dynamic model is inferred. A sliding mode control system is used in order to achieve a desired shape of the arm. The stability of the closed loop control system is proven. Numerical simulations are also provided to verify the effectiveness of the presented approach. |
| Paper Nr: | 37 |
| Title: | Fire Detection Robot Navigation Using Modified Voting Logic |
| Authors: | Dan-Sorin Necsulescu, Adeel ur Rehman and Jurek Sasiadek |
| Abstract: | Autonomous robots can be equipped to detect potential threats of fire and find out the source while avoiding the obstacles during navigation. The proposed system uses Voting Logic Fusion to approach and declare a potential fire source autonomously. The robot follows the increasing gradient of light and heat to identify the threat and approach source. |
| Paper Nr: | 64 |
| Title: | Manifold Embedding based Visualization of Signals |
| Authors: | Hee Il Hahn |
| Abstract: | We address the problem of transforming statistically stationary waveform signals into their intrinsic geometries by embedding them into two or three dimensional space for the purpose of visualizing them. The graph Laplacian based manifold embedding algorithms basically generate geometries intrinsic to the signal characteristics under the conditions that it is smooth enough and sufficient number of patches are extracted from it. Especially, commute time is known to have the properties of shrinking the mutual distance between two points as the number of paths connecting them increases, which makes it possible to align the statistically different patches in the form of curves. Extensive experiment is conducted with speeches and musical instrumental sounds to investigate the relevance of the waveforms to their own inherent geometries. |
| Paper Nr: | 94 |
| Title: | Common Diagonal Stability of Second Order Interval Systems |
| Authors: | Bengi Yildiz, Taner Büyükköroğlu and Vakif Dzhafarov |
| Abstract: | In this paper for second order interval systems we obtain necessary and sufficient conditions for the existence of a common diagonal solutions to the Lyapunov (Stein) inequality. Hurwitz and Schur cases are considered separately. One necessary and sufficient condition is given for n × n interval family of Z-matrices. The obtained results also give diagonal solution in the case of existence. |
| Paper Nr: | 122 |
| Title: | Optimal Camera Placement based Resolution Requirements for Surveillance Applications |
| Authors: | Houari Bettahar, Yacine Morsly and Mohand Said Djouadi |
| Abstract: | In this paper, we focus on the problem of optimally placing a mixture of static and PTZ cameras based on the resolution requirement, this configuration will be useful later cameras planning. The static cameras used for detecting an object or an event, this result is used to select the best PTZ camera within the network to identify or recognize this moving object or event. In our work the monitoring area is represented by a grid of points distributed uniformly or randomly (S. Thrun, 2002), then using surface-projected monitoring area and camera sensing model we develop a binary integer programming algorithm. The results of the algorithm are applied successfully to a variety of simulated scenarios. |
| Paper Nr: | 131 |
| Title: | Multi-agent Cooperative Algorithms of Global Optimization |
| Authors: | Maxim Sidorov, Eugene Semenkin and Wolfgang Minker |
| Abstract: | In this paper we present multi-agent cooperative algorithms of global optimization based on a genetic algorithm, an evolution strategy and particle swarm optimization. Island and co-evolution approaches have been selected as a main scheme of cooperation. The proposed techniques have been implemented and evaluated on a set of 22 multivariate functions. We assert that the proposed techniques could achieve much higher results in terms of reliability and speed criteria than the performance of corresponding conventional algorithms (without cooperative schemes) with average parameters on 18 functions from the 22 selected for the evaluation procedure. Such advantages are much more observable with increasing dimensionality of functions. Furthermore, the performance of the suggested algorithms was even higher than the performance of conventional algorithms with the best parameters for 5 functions. |
| Paper Nr: | 155 |
| Title: | Input and State Constrained Nonlinear Predictive Control - Application to a Levitation System |
| Authors: | Joanna Zietkiewicz |
| Abstract: | The subject of the article concerns a constrained predictive control with feedback linearization (FBL) applied for multiple-input and multiple-output (MIMO) system. It relies on finding a compromise in every step between feasible and optimal linear quadratic (LQ) control by minimization of one variable. Behaviour of model signals in function of minimized variable is investigated, in order to assure the optimality of the solution. LQ control based applications for feedback linearized models do not meet the problem of choosing weights in linear quadratic cost function. That important problem is solved here by comparison of the cost function with that obtained for the linear approximated system in the operating point. That provides satisfactory behaviour and also justifies the simplified approach relied on minimization of only one variable for MIMO system. |
| Paper Nr: | 164 |
| Title: | Implementing an Adaptive Higher Level Observer in Trusted Desktop Grid to Control Norms |
| Authors: | Jan Kantert, Hannes Scharf, Sarah Edenhofer, Sven Tomforde, Jörg Hähner and Christian Müller-Schloer |
| Abstract: | Grid Computing Systems are examples for open systems with heterogeneous and potentially malicious entities. Such systems can be controlled by system-wide intelligent control mechanisms working on trust relationships between these entities. Trust relationships are based on ratings among individual entities and represent system-wide information. In this paper, we propose to utilise a normative approach for the system-level control loop working on basis of these trust values. Thereby, a normative approach does not interfere with the entities’ autonomy and handles each system as black box. Implicit rules already existing in the system are turned into explicit norms – which in turn are becoming mandatory for all entities. This allows the distributed systems to derive the desired behaviour and cooperate in reaction to disturbed situations such as attacks. |
| Paper Nr: | 168 |
| Title: | Closing the Loop on a Complete Linkage Hierarchical Clustering Method |
| Authors: | David Allen Olsen |
| Abstract: | To develop a complete linkage hierarchical clustering method that 1) substantially improves upon the accuracy of the standard complete linkage method and 2) can be fully automated or used with minimal operator supervision, the assumptions underlying the standard complete linkage method are unwound, evaluating pairs of data points for linkage is decoupled from constructing cluster sets, and cluster sets are constructed de novo. These design choices make it possible to construct only the cluster sets that correspond to select, possibly non-contiguous levels of an n(n-1)/2 + 1-level hierarchical sequence. To construct meaningful cluster sets without constructing an entire hierarchical sequence, a means that uses distance graphs is used to find meaningful levels of such a hierarchical sequence. This paper presents an approach that mathematically captures the graphical relationships that are used to find meaningful levels and integrates the means into the new clustering method. The approach is inexpensive to implement. Consequently, the new clustering method is self-contained and incurs almost no extra cost to determine which cluster sets should be constructed and which should not. Empirical results from four experiments show that the approach does well at finding meaningful levels of hierarchical sequences. |
| Paper Nr: | 192 |
| Title: | Cell Formation Problem: An Multithreading Tabu Search for Setup Time Optimization for Limited Machine Magazines - A New Solution for a Classical Problem |
| Authors: | Arthur T. Gómez, Felipe R. Ferrary, José V. Canto Dos Santos and Leonardo Chiwiacowsky |
| Abstract: | This paper aims to present a solution for the Manufacturing Cell Formation Problem through the use of a multithreading Tabu Search that uses deterministic methods to effectively explore local optimum areas. Manufacturing Cell Formation problem involves the process of analysing parts and groups them according to their similarity. This paper aims maximize the production efficiency, by minimizing the machine setup time in a limited magazine size through the reduction of tool changes by creating clusters of parts that share machining tools and present an initial scheduling based on tool changes reduction. In order to valid the proposed algorithm, the results obtained are compared against other Tabu Search solutions proposed in the literature. |
| Paper Nr: | 208 |
| Title: | The Impact of the Diversity on Multiple Classifier System Performance - Identifying Changes in the Amount of Fuel in the Fleet Management System |
| Authors: | Rafał Łysiak and Marek Kurzyński |
| Abstract: | When it comes to the use of any recognition systems in the real world environment, it turns out that the reality differs from the theory. There is an assumption that the distribution of the incoming data will be at least similar to the distribution of the data, which were used during the learning process and that learning dataset represents the entire space of the problem. In fact, the incoming data differ from the training set and usually cover only a part of the feature space. Very often we have to deal with imbalanced datasets which leads to underfitting of classifiers in the final ensemble. In this paper we present the Multiple Classifier System based on Random Reference Classifier in the problem of fuel level change detection in the fleet management systems. The ensemble selection process uses probabilistic measures of competence and diversity at the same time. We compare different methods to determine the diversity within the ensemble. |
| Paper Nr: | 221 |
| Title: | Application of Artificial Neural Network State Feedback Controller to Torque Ripple Minimization of PMSM |
| Authors: | L. Niewiara, T. Tarczewski and L. M. Grzesiak |
| Abstract: | This paper deals with the problem of torque ripple minimization of permanent magnet synchronous motor. The novelty of the presented approach lays in precisely maintain the level of the voltage source inverter DC voltage demanded for proper operation of the motor. An additional voltage matching circuit with state feedback controller is introduced in order to control of the inverter DC voltage. In the proposed solution model of a plant (i.e. permanent magnet synchronous motor fed by voltage source inverter with additional voltage matching circuit) is non-linear and non-stationary. An adaptive state feedback controller is developed by using an artificial neural network, which approximates non-linear control gain surfaces. A simple adaptation algorithm based on 2 low-order low-pass filters is used. Simulation results illustrate the proposed approach in comparison to typical drive with voltage source inverter and stationary state feedback controller. |
| Paper Nr: | 270 |
| Title: | Particle Swarm Optimization Based Model Predictive Control for Constrained Nonlinear Systems |
| Authors: | Jean Thomas |
| Abstract: | Particle Swarm Optimization (PSO) is an effective optimization technique that can efficiently solve nonlinear and non-convex optimization problems, however, system constraints like output and states constraints cannot be considered. On the other hand, Model Predictive Control (MPC) is an efficient optimization technique that can offer the optimal solution while respecting the given constraints; however, for constrained nonlinear/non-convex optimization this turned out to be a complex problem and in many cases, it became inapplicable in real-time due to the computation burden. This paper presents a Particle Swarm Optimization based Model Predictive Control for constrained nonlinear systems. It is a simple control algorithm that offers a sub-optimal solution, in reasonable time, for nonlinear systems while respecting the given constraints. The proposed technique can consider both hard and soft constraints. The new developed technique is not considered as a computation burden, and on-line application is possible. An application of the proposed technique to a speed control of linear induction control is presented. |
| Paper Nr: | 274 |
| Title: | Numerical Investigation of Newton’s Method for Solving Continuous-time Algebraic Riccati Equations |
| Authors: | Vasile Sima and Peter Benner |
| Abstract: | Refined algorithms for solving continuous-time algebraic Riccati equations using Newton’s method with or without line search are discussed. Their main properties are briefly presented. Algorithmic details incorporated in the developed solver are described. The results of an extensive performance investigation on a large collection of examples are summarized. Several numerical difficulties and observed unexpected behavior are reported. These algorithms are strongly recommended for improving the solutions computed by other solvers. |
| Paper Nr: | 289 |
| Title: | The Dependence of Piezoresistivity of Elastomer/Nanostructured Carbon Composites on Dynamic Mechanical Load Frequency |
| Authors: | Artis Linarts, Imants Barons and Maris Knite |
| Abstract: | The aim of this article is to determine piezoresistive sensitivity of elastomer nanostructured carbon composites at dynamic loading tests and show the piezoresistive effect correlations to various frequencies of applied mechanical force in a manner that could provide a parameter of the highest detectible dynamic load frequency. This parameter is crucial when determining sensor’s usability in possible applications. There are only few articles on conductive polymer composite sensitivity in dynamic mechanical loading tests.With this article we are trying to estimate the values of dynamic loading frequencies in which sensor would be functional. |
Area 2 - Robotics and Automation
Full Papers| Paper Nr: | 8 |
| Title: | Preliminary Tests and Validation Protocols for an Artificial Multifunctional Foot |
| Authors: | João Almeida, Maria José Ferreira, Pedro Lobarinhas, Luís F. Silva, Abílio Leite, Alfredo Araújo and Fernando Sousa |
| Abstract: | This project consisted in the development of a multifunctional artificial foot with the ability to duplicate a human foot in a laboratory testing environment, with the purpose to evaluate and simulate footwear’s performance under certain conditions. This foot is used as a laboratory prototype and it is multi-segmented, meaning that each foot section is controlled independently in terms of heat generation and sweating rate. Therefore it is possible to simulate more accurately the real behaviour of a human foot. The device produces thermal insulation values that will help to design footwear with better performance in terms of thermal comfort perception, replacing human volunteers in thermal comfort tests, which are very subjective. The prototype was tested and validated following international standard proceedings, and the outcome results indicate that thermal insulation values are within the range of expected values obtained in other foot thermal manikins or in tests carried out with human volunteers. This fact suggests that this lab prototype can be used as a reference in future thermal comfort evaluations. |
| Paper Nr: | 17 |
| Title: | Model Predictive 2DOF PID Control for Slip Suppression of Electric Vehicles |
| Authors: | Tohru Kawabe |
| Abstract: | This paper propose the design method of 2DOF (two degrees of freedom) PID (Proportional-Integral- Derivative) controller based on MPC (Model predictive control). This controller is called as MP-2DOF PID controller. The method repeatedly optimizes the control parameters for each control period by solving an optimization problem based on the MPC algorithm, while using the 2DOF PID controller structure. Generally 2DOF PID controller can be implemented by a simple extension of the pre-existing PID controller with feed-forward element. This means we can get better performance without much cost. The proposed method aims to improve the maneuverability, the stability and the low energy consumption of EVs (Electric Vehicles) by controlling the wheel slip ratio. There also include numerical simulation results to demonstrate the effectiveness of the method. |
| Paper Nr: | 24 |
| Title: | Approximate Distance Queries for Path-planning in Massive Point Clouds |
| Authors: | David Eriksson and Evan Shellshear |
| Abstract: | In this paper, algorithms have been developed that are capable of efficiently pre-processing massive point clouds for the rapid computation of the shortest distance between a point cloud and other objects (e.g. triangulated, point-based, etc.). This is achieved by exploiting fast distance computations between specially structured subsets of a simplified point cloud and the other object. This approach works for massive point clouds even with a small amount of RAM and was able to speed up the computations, on average, by almost two orders of magnitude. Given only 8 GB of RAM, this resulted in shortest distance computations of 30 frames per second for a point cloud originally having 1 billion points. The findings and implementations will have a direct impact for the many companies that want to perform path-planning applications through massive point clouds since the algorithms are able to produce real-time distance computations on a standard PC. |
| Paper Nr: | 36 |
| Title: | Parallel Robotic Manipulation via Pneumatic Artificial Muscles |
| Authors: | Dimitris Gryparis, George Andrikopoulos and Stamatis Manesis |
| Abstract: | In this article, a 6 Degree-of-Freedom (DOF) parallel manipulator, actuated by Pneumatic Artificial Muscles (PAMs), is being presented. Incorporated in a two Stewart Platform-based design, the novel manipulator’s motion capabilities are being examined through kinematic analysis, while the open-loop operation characteristics and performance of the manipulator’s control via a multiple PID-based scheme are being experimentally evaluated. |
| Paper Nr: | 63 |
| Title: | Multi-cameras Visual Servoing to Perform a Coordinated Task using a Dual Arm Robot |
| Authors: | Renliw Fleurmond and Viviane Cadenat |
| Abstract: | This paper deals with the problem of coordinating a dual arm robot equipped with several cameras. Our goal is to propose a vision-based control strategy allowing to realize a real cooperation of the two arms. The idea is to sequence different vision based tasks built from visual features describing the relative pose between the cap and the pen. Simulation results validate our approach. |
| Paper Nr: | 95 |
| Title: | Task Level Optimal Control of a Simulated Ball Batting Robot |
| Authors: | Dennis Schüthe and Udo Frese |
| Abstract: | We developed a task-oriented controller based on optimal finite horizon control. We demonstrate this on a flexible ball playing robot with redundant degrees of freedom. The task is to reach a specified Cartesian position and velocity of the bat at a specified time, in order to rebound the ball. The controller must maintain high accuracy and react to disturbances and changing conditions. Therefore, we formulate this as an optimal control problem giving the controller the possibility to autonomously distribute motor torques amongst the redundant degrees of freedom. In simulations, we show the accuracy of the controller, the intelligent distribution of motor torques, as well as robustness against disturbances and adaptation to changing conditions. |
| Paper Nr: | 99 |
| Title: | A Navigational Framework Combining Visual Servoing and Spiral Obstacle Avoidance Techniques |
| Authors: | Marcus Futterlieb, Viviane Cadenat and Thierry Sentenac |
| Abstract: | This paper presents a navigational framework which enables a robot to perform Long Range Navigation in the context of the Air-Cobot-Project in which a robot is used to execute an autonomous pre-flight inspection on an aircraft. The robot is equipped with Laser range finders and a mobile stereo camera system. The idea is to guide the robot to the pre-defined checkpoints using a Visual Servoing controller based on video data, while avoiding static and moving obstacles. The contribution of the paper is an avoidance technique derived from the spiral flight path of insects applied to the Laser range data. Simulation results validate the whole approach. |
| Paper Nr: | 104 |
| Title: | Soil Strength-based Estimation of Optimal Control Parameters for Wheeled Robots on Rough Terrain |
| Authors: | Jayoung Kim and Jihong Lee |
| Abstract: | On rough terrain, there are a variety of soil types having different soil strength. It means that it is needed for outdoor robots to change wheel control strategies since optimal slip and maximum traction levels on wheels differ depending on soil strength. Therefore this paper proposes an algorithm for acquiring optimal control parameters, such as maximum traction coefficient and optimal slip ratio to maximize traction or minimize energy consumption, based on estimating strength of soils. In this paper the optimal models of wheel traction and slip are derived through indoor experiments by a testbed for analysis of wheel-terrain interactions on three types of soil; grass, gravel and sand. For estimating soil strength, actual traction coefficient, including information of motion resistance, is observed by a state estimator related to wheeled robot dynamics. The actual traction coefficient and slip ratio on wheels are employed to estimate soil strength by a numerical method on the basis of derived optimal models. The proposed algorithm was verified through real driving experiments of a wheeled robot on various types of soil. |
| Paper Nr: | 106 |
| Title: | A Pursuit-evasion Game Between Unmanned Aerial Vehicles |
| Authors: | Alexander Alexopoulos, Tobias Schmidt and Essameddin Badreddin |
| Abstract: | In this paper the problem of two-player pursuit-evasion games with unmanned aerial vehicles (UAVs) in a three-dimensional environment is solved. A game theoretic framework is presented, which enables the solution of dynamic games in discrete time based on dynamic programming. The UAV agents taking part in the pursuit-evasion game are two identical quad-rotors with the same non-linear state space model, while the evaders’ absolute velocity is smaller than the pursuers’. The convergence of the pursuit-evasion game is shown in numerical simulations. Finally, the approach is simulated on an embedded computer and tested for real-time applicability. Hence, the implementation and real-time execution on a physical UAV system is feasible. |
| Paper Nr: | 126 |
| Title: | Design of Safe Reactional Controller for Chamber Pressure in Climbing Robot CREA |
| Authors: | Atabak Nezhadfard, Steffen Schütz, Daniel Schmidt and Karsten Berns |
| Abstract: | CREA robot is designed to climb up concrete walls. The robot uses the suction mechanism to provide adhesion and wheel mechanism for locomotion. Eleven chambers which are connected to one common reservoir are responsible to produce adhesion force. A controller is developed to independently control each chamber while satisfying certain criteria on the safety of the robot. It is also designed to reach minimum friction between active inflatable seals and wall. In conclusion, the controller is able to successfully meet the conditions of stability, minimum friction and safety. |
| Paper Nr: | 153 |
| Title: | A Multi-layer Approach for Interactive Path Planning Control |
| Authors: | Simon Cailhol, Philippe Fillatreau, Jean-Yves Fourquet and Yingshen Zhao |
| Abstract: | This work considers path-planning processes for manipulation tasks such as assembly, maintenance or disassembly in a Virtual Reality (VR) context. The approach consists in providing a collaborative system associating a user immersed in VR and an automatic path planning process. It is based on semantic, topological and geometric representations of the environment and the planning process is split in two phases: coarse and fine planning. The automatic planner suggests a path to the user and guides him trough a haptic device. The user can escape from the proposed solution if he wants to explore a possible better way. In this case, the interactive system detects the user’s intention in real-time and computes a new path starting from the user’s guess. Experiments illustrate the different aspects of the approach: multi-representation of the environment, path planning process, user’s intent prediction and control sharing. |
| Paper Nr: | 154 |
| Title: | Stereo-based Pedestrian Detection in Crosswalks for Pedestrian Behavioural Modelling Assessment |
| Authors: | D. F. Llorca, I. Parra, R. Quintero, C. Fernández, R. Izquierdo and M. A. Sotelo |
| Abstract: | In this paper, a stereo- and infrastructure-based pedestrian detection system is presented to deal with infrastructure-based pedestrian safety measurements as well as to assess pedestrian behaviour modelling methods. Pedestrian detection is performed by region growing over temporal 3D density maps, which are obtained by means of stereo reconstruction and background modelling. 3D tracking allows to correlate the pedestrian position with the different pedestrian crossing regions (waiting and crossing areas). As an example of an infrastructure safety system, a blinking luminous traffic sign is switched on to warn the drivers about the presence of pedestrians in the waiting and the crossing regions. The detection system provides accurate results even for nighttime conditions: an overall detection rate of 97.43% with one false alarm per each 10 minutes. In addition, the proposed approach is validated for being used in pedestrian behaviour modelling, applying logistic regression to model the probability of a pedestrian to cross or wait. Some of the predictor variables are automatically obtained by using the pedestrian detection system. Other variables are still needed to be labelled using manual supervision. A sequential feature selection method showed that time-to-collision and pedestrian waiting time (both variables automatically collected) are the most significant parameters when predicting the pedestrian intent. An overall predictive accuracy of 93.10% is obtained, which clearly validates the proposed methodology. |
| Paper Nr: | 162 |
| Title: | Detection and Tracking of Dynamic Objects using 3D Laser Range Sensor on a Mobile Platform |
| Authors: | Josip Ćesić, Ivan Marković, Srećko Jurić-Kavelj and Ivan Petrović |
| Abstract: | In this paper we present an algorithm for detection, extraction and tracking of moving objects using a 3D laser range sensor. First, ground extraction is performed using random sample consensus for model parameter estimation. Afterwards, to downsample the point cloud, a voxel grid filtering is executed and octree data structure is used. This data structure enables an efficient detection of differences between two consecutive point clouds, based on which clustering of dynamic parts of the cloud is performed. The obtained clusters are then expanded over the set of static voxels in order to cover entire objects. In order to account for ego-motion an iterative closest point registration technique with an initial transformation guess obtained by odometry of the platform is used. As the final step, we present a tracking algorithm based on joint probabilistic data association (JPDA) filter with variable process and measurement noise taking into account velocity and position of the tracked objects. However, JPDA filter assumes a constant and known number of objects in the scene, and therefore we use track management based on entropy. Experiments are performed using a setup consisting of a Velodyne HDL-32E mounted on top of a mobile platform in order to verify the developed algorithms. |
| Paper Nr: | 163 |
| Title: | Control of a Pedaled, Self-balanced Unicycle with Adaptation Capability |
| Authors: | Chun-Feng Huang and T.-J. Yeh |
| Abstract: | In this paper, a pedaled, self-balanced, personal mobility vehicle is developed. The vehicle is structurally similar to a pedaled unicycle but uses a brushless DC (BLDC) hub motor as its main driving wheel. In order to reduce the interference and provide a better human-machine interaction, a novel balancing controller with adaptation capability is proposed. This balancing controller, when working together with a specially designed low-level BLDC driver, can adapt to the uncertain center of gravity of the vehicle frame plus the rider, and the amount of motor torque that fights against the pedaling torque can be reduced to minimum. The performance of the control system is validated by simulations. |
| Paper Nr: | 165 |
| Title: | Development of Gait Measurement Robot for Prevention of Falls in the Elderly |
| Authors: | Ayanori Yorozu, Mayumi Ozawa and Masaki Takahashi |
| Abstract: | To prevent falls in the elderly, gait measurements such as several-meters walking test and gait trainings are carried out in community health activities. To evaluate the risk of falling of the participant, it is necessary to measure foot contact times and positions so that the stride length of each leg and the walking speed can be used as evaluation parameters. However, the conventional measurement systems are difficult to install for use in community health activities because of their scale, cost and constraints of the measurement range. In this study, we propose a novel gait measurement system which uses an autonomous mobile robot with laser range sensor (LRS) for a long-distance walking test in a real living space regardless of detection range of sensor. The robot sequentially estimates its own pose and acquires the position of both legs of the participant. The robot leads the participant from the start to the goal of the walking test while maintaining a certain distance from the participant. Then, the foot contact times and the positions are calculated by analyzing estimated position and speed of each leg. From the experimental results, it was confirmed that the proposed robot could acquire the foot contact times and positions. |
| Paper Nr: | 167 |
| Title: | A Comparison of General-Purpose FOSS Compression Techniques for Efficient Communication in Cooperative Multi-Robot Tasks |
| Authors: | Gonçalo S. Martins, David Portugal and Rui P. Rocha |
| Abstract: | The efficient sharing of information is a commonly overlooked problem in methods proposed for cooperative multi-robot tasks. However, in multi-robot scenarios, especially when the communication network’s quality of service is less than desirable, either in bandwidth or reliability, efficient information exchange is a key aspect for the successful deployment of coordinated robotic teams with proper exchange of information. Compression is a popular, well-studied solution for transmitting data through constrained communications channels, and many general-purpose solutions are available as free and open-source software (FOSS) projects. There are various benchmarking tools capable of comparing the performance of these techniques, but none that differentiate between them in the compression of the typical data exchanged among robots in a cooperative task. Thus, choosing a compression technique to be used in this context is still a challenge. In this paper, the issue of efficiently communicating data among robots is addressed by comparing the performance of various compression techniques in a case study of multi-robot simultaneous localization and mapping (SLAM) scenarios using occupancy grids, a cooperative task usually requiring the exchange of large amounts of data. |
| Paper Nr: | 178 |
| Title: | A Time-analysis of the Spatial Power Spectra Indicates the Proximity and Complexity of the Surrounding Environment |
| Authors: | Ana Carolina Quintela Alves Vilares da Silva and Cristina Santos |
| Abstract: | In this paper, the statistical properties of both simulated and real image sequences, are examined. The image sequences used depict different types of movement, including approaching, receding, translation and rotation. A time analysis was performed to the spatial power spectra obtained for each frame of the image sequences used. Here it is discussed how this information is correlated to the proximity of the objects in the visual scene, as well as with the complexity of the environment. Results show how scene and visual categorization based directly on low-level features, without segmentation or object recognition stages, can benefit object localization and proximity. The work here proposed is even more interesting considering its simplicity, which could be easily applied in a robotic platform responsible for exploratory missions. |
| Paper Nr: | 179 |
| Title: | Using Ultracapacitors as Energy-storing Devices on a Mobile Robot Platform Power System for Ultra-fast Charging |
| Authors: | Carlos Arantes, João Sepúlveda, João Sena Esteves, Hugo Costa and Filomena Soares |
| Abstract: | The large charging times required by conventional batteries constitute an important limitation in many applications. The use of ultracapacitors as energy storage elements allows substantially faster charging. This paper presents a power supply system developed in order to validate the possibility of providing a mobile robot platform with an electrical energy storage system based on ultracapacitors and batteries, ensuring both the autonomy and the charging time required by this vehicle. Both simulations results and experimental results – also presented in this paper – validate this possibility. Using exclusively one ultracapacitors module as energy-storing device of the new power supply system, the mobile platform achieved an autonomy of 22 minutes after a charging time of 1 minute and 57 seconds. The charging time is less than 10% of the autonomy time. The system also proved its ability to properly charge lead-acid batteries or nickel–metal hydride batteries, which may be used as energy-storing devices, allowing the mobile platform to achieve greater autonomy than the one obtained with ultracapacitors (at the cost of larger charging times). |
| Paper Nr: | 188 |
| Title: | Embodied Localization in Visually-guided Walk of Humanoid Robots |
| Authors: | Hendry Ferreira Chame and Christine Chevallereau |
| Abstract: | Humanoid robots are conceived to resemble the body and comportment of the human beings. Among the behavior repertoire, the possibility of executing visually-guided tasks is crucial for individual adaptation and relies on the on-board sensory system. However, the research on walk and localization is far from conclusive. Given the difficulties in the processing of the visual feedback, some studies have treated the problem by placing external sensors on the environment; thus neglecting the corporal metaphor. Others, despite exploring on-board solutions; have relied on an extensive model of the environment, thus considering the system as an information processing unit, abstracted from a body. This work presents a methodology to achieve embodied localization to serve visually-guided walk. The solution leans on robust segmentation from monocular vision, ego-cylindrical localization, and minimal knowledge about stimuli in the environment. |
| Paper Nr: | 190 |
| Title: | Enhanced Physical Interaction Performance for Compliant Joint Manipulators using Proxy-based Sliding Mode Control |
| Authors: | Navvab Kashiri, Nikos G. Tsagarakis, Michael Van Damme, Bram Vanderborght and Darwin G. Caldwell |
| Abstract: | The use of typical position controllers for robots working around humans can involve some risks when unintended physical human-robot interactions occur. In order to benefit from a proper tracking performance during normal operations, and a smooth and damped recovery from position errors due to contacts with external objects/agents, Proxy-based Sliding Mode Control was proposed. While the efficacy of this controller in fully actuated manipulators was discussed, the employment of this controller in underactuated systems has not been studied so far. This paper introduces a control scheme to implement this controller in a class of underactuated systems. Specifically, the control of flexible joint manipulators possessing passive elastic elements in series with motors is studied. The formulation of Proxy-based Sliding Mode Control is adopted according to the stability requirements of this type of dynamic systems, and a torque controller required for the regulation of the the output torque of actuation units is designed using the Feedback Linearization and the Linear Quadratic optimal control approach. The performance of the proposed scheme is demonstrated in dynamic simulation of an anthropomorphic compliant arm. |
| Paper Nr: | 224 |
| Title: | Resorting Vehicles in an Automotive Manufacturing Environment |
| Authors: | Jens Feller, Bernhard Mauersberg, Wolfgang Mergenthaler, Yvonne Feller and Lutz Müller |
| Abstract: | One of the most important concepts in an automotive production process is that of a manufacturing sequence. Sequencing has a vital influence on a series of important performance indicators such as load balance, setup time, setup cost, timeliness, flow of material etc. Generating appropriate sequences has thus become a key task for the automotive production planner. Ensuring the stability of a sequence, once it has been determined, by sorting its actual version back into the form intended originally, however, with systematic means, is a new issue gaining recently more importance. This problem represents the main topic of the present paper. Instruments for physically resorting vehicles are sorting channels and parking spaces. Both instruments are closely related to one another, as will be shown. |
| Paper Nr: | 235 |
| Title: | Complete Stiffness Model for a Serial Robot |
| Authors: | Alexandr Klimchik, Stephane Caro, Benoit Furet and Anatol Pashkevich |
| Abstract: | The paper addresses a problem of robotic manipulator calibration. The main contributions are in the area of the elastostatic parameters identification. In contrast to other works, the considered approach takes into account elastic properties of both links and joint. Particular attention is paid to generation of the complete and irreducible stiffness model that is suitable for the identification. To solve the problem, physical and algebraic model reduction methods are proposed. They are based on taking into account the physical properties of the manipulator elements and structure of the corresponding observation matrix. The advantages of the developed approach are illustrated by an application example that deals with elastostatic calibration of an industrial robot. |
| Paper Nr: | 250 |
| Title: | An Improved Real-time Method for Counting People in Crowded Scenes Based on a Statistical Approach |
| Authors: | Shirine Riachi, Walid Karam and Hanna Greige |
| Abstract: | In this paper, we present a real-time method for counting people in crowded conditions using an indirect/statistical approach. Our method is based on an algorithm by Albiol et al. that won the PETS 2009 contest on people counting. We employ a scale-invariant interest point detector from the state of the art coined SURF (Speeded-Up Robust Features), and we exploit motion information to retain only interest points belonging to moving people. Direct proportionality is then assumed between the number of remaining SURF points and the number of people. Our technique was first tested on three video sequences from the PETS dataset. Results showed an improvement over Albiol’s in all the three cases. It was then tested on our set of video sequences taken under various conditions. Despite the complexity of the scenes, results were very reasonable with a mean relative error ranging from 9.36% to 17.06% and a mean absolute error ranging from 1.13 to 3.33. Testing this method on a new dataset proved its speed and accuracy under many shooting scenarios, especially in crowded conditions where the averaging process reduces the variations in the number of detected SURF points per person. |
| Paper Nr: | 266 |
| Title: | Optimal Walking of an Underactuated Planar Biped with Segmented Torso |
| Authors: | Zhongkai Chen, Nafissa El Yaaqoubi and Gabriel Abba |
| Abstract: | Recently, underactuated bipeds with pointed feet have been studied to achieve dynamic and energy efficient robot walking patterns. However, these studies usually simplify a robot torso as one link, which is different from a human torsos containing 33 vertebrae. In this paper, therefore, we study the optimal walking of a 6-link planar biped with a segmented torso derived from its 5-link counterpart while ensuring that two models are equivalent when the additional torso joint is locked. For the walking, we suppose that each step is composed of a single support phase and an instantaneous double support phase, and two phases are connected by a plastic impact mapping. In addition, the controlled outputs named symmetry outputs capable of generating exponentially stable orbits using hybrid zero dynamics, are adopted to improve physical interpretation. The desired outputs are parameterized by Bézier functions, with 5-link robot having 16 parameters to optimize and 6-link robot having 19 parameters. According to our energy criterion, the segmented torso structure may reduce energy consumption up to 8% in bipedal walking, and the maximum energy saving is achieved at high walking speeds, while leaving the criteria at low walking speeds remain similar for both robots. |
Short Papers
| Paper Nr: | 9 |
| Title: | Fluid Mechanics for Path Planning and Obstacle Avoidance of Mobile Robots |
| Authors: | Rainer Palm and Dimiter Driankov |
| Abstract: | Obstacle avoidance is an important issue for off-line path planning and on-line reaction to unforeseen appearance of obstacles during motion of a non-holonomic mobile robot along a predefined trajectory. Possible trajectories for obstacle avoidance are modeled by the velocity potential using a uniform flow plus a doublet representing a cylindrical obstacle. In the case of an appearance of an obstacle in the sensor cone of the robot a set of streamlines is computed from which a streamline is selected that guarantees a smooth transition from/to the planned trajectory. To avoid collisions with other robots a combination of velocity potential and force potential and/or the change of streamlines during operation (lane hopping) are discussed. |
| Paper Nr: | 19 |
| Title: | High-Order Analytical Solution of Relative Motion Equation for Satellite Formation Flying in Elliptical Orbit |
| Authors: | Ting Wang, Hanlun Lei, Bo Xu, Tian Guan and Jun Guo |
| Abstract: | The paper studied relative motion equation for satellite formation flying with large separations. The configuration is traditionally designed by the periodic solutions of the C-W equation in circle reference orbit or Lawden equation in elliptic reference orbit. Hence, the linear solutions are more suitable for the configuration with small scale formation than large scale formation. However, in some specific situations, it is necessary to use satellites with large separations. Then the paper studied relative motion based on the nonlinear equations in an elliptic reference orbit. The solution is expanded as series form with respect to the eccentricity of the reference orbit, in-plane amplitude and out-of-plane amplitude. Taking the Lawden periodic solution as starting point, the high-order analytical solution is constructed by Lindstedt-Poincare method. Particularly, as the eccentricity is zero, the analytical solution degenerated to express the relative motion in circle reference orbit. Finally, the practical convergence of the analytical solution is discussed in order to examine its validity and applicability. |
| Paper Nr: | 42 |
| Title: | Decentralized Supervisory Control of Discrete Event Systems - Moving Decisions Closer to Actions |
| Authors: | Ahmed Khoumsi and Hicham Chakib |
| Abstract: | In decentralized control of discrete event systems, two main agents contribute to the computation of decisions: local supervisors and fusion modules. The local supervisors process the information detected on the plant and its environment, and transmit their results to the fusion modules. The latter process what is received from the local supervisors in order to decide actions to be applied to the plant. In the existing decentralized control architectures, the local supervisors execute complex operations, while the fusion modules execute simple operations. In the present article, we propose to move the decision computation complexity from local supervisors to fusion modules, that is what we term: moving decisions closer to actions. We justify this movement of decision and develop a simple architecture based on it. With the proposed architecture, the local supervisors are simple local observers, while all decisions are computed by the fusion modules. We characterize the class of languages achievable with the new architecture and compare it with the classes of languages achievable with the existing decentralized architectures and the centralized architecture. |
| Paper Nr: | 46 |
| Title: | Optimizing Camera Placement in Motion Tracking Systems |
| Authors: | Dávid Szalóki, Kristóf Csorba and Gábor Tevesz |
| Abstract: | This paper discusses the placement of cameras in order to achieve the highest possible localization accuracy. It is reached by using several cameras with redundant fields of views. A camera model is introduced and the components which cause the localization errors are identified. The localization accuracy measure is defined for one and for multiple cameras too. The problem of adding a new camera to the system in order to improve the accuracy is formulated. The method for finding the optimal placement of this new camera is presented. Some features are enumerated which can be applied for getting an advanced method. |
| Paper Nr: | 58 |
| Title: | Depth Sensor Placement for Human Robot Cooperation |
| Authors: | Max Stähr, Andrew M. Wallace and Neil M. Robertson |
| Abstract: | Continuous sensing of the environment from a mobile robot perspective can prevent harmful collisions between human and mobile service robots. However, the overall collision avoidance performance depends strongly on the optimal placement of multiple depth sensors on the mobile robot and maintains flexibility of the working area. In this paper, we present a novel approach to optimal sensor placement based on the visibility of the human in the robot environment combined with a quantified risk of collision. Human visibility is determined by ray tracing from all possible camera positions on the robot surface, quantifying safety based on the speed and direction of the robot throughout a pre-determined task. A cost function based on discrete cells is formulated and solved numerically for two scenarios of increasing complexity, using a CUDA implementation to reduce computation time. |
| Paper Nr: | 79 |
| Title: | Information Framework for Energy Systems Using Agent-based Cloud Computing Technology |
| Authors: | Francisco Maturana, Luois Mann, Juan Asenjo, Shweta Chatrola and Ray Staron |
| Abstract: | We present a novel idea to combine agent technology and cloud computing for monitoring an energy system. We describe how a cloud infrastructure can be useful in storing and processing near real-time sensor data. This paper also presents the implementation of the cloud computing capability as Software-as-a-Service (SaaS) and reporting capabilities in cloud throughout a network of worker role and procedural assemblies. This system generates alarms based on various conditions emerging from the sensor data of an energy generation system. |
| Paper Nr: | 96 |
| Title: | Operational Assistance System using 3-DOF Joystick with Reaction Force Display to Load Transfer Machine in a Plane |
| Authors: | Tomoya Kuneguchi, Yoshiyuki Noda, Yukinori Sago and Kiyoaki Kakihara |
| Abstract: | This paper is concerned with an operational assistance system to a load transfer machine in a plane such as a manually guided vehicle and a crane without vertical transfer. In the transfer machine, collisions with obstacles are often occurred by the incorrect operations. Therefore, in order to avoid the obstacles to the transfer machine, the operational assistance system using 3-DOF(3 Degree of Freedom) joystick with reaction force display is proposed in this study. The 3-DOF joystick enables operator to manipulate the transfer machine with back-and-forth, left-and-right, and rotation motions. And, it has motors for presenting the reaction force on each axis. In this system, the joystick displays the reaction force which consists of the virtual elastic force and viscosity resistance, which are controlled by PD control gains. By associating the gains in the PD control with the distance between the obstacles and the transfer object, the joystick operation is constrained for avoiding the obstacles. The effectiveness of the proposed operational assistance system is verified by the experiments using the simulator of the transfer machine manipulated by the 3-DOF joystick. |
| Paper Nr: | 97 |
| Title: | Comparison of Different Powered-wheelchair Control Modes for Individuals with Severe Motor Impairments |
| Authors: | Alfredo Chávez, Héctor Caltenco and Vítězslav Beran |
| Abstract: | This paper presents the preliminary evaluation of different powered-wheelchair control modes for individuals with severe motor impediments. To this end, a C400 Permobil wheelchair has been updated with a control command communication interface and equipped with a scanning laser sensor to carry out the automation algorithms that are part of the robot operating system framework. A pilot test was performed with three different modalities; hand-joystick mode, tongue-joystick mode and autonomous mode. The results of the tests have proven the feasibility of using a power wheelchair either autonomously or controlled by users interchangeably in order to continue the development towards a better user/wheelchair shared-control paradigm. |
| Paper Nr: | 109 |
| Title: | A Real-time Motion Data Reduction and Restoration Compatible with Robot’s Physical Limits |
| Authors: | Doik Kim, Jung-Min Park and Seokmin Hong |
| Abstract: | In order to control a robot, motion data obtained from various interface devices such as haptic and tele-operating interfaces, and a motion capture system, or from predefined parametric equations are needed. It is hard to store and transmit the data because of their high control frequency and synchronization problem. In addition, usually, all these data are only for one target robot system, i.e., it is hard to use them to other robot system with different hardware limits. In order to solve the problems, the reduction of the original data is conducted with two stage magnitude quantization and the restoration without violating the hardware limits, such as maximum velocity, acceleration, etc., is conducted with the convolution interpolation, in this paper. The proposed method can be used in on-line data transmission and for off-line data storage. |
| Paper Nr: | 114 |
| Title: | Robotic Grasping and Manipulation Controller Framework - Architecture Redevelopment |
| Authors: | Pavel Dzitac, Abdul Md Mazid, Guy Littlefair and Ashwin Polishetty |
| Abstract: | This paper details the further improvements obtained by redesigning a previously offered Manipulation Controller Framework to provide support to an innovative, friction-based object slippage detection strategy employed by the robotic object manipulator. This upgraded Manipulation Controller Framework includes improved slippage detection functionality and a streamlined architecture designed to improve controller robustness, reliability and speed. Improvements include enhancements to object slippage detection strategy, the removal of the decision making module and integration of its functionality into the Motion Planner, and the stream-lining of the Motion Planner to improve its effectiveness. It is anticipated that this work will be useful to researchers developing integrated robot controller architectures and slippage control. |
| Paper Nr: | 118 |
| Title: | Multiple Camera Human Detection and Tracking inside a Robotic Cell - An Approach based on Image War, Computer Vision, K-d Trees and Particle Filtering |
| Authors: | Matteo Ragaglia, Luca Bascetta and Paolo Rocco |
| Abstract: | In an industiral scenario the capability to detect and track human workers entering a robotic cell represents a fundamental requirement to enable safe and efficient human-robot cooperation. This paper proposes a new approach to the problem of Human Detection and Tracking based on low-cost commercial RGB surveillance cameras, image warping techniques, computer vision algorithms, efficient data structures such as kdimensional trees and particle filtering. Results of several validation experiments are presented. |
| Paper Nr: | 124 |
| Title: | Development of the Autonomous Mobile Overhead Traveling Crane in Consideration of On-line Obstacle Recognition, Path Planning and Oscillating Control |
| Authors: | Y. Kawasaki, A. Kaneshige and S. Ueki |
| Abstract: | In order to establish an autonomous overhead traveling crane system, it is needs to be constructed the obstacle recognition system, the path planning system and the control system of suppression of object swing automatically. These systems development is studied by our research group. In particular, the on-line obstacle recognition system using an ultrasonic sensor and the on-line obstacle avoidance path planning system of the on-line which extended the obstacle avoidance path planning method of the autonomous mobile robot which Srinivas has proposed to the three-dimensional obstacle avoidance path planning system are developed. Furthermore, the feed-forward control system using a notch filter is constructed. However, the feed-forward control system was not able to control object swing which occurred during initial deviation or transportation. Therefore, in order to improve the vibration suppression of object swing, 2-degrees of freedom control system is constructed in this research. It is unified with the obstacle recognition system and path planning system which are proposed until now, and the usefulness of the autonomous overhead traveling crane system integrated was confirmed. |
| Paper Nr: | 125 |
| Title: | Remote Handling Crane System for Use in Small Argon Compartment Hot-cell |
| Authors: | Jong Kwang Lee, Byung Suk Park, Seung-Nam Yu, Kiho Kim, Jonghui Han and Il-Je Cho |
| Abstract: | In this paper, we describe the design of a novel crane system for use in a small argon hot-cell where only a mechanical master-slave manipulator (MSM) within the limitation is available for the maintenance of the crane. To get a practically achievable solution for the design problem, we devised a remote actuation mechanism in which the electrical parts of the crane are separated from the mechanical parts and installed inside the workspace of the MSM for remote maintenance. Even though the design concept does not provide a thoroughly sufficient solution because the mechanical parts are placed out of the MSM’s workspace, the durability of the mechanical parts can be easily increased if they have a high safety margin. Therefore, the concept may be one of best solutions for our special crane system. In addition, we developed a servo-control system based on absolute positioning technology; therefore, it is possible for us to perform the given tasks more safely through an automatic operation. |
| Paper Nr: | 128 |
| Title: | The Effective Radius and Resistance to Slippage |
| Authors: | Pavel Dzitac, Abdul Md Mazid, Guy Littlefair and Ashwin Polishetty |
| Abstract: | This work reveals that parallel gripper flat-jaw configuration affects grasping effectiveness. An important finding is the fact that object grasp reliability is influenced significantly by gripper’s ability to develop high resistance to object rotation in the gripper. The concept of effective torque radius, which increases resistance to object rotation in the gripper, is presented here and can be extrapolated to other grasping devices and grasping strategies to improve their reliability and make them more effective. Grippers with full-jaw contact surface and those with discrete contact areas have been investigated using simple experimental setups. Essential mathematical models needed for analytical investigation, based on simple mechanics for full-jaw contact surfaces and discrete-jaw contact surfaces, are presented. These may be useful for gripper jaw design purposes. |
| Paper Nr: | 152 |
| Title: | Seam Tracking Control of Welding Robotic Manipulators Based on Adaptive Chattering-free Sliding-mode Control Technology |
| Authors: | Youmin Hu, Jie Liu, Bo Wu and Ming-Feng Ge |
| Abstract: | A novel adaptive sliding mode control (ASMC) algorithm is derived to deal with seam tracking control problem of welding robotic manipulator, during the process of large-scale structure component welding. The controllers robustness is verified by the Lyapunov stability theory, and the analytical results show that the proposed algorithm enables better high-precision tracking performance with chattering-free than classic sliding mode control (SMC) algorithm. |
| Paper Nr: | 157 |
| Title: | Characterization of Repeatability of XY-Theta Platform Held by Robotic Manipulator Arms using a Camera |
| Authors: | Anas Hijazi, Dimitri Lefebvre and Jean-François Brethe |
| Abstract: | This paper presents a XY-Theta micrometric platform, which is extremely compact and offers a wide 300 x 300 mm workspace. This platform is held by a serial kinematic chain of four revolute joints, constituting a redundant robot. Each point of the horizontal platform can be positioned under a vertical axis in a two-step approach: in a coarse positioning mode, the four axes are controlled to position and orientate the object with a position error less than 7 μm; in a fine mode, two axes are mechanically blocked while two others are controlled to reduce the final position error below 2 μm. The choice of the blocked and moving axes depends on the lever arm length and the mechanism is designed to optimize the link lengths to reduce the final position error. The aim of the paper is to characterize the platform repeatability performances. An estimation of the repeatability is performed with a camera. These results are then compared to previous results based on the stationary cube method. The two measurements methods lead to similar results with a repeatability close to 2 μm showing a significant improvement of the performances. |
| Paper Nr: | 166 |
| Title: | Rapidly Exploring Random Trees-based Initialization of MPC Technique Designed for Formations of MAVs |
| Authors: | Zdeněk Kasl, Martin Saska and Libor Přeučil |
| Abstract: | Motion planning techniques suited for initialization of Model Predictive Control based methodology applied for complex maneuvering and stabilization of formations of Micro Aerial Vehicles are proposed in this paper. Two approaches to initialization of the formation driving method will be described, experimentally verified, evaluated and compared. The first proposed method is based on multiobjective optimization of the trajectory guess obtained by a Rapidly Exploring Random Trees technique. It represents an easy to implement and robust method suited for off-line initialization of the formation driving algorithm. The second proposed method is based on sequential processing of parts of the obtained trajectory. This method is well scalable and thus applicable in large workspaces with complex obstacles. In addition, the second method enables a significant reduction of computational time as is shown by comparison of series of simulations in different environments. |
| Paper Nr: | 170 |
| Title: | Impedance Shaping Controller for Robotic Applications in Interaction with Compliant Environments |
| Authors: | Loris Roveda, Federico Vicentini, Nicola Pedrocchi, Francesco Braghin and Lorenzo Molinari Tosatti |
| Abstract: | The impedance shaping control is presented in this paper, providing an extension of standard impedance controller. The method has been conceived to avoid force overshoots in applications where there is the need to track a force reference. Force tracking performance are obtained tuning on-line both the position set-point and the stiffness and damping parameters, based on the force error and on the estimated stiffness of the interacting environment (an Extended Kalman Filter is used). The stability of the presented strategy has been studied through Lyapunov. To validate the performance of the control an assembly task is taken into account, considering the geometrical and mechanical properties of the environment (partially) unknown. Results are compared with constant stiffness and damping impedance controllers, which show force overshoots and instabilities. |
| Paper Nr: | 173 |
| Title: | Multispectral Data Fusion for Robotic Reconnaissance and Mapping |
| Authors: | Petra Kocmanova, Ludek Zalud, Frantisek Burian and Tomas Jilek |
| Abstract: | The aim of the paper is to describe the data-fusion from optical sensors for mobile robotics reconnaissance and mapping. Data are acquired by stereo pair of CCD cameras, stereo pair of thermal imagers, and TOF (time-of-flight) camera. The fusion is realized by means of spatial data from a TOF camera to ensure "natural" representation of a robot’s environment; thus, the thermal and CCD camera data are comprised in one stereo image presented to a binocular, head-mounted display. The data acquisition is performed using a sensor head, which is placed on an Orpheus-X3 robot; both the head and the robot were developed by our working group. After the geometrical calibration of each sensor, the positions of the sensors in 6DOFs are computed. The corresponding data from the CCD camera and the thermal imager are subsequently determined via homogeneous and perspective transformations. The result consists in an image containing aligned data from the CCD camera and the thermal imager for each eye. TOF camera calibration and its impact to the precision of fusion is described. Although the fusion is used for two different tasks – automatic environment mapping and visual telepresence, the utilised calibration and fusion algorithms are, in principle, the same. |
| Paper Nr: | 174 |
| Title: | Real-time People Detection and Mapping System for a Mobile Robot using a RGB-D Sensor |
| Authors: | Francisco F. Sales, David Portugal and Rui P. Rocha |
| Abstract: | In this paper, we present a robotic system capable of mapping indoor, cluttered environments and, simultaneously, detecting people and localizing them with respect to the map, in real-time, using solely a Red-Green-Blue and Depth (RGB-D) sensor, the Microsoft Kinect, mounted on top of a mobile robotic platform running Robot Operating System (ROS). The system projects depth measures in a plane for mapping purposes, using a grid-based Simultaneous Localization and Mapping (SLAM) approach, and pre-processes the sensor’s point cloud to lower the computational load of people detection, which is performed using a classical technique based on Histogram of Oriented Gradients (HOG) features, and a linear Support Vector Machine (SVM) classifier. Results show the effectiveness of the approach and the potential to use the Kinect in real world scenarios. |
| Paper Nr: | 175 |
| Title: | Robot Dynamic Model Identification Through Excitation Trajectories Minimizing the Correlation Influence among Essential Parameters |
| Authors: | Enrico Villagrossi, Giovanni Legnani, Nicola Pedrocchi, Federico Vicentini, Lorenzo Molinari Tosatti, Fabio Abbà and Aldo Bottero |
| Abstract: | Robot dynamics is commonly modeled as a linear function of the robot kinematic state from a set of dynamic parameters into motor torques. Base parameters (i.e. the set of theoretically demonstrated linearly-independent parameters) can be reduced to a subset of "essential" parameters by eliminating those that are negligible with respect to their contribution in motor torques. However, generic trajectories, if not properly defined, couple the contribution of such essential parameters into the motor torques, actually reducing the estimation accuracy of the dynamics parameters. The work presented here introduces an index for evaluating correlation influence among essential parameters along an executed trajectory. Such index is then exploited for an optimal search of excitatory patterns consistent with the kinematical coupling constraints. The method is experimentally compared with the results achievable by one of the most popular IRs dynamic calibration method. |
| Paper Nr: | 202 |
| Title: | Hybrid and Multi-controller Architecture for Autonomous System - Application to the Navigation of a Mobile Robot |
| Authors: | Amani Azzabi, Marwa Regaieg, Lounis Adouane and Othman Nasri |
| Abstract: | This paper deals with the problem of unicycle mobile robot navigation in cluttered environments. It presents in particular an approach which permits to verify the stability of the control architecture of mobile robot using the reachability analysis. To perform this analysis, we consider the robot as a hybrid dynamic system. The latter is modeled by an hybrid automata in order to verify the reachability property by using the interval analysis. The simulation results validate the proposed control architecture. |
| Paper Nr: | 203 |
| Title: | An Improvement in the Observation Model for Monte Carlo Localization |
| Authors: | Anas W. Alhashimi, Roland Hostettler and Thomas Gustafsson |
| Abstract: | Accurate and robust mobile robot localization is very important in many robot applications. Monte Carlo localization (MCL) is one of the robust probabilistic solutions to robot localization problems. The sensor model used in MCL directly influence the accuracy and robustness of the pose estimation process. The classical beam models assumes independent noise in each individual measurement beam at the same scan. In practice, the noise in adjacent beams maybe largely correlated. This will result in peaks in the likelihood measurement function. These peaks leads to incorrect particles distribution in the MCL. In this research, an adaptive sub-sampling of the measurements is proposed to reduce the peaks in the likelihood function. The sampling is based on the complete scan analysis. The specified measurement is accepted or not based on the relative distance to other points in the 2D point cloud. The proposed technique has been implemented in ROS and stage simulator. The result shows that selecting suitable value of distance between accepted scans can improve the localization error and reduce the required computations effectively. |
| Paper Nr: | 212 |
| Title: | Hybrid Control Architecture for Mobile Robots Navigation in Partially Known Environments |
| Authors: | Madjid Hank and Moussa Haddad |
| Abstract: | In this paper, we are interested on the development of hybrid control architecture for autonomous mobile robots navigation. The proposed approach consists of an architecture adapted for partially known environments. It includes both reactive navigation methods based on the principle of Sense & Act and deliberative methods based on the principle of Sense-Plan & Act. The used reactive navigation method is a behavioural approach for navigation in unknown environments. Whereas deliberative approach is based on a polynomial method called Random-Profile-Approach (RPA) for optimal trajectory planning in known environments. Controllers used for both trajectories tracking and reactive navigation are fuzzy inference systems. Simulation and experimental results to validate the proposed navigation strategy are presented. |
| Paper Nr: | 218 |
| Title: | Laser-based Tracking of People and Vehicles by Multiple Mobile Robots |
| Authors: | Masafumi Hashimoto, Ryunosuke Izumi, Yuto Tamura and Kazuhiko Takahashi |
| Abstract: | This paper presents laser-based tracking of moving objects conducted by a group of mobile robots located near one another. Each robot finds moving objects such as people, cars, and bicycles in its own laser-scanned images using a binarized occupancy-grid-based method. It then sends laser measurements related to the detected moving objects to a central server. The central server estimates the pose and size of the moving objects via the Kalman filter based on received measurements; it then feeds that information back to the robots. Rule-based and global-nearest-neighbor-based data associations are applied for matching of tracked objects and laser measurements in multitarget environments. In this cooperative tracking method, the central server collects the laser measurements from all robots; hence, the robots can always track invisible or partially invisible objects. The experimental results for two robots in an outdoor environment validate our tracking method. |
| Paper Nr: | 219 |
| Title: | The Influence of Bat Wings For Producing Efficient Net Body Forces in Bio-inspired Flapping Robots |
| Authors: | Julian Colorado, Claudio Rossi, Antonio Barrientos and Diego Patino |
| Abstract: | Bat wings contain dozens of joints that enable the animal to perform aggressive maneuvers by means of changing the wing shape during flight. There is evidence that the inertial forces produced by their wings during flapping have a key role in the attitude movements of the animal, i.e. aerial rotations. In fact, bats efficiently generate net body forces to manoeuvre by taking advantage of their large wing-to-body mass ratio. In this paper, the following question is formulated: Could a Micro Aerial Vehicle (MAV) inspired by the biomechanics of bats take advantage of the morphing-wings aimed at increasing net body forces? Using BaTboT, a novel bat-like MAV with highly articulated wings actuated by shape memory alloy actuators, our goal is to quantify the effects of different wing modulation patterns on the generation of net body forces. Experiments are carried out to confirm the important physical role that changing the wing shape enables: the contraction time of the wings (upstroke) should be faster than the extension time (downstroke), taking about 37.5% of the wingbeat period. This modulation pattern has enabled a lift force increment of 22% (from L = 0:92N to L = 1:12N), abrupt drag reduction (from D = 0:22N to D = 0:11N) and also an increase of net body forces (Fnet ) about 28% compared to those wing modulation patterns defined with equal periods for contraction/extension. These findings can be useful for accurate dynamics modelling and efficient design of flight controllers applied to morphing-wing micro aerial vehicles. |
| Paper Nr: | 234 |
| Title: | Design of a Multi-robot Bin Packing System in an Automatic Warehouse |
| Authors: | S. J. You and S. H. Ji |
| Abstract: | It is possible to reconfigure supply chains with less cost and time if we use the mobile-robot bin packing system. So, many companies attempt at adopting mobile robots as their new carrier in their own warehouse. However, it is difficult to utilize indoor service robots as a carrier due to the localization problem, the safety problem, and the narrow bin packing environment. So we propose a practically applicable solution technique for a multi-robot bin packing system in an automatic warehouse, which assures a reasonable safety, computation time and a real world application for more than 3 multi-robots. First, design criteria for out bin packing system are introduced. Second, we suggest some sketch of robot mechanical parts. Finally, the method of managing multi-robots in an automatic warehouse robot design with a collision motion planner is proposed. |
| Paper Nr: | 240 |
| Title: | Collision Avoidance of Intelligent Vehicle based on Networked High-speed Vision System |
| Authors: | Masahiro Hirano, Akihito Noda, Yuji Yamakawa and Masatoshi Ishikawa |
| Abstract: | We propose a driving safety support system (DSSS) that employs a high-speed vision system installed in the environment surrounding, for instance, highways, urban roads, and intersections. The aim of the system is to recognize potentially dangerous traffic situations, including those that are undetectable from a moving vehicle, and to use this information for supporting safe driving. The system consists of a vision network of synchronized high-speed cameras that are capable of acquiring images at one-millisecond intervals, and vehicles that are capable of communicating with this network through communication hubs. We conducted collision avoidance experiments and demonstrated that, by introducing high-speed vision, the proposed system can resolve the issue of slow reaction time, which is common to environmental vision systems. |
| Paper Nr: | 241 |
| Title: | Development of Autonomous Vehicle - Overview of Autonomous Driving Demonstration in ITS World Congress 2013 |
| Authors: | Naoki Suganuma and Yutaro Hayashi |
| Abstract: | Recently, fully automated autonomous vehicles have been developed, and field examinations in public road have also been conducted, especially in United States. In this paper, preparation of our laboratory toward field examination of the autonomous vehicle is reported. Additionally, overview of demonstration in the ITS world Congress 2013 (ITSWC2013) is reported. |
| Paper Nr: | 242 |
| Title: | The Curved Surface Visualization of the Expert Behavior for Skill Transfer Using Microsoft Kinect |
| Authors: | Kaoru Mitsuhashi, Hiroshi Hashimoto and Yasuhiro Ohyama |
| Abstract: | Method of teaching and inheriting for skill is almost oral. It is not quantitative but qualitative. Quantitative inheriting of skill is difficult. In this paper, after tracking of a subject's skill motion using Microsoft Kinect, a subject's motion is visualized as the curved surface. A curved surface is fitted in the positions of a subject's joint, or the direction of trajectories. Expert and beginner perform swimming and karate motion. After the motions are tracked, the trajectories of joints are transformed to a curved surface. The difference of an action between an expert and a beginner is extracted by investigating curvatures and form on the visualized curved surface. Therefore, we expected that technical skill is transferred easily. |
| Paper Nr: | 261 |
| Title: | Shape Memory Alloy-based High Phase Order Motor |
| Authors: | Claudio Rossi, Zongjian Yuan, Chao Zhang, Antonio Barrientos and William Coral |
| Abstract: | In this paper, we present our current work in the design and characterisation of a new shape memory alloy (SMA)-based High Phase Order Motor (HPOM). The motor can be used either in stepping mode or in servo mode of operation. Each phase of the motor consists of an SMA wire with a spring. The principle of operation of the HPOM is presented. In its operation the motor resembles a stepper motor though the actuation principles are different and hence has been characterised similar to a stepper motor.This motor can be actuated in either direction depending on which SMA is actuated, which are presented in this work. The motor is modelled and simulated and the results of simulations and experiments are presented. |
| Paper Nr: | 262 |
| Title: | Development of an Emergency Braking System for Teleoperated Vehicles Based on Lidar Sensor Data |
| Authors: | Johannes Wallner, Tito Tang and Markus Lienkamp |
| Abstract: | A lidar-based approach of an emergency braking system for teleoperated vehicles is presented. Despite the time delay for the communication link of a teleoperated system, the vehicle has to be able to react to emerging objects in time. Starting with intelligent sensor data processing, reliable information is computed. An adapted particle filter algorithm tracks moving points to calculate their mean velocity, used for the prediction of surrounding moving objects. Further, in order to interpret this information, a situation assessment based on an intervention concept derived from Kamm’s circle is implemented. A motion prediction of possible trajectories of the ego-vehicle results in a clear decision-making process. All calculations are made at the raw data level and can be done online. Through artificial objects being included in real sensor data, the methodology was validated. |
| Paper Nr: | 263 |
| Title: | A Model for Robotic Hand Based on Fibonacci Sequence |
| Authors: | Anna Chiara Lai, Paola Loreti and Pierluigi Vellucci |
| Abstract: | We study a robot hand model involving Fibonacci sequence. Fingers are modeled via hyper-redundant planar manipulators. Binary controls rule the dynamics of the hand, in particular the extension and the rotation of each phalanx. By estabilishing a relation with Iterated Function Systems, we investigate the reachable workspace and its convex hull. Finally, we give an explicit characterization of the convex hull of the reachable workspace in a particular case. |
| Paper Nr: | 267 |
| Title: | Joint Stiffness Identification of a Heavy Kuka Robot with a Low-cost Clamped End-effector Procedure |
| Authors: | A. Jubien, G. Abba and M. Gautier |
| Abstract: | This paper proposes two new methods for the identification of static stiffnesses of multi degrees of freedom heavy industrial robots. They are based on a locked link joint procedure obtained with an end-effector fixed to the environment. The first method requires only measurements of motor positions and motor torques data computed from motor current measurements and manufacturer's drive gains. The second one needs a torque sensor to measure the interaction wrench between the clamped end-effector and the environment. These methods are being experimentally validated and compared on the 2 first joints of a 6 degrees of freedom heavy 500Kg payload industrial Kuka KR500 robot. |
| Paper Nr: | 279 |
| Title: | Multi-goal Trajectory Planning with Motion Primitives for Hexapod Walking Robot |
| Authors: | Petr Vaněk, Jan Faigl and Diar Masri |
| Abstract: | This paper presents our early results on multi-goal trajectory planning with motion primitives for a hexapod walking robot. We propose to use an on-line unsupervised learning method to simultaneously find a solution of the underlying traveling salesman problem together with particular trajectories between the goals. Using this technique, we avoid pre-computation of all possible trajectories between the goals for a graph based heuristic solvers for the traveling salesman problem. The proposed approach utilizes principles of self-organizing map to steer the randomized sampling of configuration space in promising areas regarding the multi-goal trajectory. The presented results indicate the proposed steering mechanism provides a feasible multi-goal trajectory in a less number of samples than an approach based on a priori known sequence of the goals visits. |
| Paper Nr: | 280 |
| Title: | Cooperative Guidance of Lego Mindstorms NXT Mobile Robots |
| Authors: | Julien Marzat, Hélène Piet-Lahanier and Arthur Kahn |
| Abstract: | This paper presents experimental results of cooperative guidance laws embedded on Lego Mindstorms NXT mobile robots for two types of missions. The first one is navigation to a waypoint as a fleet with collision and obstacle avoidance, following a model predictive control (MPC) framework. The second one is source localization, i.e., finding the maximum of a potential field, for which a distributed estimation and control strategy is proposed. Experiments show the ability to perform the two missions on these basic mobile robots, in spite of their limited computational resources. In particular, the search for the optimal control sequence through a dedicated discretization of the command space makes it possible to implement real-time MPC. |
| Paper Nr: | 281 |
| Title: | Robot Workspace Monitoring with Redundant Structured Light Cameras - A Preliminary Investigation |
| Authors: | Hans Dermot Doran and Simon Marti |
| Abstract: | In this paper we propose the use of a redundant array of structured light scanning cameras to monitor a collaborative robot workspace. We present the model and suggest a minimum number of such cameras required to monitor a particular area. We then propose a concept for segmenting the workspace into different sub volumes to allow for different categories of obstacles. We then propose that a voting scheme will allow us to process multiple camera inputs in real-time in a safe fashion. We perform initial experiments and draw appropriate conclusions before defining further work. |
| Paper Nr: | 282 |
| Title: | Robot Local Navigation with Learned Social Cost Functions |
| Authors: | Noé Pérez-Higueras, Rafael Ramón-Vigo, Fernando Caballero and Luis Merino |
| Abstract: | Robot navigation in human environments is an active research area that poses serious challenges. Among them, human-awareness has gain lot of attention in the last years due to its important role in human safety and robot acceptance. The proposed robot navigation system extends state of the navigation schemes with some social skills in order to naturally integrate the robot motion in crowded areas. Learning has been proposed as a more principled way of estimating the insights of human social interactions. To do this, inverse reinforcement learning is used to derive social cost functions by observing persons walking through the streets. Our objective is to incorporate such costs into the robot navigation stack in order to “emulate” these human interactions. In order to alleviate the complexity, the system is focused on learning an adequate cost function to be applied at the local navigation level, thus providing direct low-level controls to the robot. The paper presents an analysis of the results in a robot navigating in challenging real scenarios, analyzing and comparing this approach with other algorithms. |
Posters
| Paper Nr: | 2 |
| Title: | Design and Development of a Wireless Emergency Start and Stop System for Robots |
| Authors: | D. García, R. Barber and M. A. Salichs |
| Abstract: | This paper develops a wireless communication system that connects robots with many remote control devices used by many different users. The most important issue of this system is safety. To get high safety level a quick and efficient communication system is required. The emergency system and its communication system must work in parallel and independently of the main control of the robot. The robot must react to an emergency signal, but as a previous step, it must make sure that the security system is enabled and it so must also have some knowledge of how many remote control devices are related and if any of them has lost the wireless connection. Besides all the research and design stage to develop the communication system, the system has been implemented and tested. To build it, a microcontroller Arduino Fio and a radio frequency module Xbee has been used. Finally, the system has been tested in order to characterize the communication system, settling, connection time and the battery life. |
| Paper Nr: | 10 |
| Title: | Proposal of Electronic Tag for Monitoring Environmental Conditions During Product Transportation |
| Authors: | Mikhaylov Dmitry, Smirnov Alexander, Khabibullin Timur, Froimson Mikhail, Zuykov Alexander, Sychov Nikolay, Grigorenko Andrey and Tolstaya Anastasia |
| Abstract: | The present invention is directed to an electronic tag for monitoring transportation of goods over long periods of time. It provides monitoring of all data regarding environmental conditions (for example, if an item should not be stored at more than some critical temperature, but had remained the entire time at just below the critical temperature, this also might be of interest). The tag reading device can communicate with the tag via a wired or wireless interface to transmit the data about conditions violations and display this information on its screen or forward it further to a PC or to a local area network. The paper provides the information about choice of the required for the system electronic components, tag, tag reading device, system software, monitoring methods, additional options, and system testing. The tag temperature registration accuracy is ± 0.50C. |
| Paper Nr: | 16 |
| Title: | Vehicle Parameter Independent Gain Matrix Selection for a Quadrotor using State-Space Controller Design Methods |
| Authors: | Graeme N. Wilson, Alejandro Ramirez-Serrano and Qiao Sun |
| Abstract: | With quadrotor use seeing extensive growth in recent years, the autonomous control of these Unmanned Aerial Vehicles (UAVs) is an increasing relevant and intersting field. In this paper a linear state-space approach at designing a stable hover controller in the presence of disturbances is presented along with simulation of control system performance. Additionally the design of a tracking system, for linear inertial position and yaw, is presented with simulation results. The gain matrix developed for this control system is independent of the specific quadrotor parameters, meaning that this same gain matrix can be used on a wide variety of quadrotors without modification. The hover and tracking controllers designed in this paper proved to perform well in simulation under perturbation disturbances and normally distributed disturbances on the UAVs linear speeds and angular speeds. |
| Paper Nr: | 25 |
| Title: | A Heuristic Framework for Path Planning the Largest Volume Object from a Start to Goal Configuration |
| Authors: | Evan Shellshear and Robert Bohlin |
| Abstract: | In this article we present a heuristic algorithm to compute the largest volume of an object in three dimensions that can move collision-free from a start configuration to a goal configuration through a virtual environment. The results presented here provide industrial designers with a framework to reduce the number of design iterations when designing parts to be placed in tight spaces. |
| Paper Nr: | 32 |
| Title: | Development of Wrist Bending Rehabilitation Robot |
| Authors: | Hyeon-Min Kim, Tae-Kyung Hong, Hyung-Je Cho and Gab-Soon Kim |
| Abstract: | This paper describes the wrist bending rehabilitation robot using a four-axis force/moment sensor. The robot can be used to exercise the wrist bending rehabilitation for severe stroke patients lying in bed wards or at home. The manufactured four-axis force/moment sensor which can detect two directional force Fx, Fy and two directional moment Mx, My, was attached to the developed rehabilitation robot and allows the rehabilitation robot to measure a bending force (Fx) exerted on a wrist, the signal force Fy and moments Mx, My which in turn allows the device to be used safely. The results of a characteristics test for the developed rehabilitation robot showed that it was safely operated while the wrist bending flexibility rehabilitation exercise was performed. Therefore, it is thought that the developed rehabilitation robot can be safely used with severe stroke patients. |
| Paper Nr: | 52 |
| Title: | A Compact Planar-patch Descriptor based on Color |
| Authors: | Eduardo Fernández-Moral, Javier González-Jiménez and Vicente Arévalo |
| Abstract: | The representation of the world upon planar patches has proven to be simple, robust and useful for a variety of robotic tasks, including SLAM, autonomous navigation, or scene recognition. In this work we investigate how to incorporate color information into such representation to improve the matching of planar patches while maintaining the model compactness, which is essential for real-time applications. We propose a descriptor based on the dominant color of the patch, which is defined as the center of the biggest cluster in the patch histogram. In the paper, different color spaces and methods for extracting the dominant color are analyzed. We compare this descriptor with a recent proposal (saturated hue based histogram) and provide some conclusions on the trade-off between their descriptiveness and compactness. Finally, we present experimental results showing how our color descriptor can be exploited to increase the efficiency of both: plane-based place recognition and planar patch categorization. |
| Paper Nr: | 54 |
| Title: | Sliding Mode Control of Biglide Planar Parallel Manipulator |
| Authors: | Mustapha Litim, Benyamine Allouche, Abdelhafid Omari, Antoine Dequidt and Laurent Vermeiren |
| Abstract: | This work presents the control of a two-degree of freedom parallel manipulator using nonlinear sliding mode approach. The aim is to achieve a robust control for trajectory tracking. The control is based on the inverse dynamic model in the Cartesian space of the parallel manipulator. Kinematic analysis are also discussed. To guarantee the high performance on the tracking control. Biglide robot requires full knowledge on the system’s dynamics. In this paper, some important properties of the parallel manipulators are considered to develop a sliding mode controller which can drive the movement tracking error to zero asymptotically. Numerical simulations are completed to show the effectiveness of the approach for a large parameter variations. |
| Paper Nr: | 62 |
| Title: | Adaptive Strategies for Collaborative Work with Scale Quad-rotors |
| Authors: | José Cesáreo Raimúndez and José Luis Camaño |
| Abstract: | The purpose of this paper is to present strategies for the control of movement of rigid bodies via force actuators, possibly redundant. After a nonlinear feedback linealization of the considered dynamic models and the application of a suitable controller, an adaptive neural network based control component is incorporated in order to cope with modeling errors and disturbance rejection. An online sequential quadratic programing optimization with equality and inequality constraints assures an adequate configuration of actuator forces. Application to collaborative work in the transportation of a rigid body using a squadron of scale quad-rotors is studied. |
| Paper Nr: | 67 |
| Title: | Detection of Mechanical Play of Revolute Robot Joint |
| Authors: | Radim Luža and František Zboril |
| Abstract: | This article introduces a method of detection of mechanical play of revolute joint based on recognition of impacts caused by the play. The method uses inexpensive acceleration measuring device with limited sampling frequency. The impact is recognized indirecly according to oscillation of mechanical oscilator. The method was tested on real servo drive Dynamixel AX-12A. |
| Paper Nr: | 76 |
| Title: | A Vision System for Autonomous Satellite Grapple with Attitude Thruster |
| Authors: | Haidong Hu, Xiaoyan Mao, Zhibin Zhu, Chunling Wei and Yingzi He |
| Abstract: | This paper describles an experiment of a binocular vision-based system for positioning the thruster nozzle on the satellite mockup. Images of the thruster are obtained using two cameras in order to determine the thruster’s 3D position. At the beginning the thruster is selected manually, and then a local image region is extracted from the raw image. Subsequently, a Canny detector algorithm is used in the local image region to acquire the edge roadmap, and a Hough Transform algorithm is performed to detect the features with circles. Then, a curving fitting method is employed to determine the position of the center of the thruster nozzle., The end effector keeps tracking the target thruster to the distance of 0.1 meter and grasps the target by prodicting its trajectory. The experiment has shown that the system is robust to camera/target relative motions and performs approaching and grappling procedures on satellite mockup successfully. |
| Paper Nr: | 140 |
| Title: | Complex Motion Planning for NAO Humanoid Robot |
| Authors: | Walaa Gouda and Walid Gomaa |
| Abstract: | In this paper, we introduce an integrated approach that enables a humanoid robot to plan and robustly execute whole body motions including stepping over, climbing up or down obstacles as well as climbing up straight staircase using only onboard sensing. Reliable and accurate sequence of motions for humanoid robots operating in complex indoor environments is a prerequisite for robots to fulfill high level tasks. The design of complex dynamic motions is achievable only through the use of robot kinematics. Based on the recognized object from the robot database, using the robot camera, a sequence of actions for avoiding that object is executed. As demonstrated in simulation as well as real world experiments with NAO humanoid, NAO can reliably execute robustly whole body movements in cluttered, multi-level environments containing objects of various shapes and sizes. |
| Paper Nr: | 142 |
| Title: | Strategy-planned Q-learning Approach for Multi-robot Task Allocation |
| Authors: | H. Hilal Ezercan Kayir and Osman Parlaktuna |
| Abstract: | In market-based task allocation mechanism, a robot bids for the announced task if it has the ability to perform the task and is not busy with another task. Sometimes a high-priority task may not be performed because all the robots are occupied with low-priority tasks. If the robots have an expectation about future task sequence based-on their past experiences, they may not bid for the low-priority tasks and wait for the high-priority tasks. In this study, a Q-learning-based approach is proposed to estimate the time-interval between high-priority tasks in a multi-robot multi-type task allocation problem. Depending on this estimate, robots decide to bid for a low-priority task or wait for a high-priority task. Application of traditional Q-learning for multi-robot systems is problematic due to non-stationary nature of working environment. In this paper, a new approach, Strategy-Planned Distributed Q-Learning algorithm which combines the advantages of centralized and distributed Q-learning approaches in literature is proposed. The effectiveness of the proposed algorithm is demonstrated by simulations on task allocation problem in a heterogeneous multi-robot system. |
| Paper Nr: | 159 |
| Title: | A Performance Evaluation of Surface Normals-based Descriptors for Recognition of Objects Using CAD-Models |
| Authors: | Carlos Manuel Mateo, Pablo Gil and Fernando Torres |
| Abstract: | This paper describes a study and analysis of surface normal-base descriptors for 3D object recognition. Specifically, we evaluate the behaviour of descriptors in the recognition process using virtual models of objects created from CAD software. Later, we test them in real scenes using synthetic objects created with a 3D printer from the virtual models. In both cases, the same virtual models are used on the matching process to find similarity. The difference between both experiments is in the type of views used in the tests. Our analysis evaluates three subjects: the effectiveness of 3D descriptors depending on the viewpoint of camera, the geometry complexity of the model and the runtime used to do the recognition process and the success rate to recognize a view of object among the models saved in the database. |
| Paper Nr: | 171 |
| Title: | Multi-robotic System with Self-organization for Search of Targets in Covered Area |
| Authors: | Jolana Sebestyénová and Peter Kurdel |
| Abstract: | The paper introduces the multi-robot area coverage problem, wherein a group of robots must inspect every point of a 2-dimensional test environment and surround all contaminations (or enemies) found. Self-organizing robotic systems are able to accomplish complex tasks in a changing environment, using local interactions among individual agents and local environment without an external global control. Our interest in this area is motivated by an involvement in a project with a goal to solve tasks of difficult area coverage and surveillance by a large team of small autonomous robots. In the paper, the architecture to achieve this is described, and simulation results are presented to compare efficiency of coverage of the area and surround of found targets using robots groups having different sensors ranges. |
| Paper Nr: | 185 |
| Title: | Visual Odometry using the Global-appearance of Omnidirectional Images |
| Authors: | F. Amorós, L. Payá, D. Valiente, A. Gil and O. Reinoso |
| Abstract: | This work presents a purely visual topologic odometry system for robot navigation. Our system is based on a Multi-Scale analysis that allows us to estimate the relative displacement between consecutive omnidirectional images. This analysis uses global appearance techniques to describe the scenes. The visual odometry system also makes use of global appearance descriptors of panoramic images to estimate the phase lag between consecutive images and to detect loop closures. When a previous mapped area is recognized during the navigation, the system re-estimates the pose of the scenes included in the map, reducing the error of the path. The algorithm is validated using our own database captured in an indoor environment under real dynamic conditions. The results demonstrate that our system permits estimating the path followed by the robot with accuracy comparing to the real route. |
| Paper Nr: | 206 |
| Title: | Building a ROS Node for a NMEA Depth and Temperature Sensor |
| Authors: | Robert Codd-Downey, Michael Jenkin and Andrew Speers |
| Abstract: | Although many commercially available robots ship with a version of ROS this is not as true for many external sensors. There is a lack of ROS support for many devices and sensors one might use to extend the capabilities of a robot. As robots are deployed in more complex environments there is the need for more specialized sensors. In particular in the aquatic domain there is the need for support for depth sounders. This paper describes the design and construction process for building a ROS node for a NMEA 0183 compliant depth and temperature transducer and a strategy for extending this design to other NMEA devices. |
| Paper Nr: | 255 |
| Title: | A Stable Tracking Control of Skid Steered Mobile Platform |
| Authors: | Seungwoo Jeon, Wootae Jeong and Duckshin Park |
| Abstract: | The skid steering technique has been widely used in controlling mobile vehicles without steering wheels because of light-weight and relatively simple structural configuration for steering motion control. However, since the skid controlled mobile platform system is based on nonholonomic constraint, it is essential to linearizing the nonlinear dynamic model of the vehicle for improving the stability of traction control. Recently developed ventilation duct cleaning robot with moving brushing arm also utilizes the skid steering system for traction control. Since the moving brush arm may change the mass center of the platform and effect on dynamics consequently, a new control scheme is suggested and simulated to achieve the stable trajectory tracking and driving motion of the developed mobile platform |
| Paper Nr: | 273 |
| Title: | Development of a Parallel Link Arm for Object Handling by Wheeled Mobile Robot |
| Authors: | Toyomi Fujita and Hiroshi Sugawara |
| Abstract: | This paper presents a parallel link arm for a wheeled mobile robot. A parallel mechanism is useful for a mobile robot because it has more advantages on high output power than serial link. Conventional parallel mobile manipulators have not been able to perform handling task such as picking up an object on the floor. Developed parallel link arm in this study has a hand which directs downward. It is mounted on the robot with the link for swinging so that it is able to carry an object with handling in wide area. This paper describes development of the parallel link arm and analyses its kinematics. We also consider basic motions of the arm for object handling tasks. Experimental results demonstrated the usefulness of developed parallel link arm for object handling tasks by a wheeled mobile robot. |
| Paper Nr: | 284 |
| Title: | Experimental Evaluation of a Modified Obstacle Based Potential Field Algorithm for an Off-road Mobile Robot |
| Authors: | Rickard Nyberg, George Nikolakopoulos and Dariusz Kominiak |
| Abstract: | This article presents an experimental evaluation of a modified obstacle based artificial potential field algorithm for an off-road mobile robot. The first contribution of the presented approach concerns the transformation of the artificial potential field method for the guidance of the vehicle and obstacle avoidance, in order to make it suitable for utilising a visual feedback. The visual feedback is relying on a depth image, provided by the low cost kinect sensor. The second contribution concerns the proposal of a novel scheme for the identification and perception of obstacles. Based on the proposed methodology, the vehicle is capable of categorising the obstacles based on their height in order to alter the calculated forces, for enabling a cognitive decision regarding their avoidance or the driving over them, by utilising the robot’s off road capabilities. The proposed scheme is highly suggested for off road robots, since in the normal cases, the existence of small rocks, branches, etc. can be accidentally identified as obstacles that could make the robot to avoid them or block its further movement. The performance of the proposed modified potential field algorithm has been experimentally applied and evaluated in multiple robotic exploration scenarios, where from the obtained results the efficiency and the advantages of such a modified scheme have been depicted. |
| Paper Nr: | 288 |
| Title: | Towards Establishing and Maintaining Autonomous Quadrotor Formations |
| Authors: | Audrow J. Nash, Terrill E. Massey, Christopher J. Wesley, Saketh Simha Kosanam and James M. Conrad |
| Abstract: | Autonomous aerial formations of multiple quadrotors can be used for payload manipulation and surveillance, and often require an external system for computation or control, in order to be decentralized. By having centrally controlled quadrotors, swarm applications can be realized without the limitations of an external system. In this paper, an algorithm is proposed to establish a swarm formation of centrally controlled quadrotors. First, a method of localization and motion planning is discussed for a single quadrotor. Next, the behavior of quadrotor swarm formations with centralized control is described. Lastly, the future direction of this research is explained. |
| Paper Nr: | 295 |
| Title: | Development of Therapeutic Expression for a Cat Robot in the Treatment of Autism Spectrum Disorders |
| Authors: | Bo Hee Lee, Ju-young Jang, Keum-hi Mun, Ja Young Kwon and Jin Soun Jung |
| Abstract: | The purpose of this research is to develop a therapeutic expression for the use of early treatment that will improve the social interactions of children with autism spectrum disorders (ASD). In order to satisfy the purpose, we choose a cat character after surveying requirements and summarize the required actions for a treatment as hugging, eye contacts, copies of body movements and reactions to negative behaviours. The robot has a face mechanism that can express the emotion and a body mechanism to perform hand gesture. We also designed a system controller and sensor interfaces to control its body or interact with children. All the use history of the robot is stored at the memory device to analyze the play patterns of the patient and also used to make the treatment program that can be utilized in the specialized clinic. In this study, the therapeutic expression for the treatment of ASD is suggested and ported in a cat robot, and verified with real action experiment of those functions. This study is kinds of preliminary result before developing a treatment therapy for ASD children using perfect cat robot that has outer skin and furry coat, and followed by expression research for the suitable program that can be applied in the real treatment field. |
Area 3 - Signal Processing, Sensors, Systems Modelling and Control
Full Papers| Paper Nr: | 35 |
| Title: | Development of Training Simulator for Sway Suppression Skills on Shipboard Rotary Cranes |
| Authors: | Yusaku Matsuda, Shoma Fushimi and Kazuhiko Terashima |
| Abstract: | In this paper, we develop the operational training system by teaching control input to crane operators. In particular, it is applied to the sway suppression control of load, by utilizing optimal control input. If crane operators can replicate its control input, they can operate crane suppressing the load sway, and hope the advance of training effect. Firstly, we build a shipboard rotary crane simulator, and verify the validity of the training simulator by transfer simulation. Nextly, it presents a sway suppression control method to obtain control input for crane operators, and proposes the training system to teach its control input to operators. Finally, the crane simulator integrates this training system, and the proposed training system verifies the validity by subjects experiments. |
| Paper Nr: | 53 |
| Title: | Modeling and H∞ Composite Control of the Coupled Hysteretic Dynamics in Piezoelectric Micro-displacement Systems |
| Authors: | Liang Tang, Lei Liu and Xin Guan |
| Abstract: | This paper investigates the modeling and H∞ composite control of the coupled hysteretic dynamics in a piezoelectric micro-displacement system (PMS). First, the coupled multi-field hysteretic dynamics with physical meanings is presented for PMS. Next, the composite control analysis of the hysteretic dynamics is proposed. Then, a H∞ synthesis controller is designed by using the simplified hysteretic dynamics. To enhance the H∞ performance, the inversion-based feedforward compensation is augmented. The proposed H∞ feedback control and the inversion-based feedforward can be designed separately. Finally, the experimental studies are provided to demonstrate the proposed H∞ composite control approach. |
| Paper Nr: | 57 |
| Title: | Contactless Thin-Layered Torque Sensor Module with Fully-digital Signal Processing Circuit |
| Authors: | Chi-Ting Yeh, Nan-Chyuan Tsai, Hsin-Lin Chiu and Chung-Yang Sue |
| Abstract: | A contactless thin-layered torque sensor with fully-digital signal processing circuit is proposed in this work. The mechanical structure of the torque sensor is an orange-slice-alike flexible body. Two links, beforehand aligned, with B/W stripes play the role of optical grating by resolution as no any torque applied to the shaft. As long as the orange-slice-alike flexible body, sandwiched by the aforesaid links, is subject to an external torque applied, a twisted angle is induced between the two thin photo-grating discs. Two sets of photo detector cooperate with the two discs with optical gratings to generate two pulse sequences. Therefore, a time delay between these two pulse sequences can be acquired as long as the shaft is twisted by a torque. A counter IC is employed to quantify this time delay in terms of the torque applied, and the time period, in terms of rotational speed of shaft. One of merits of the proposed torque sensor is: real-time measurement on torque applied becomes feasible even if the shaft, subject to external torque, is rotating at high speed. Another advantage of the fully-digital signal processing circuit is: no need to conduct A/D conversion and free of noise, cross-talk and EMI (Electromagnetic Interference). |
| Paper Nr: | 65 |
| Title: | Object Contour Reconstruction using Bio-inspired Sensors |
| Authors: | Christoph Will, Joachim Steigenberger and Carsten Behn |
| Abstract: | This work is inspired and motivated by the sophisticated mammals sense organ of touch: vibrissa. Mammals, especially rodents, use their vibrissae, located in the snout region – mystacial vibrissae – to determine object contacts (passive mode) or to scan object surfaces (active mode). Here, we focus on the passive mode. In order to get hints for an artificial sensing prototype, we set up a mechanical model in form of a long slim beam which is one-sided clamped. We investigate in a purely analytical way a quasi-static sweep of the beam along a given profile, where we assume that the profile boundary is strictly convex. This sweeping procedure shows up in two phases, which have to be distinguished in profile contact with the tip and tangentially contact (between tip and base). The analysis eventuates in a phase decision criterion and in a formula for the contact point. These are the main results. Moreover, based on the observables of the problem, i.e. the clamping moment and the clamping forces, which are the only information the animal relies on, a reconstruction of the profile is possible – even with added uncertainty mimicking noise in experimental data. |
| Paper Nr: | 66 |
| Title: | Collaborative Kalman Filtration - Bayesian Perspective |
| Authors: | Kamil Dedecius |
| Abstract: | The contribution studies the problem of collaborative Kalman filtering over distributed networks with or without a fusion center from the theoretically consistent Bayesian perspective. After presenting the Bayesian derivation of the basic Kalman filter, we develop a versatile method allowing exchange of observations among the network nodes and their local incorporation. A probabilistic nodes selection technique based on prior knowledge of nodes performance is proposed to reduce the communication requirements. |
| Paper Nr: | 68 |
| Title: | Swing-up Control of a Single Inverted Pendulum on a Cart With Input and Output Constraints |
| Authors: | Meta Tum, Giyeong Gyeong, Jae Heon Park and Young Sam Lee |
| Abstract: | In this paper we propose a new swing-up strategy for a single inverted pendulum. The proposed method has a feature that can handle the limitation of the pendulum-rail length and actuator constraints using both feedforward and feedback control. The feedforward trajectories are generated by solving an optimal control problem having two-point boundary conditions. The limitation of the rail length and the actuator constraints are taken into account in the problem formulation. Feedback control is combined with the feedforward control to compensate the deviation between the desired trajectories and actual trajectories. The experimental results of the proposed strategy show that it has a good swing-up performance while satisfying all the imposed constraints. |
| Paper Nr: | 69 |
| Title: | Passivity Preserving Multipoint Model Order Reduction using Reflective Exploration |
| Authors: | Elizabeth Rita Samuel, Luc Knockaert and Tom Dhaene |
| Abstract: | Reduced state-space models obtained by model order reduction methods must be accurate over the whole frequency range of interest and must also preserve passivity. In this paper, we propose multipoint reduction technique using reflective exploration for adaptively choosing the expansion points. The projection matrices obtained from the expansion points are merged to form the overall projection matrix. In order to obtain a more compact model the projection matrix is truncated based on its singular values. Finally, the reduced order model is obtained, while ensuring that the passivity of the reduced system is preserved during the reduction process. |
| Paper Nr: | 75 |
| Title: | Sliding Mode Control of Linear Time-varying Systems - Application to Trajectory Tracking Control of Nonlinear Systems |
| Authors: | Yasuhiko Mutoh and Nao Kogure |
| Abstract: | This paper concerns with the sliding mode controller design method for linear time-varying systems. For this purpose, using the time-varying pole placement technique, the state feedback is designed first so that the time-varying closed loop system is equivalent to the standard linear time invariant system. Then, conventional sliding mode controller design method is applied to this time invariant system to obtain the control input. Finally, using the time-varying transformation matrix, this sliding mode control input is put back to the control input for the original system. In this paper, this controller is applied to the trajectory tracking control problem for nonlinear systems. |
| Paper Nr: | 113 |
| Title: | L1 Adaptive Output Feedback Controller with Operating Constraints for Solid Oxide Fuel Cells |
| Authors: | Lei Pan, Chengyu Cao and Jiong Shen |
| Abstract: | Control on solid oxide fuel cells (SOFC) is challenging due to its nonlinearity, time-varying uncertainties, tight operating constraints and modeling difficulties. The L1 adaptive output feedback controller for systems of unknown relative degree is introduced for the SOFC output voltage control in this paper. It allows for fast and robust adaptation, and provides improved transient performance. Its advantages of not enforcing a strictly positive real condition along with the low-pass filtered control signal bring it the potential to be applied in wide industrial processes. In the study of the SOFC control, a dynamic SOFC model is first built; then a L1 adaptive output feedback controller is designed only using the nominal working conditions of the SOFC model. Through setting the operating constraints at proper locations, the closed-loop stability is maintained in the presence of hard constraints by the symmetric structure of the L1 adaptive control loop. A simulation comparison is made in the SOFC constant voltage control process between the L1 adaptive controller and a linear disturbance model predictive controller (DMPC) for their almost equal complexity in designs. The result shows the advantage of the L1 adaptive controller in disturbance rejections for its faster transient response. |
| Paper Nr: | 139 |
| Title: | On the Stabilization of the Flexible Manipulator - Liapunov based Design. Robustness. |
| Authors: | Daniela Danciu, Dan Popescu and Vladimir Rasvan |
| Abstract: | This work deals with dynamics and control of the flexible manipulator viewed as a system with distributed parameters. It is in fact described by a mixed problem (with initial and boundary conditions) for a hyperbolic partial differential equation, the flexible manipulator being assimilated to a rod. As a consequence of the deduction of the model via the variational principle of Hamilton from Rational Mechanics, the boundary conditions result as “derivative” in the sense that they contain time derivatives of higher order (in comparison with the standard Neumann or Robin type ones). To the controlled model there is associated a control Liapunov functional by using the energy identity which is well known in the theory of partial differential equations. Using this functional the boundary stabilizing controller is synthesized; this controller ensures high precision positioning and additional boundary damping. All this synthesis may remain at the formal level, mathematically speaking. The rigorous results are obtained by using a one to one correspondence between the solutions of the boundary value problem and of an associated system of functional differential equations of neutral type. This association allows to prove in a rigorous way existence, uniqueness and well posedness. Moreover, in several cases there is obtained global asymptotic stability which is robust with respect to the class of nonlinear controllers - being in fact absolute stability. The paper ends with conclusions and by pointing out possible extensions of the results. |
| Paper Nr: | 145 |
| Title: | Guaranteed State and Parameter Estimation for Nonlinear Dynamical Aerospace Models |
| Authors: | Qiaochu Li, Carine Jauberthie, Lilianne Denis-Vidal and Cherfi Zohra |
| Abstract: | This paper deals with parameter and state estimation in a bounded-error context for uncertain dynamical aerospace models when the input is considered optimized or not. In a bounded-error context, perturbations are assumed bounded but otherwise unknown. The parameters to be estimated are also considered bounded. The tools of the presented work are based on a guaranteed numerical set integration solver of ordinary differential equations combined with adapted set inversion computation. The main contribution of this work consists in developing procedures for parameter estimation whose performance is highly related with the input of system. In this paper, a comparison with a classical non-optimized input is proposed. |
| Paper Nr: | 151 |
| Title: | Nonlinear Feedback Control and Artificial Intelligence Computational Methods applied to a Dissipative Dynamic Contact Problem |
| Authors: | Daniela Danciu, Andaluzia Cristina Matei, Sorin Daniel Micu and Ionel Rovenţa |
| Abstract: | In this paper we consider a vibrational percussion system described by a one-dimensional hyperbolic partial differential equation with boundary dissipation at one extremity and a normal compliance contact condition at the other extremity. Firstly, we obtain the mathematical model using the Calculus of variations and we prove the existence of weak solutions. Secondly, we focus on the numerical approximation of solutions by using a neuromathematics approach – a well-structured numerical technique which combines a specific approach of Method of Lines with the paradigm of Cellular Neural Networks. Our technique ensures from the beginning the requirements for convergence and stability preservation of the initial problem and, exploiting the local connectivity of the approximating system, leads to a low computational effort. A comprehensive set of numerical simulations, considering both contact and non-contact cases, ends the contribution. |
| Paper Nr: | 184 |
| Title: | Numerical Simulation and Automatic Control of the pH Value in an Industrial Blunting System |
| Authors: | Vlad Mureşan, Adrian Groza, Mihail Abrudean and Tiberiu Coloşi |
| Abstract: | A solution for the pH control of the residual water in an industrial blunting system is proposed. The technological process associated to the blunting system is decomposed in four sub-processes connected in series and in parallel, each of them being a distributed parameter one. The mathematical models of the sub-processes are expressed using partial differential equations. Both this procedure and the advanced structure of the control system generate very high control performances. For the numerical simulation of the control system, a numerical method based on the Matrix of Partial Derivatives of the State Vector, associated with Taylor series is proposed. This method permits the numerical simulation of the systems that include in their structure distributed parameter processes. The conducted simulations proved high accuracy of our original method. |
| Paper Nr: | 194 |
| Title: | Testing of Sensor Condition Using Gaussian Mixture Model |
| Authors: | Ladislav Jirsa and Lenka Pavelkova |
| Abstract: | The paper describes a method of sensor condition testing based on processing of data measured by the sensor using a Gaussian mixture model with dynamic weights. The procedure is composed of two steps, off-line and on-line. In off-line stage, fault-free learning data are processed and described by a probabilistic mixture of regressive models (mixture components) including a transition table between active components. It is assumed that each component characterises one property of data dynamics and just one component is active in each time instant. In on-line stage, tested data are used for transition table estimation compared with the fault-free transition table. The crossing of given level of difference announces a possible fault. |
| Paper Nr: | 210 |
| Title: | Dynamical Model of Asphalt-Roller Interaction During Compaction |
| Authors: | Syed Asif Imran, Fares Beainy, Sesh Commuri and Musharraf Zaman |
| Abstract: | Proper and uniform compaction during construction is of utmost importance for the long term performance of asphalt pavement. Variations in the conditions of freshly laid pavements require adjustment of the compaction effort in order to obtain uniform and adequate density. One of the goals of on-going research in Intelligent Compaction (IC) is the development of adaptive feedback control mechanism to adjust the compaction effort according to the field and pavement conditions. Such feedback control systems require a good understanding of compaction dynamics. In this study, a dynamical model is developed to study the interaction between a moving vibratory roller and the underlying asphalt pavement during compaction. The asphalt pavement is represented as a lumped element model with visco-elastic-plastic properties. A procedure is presented to estimate the parameters of this model from standard tests on asphalt mix conducted in the laboratory. The combined roller-pavement dynamical model is used to replicate field compaction of an asphalt pavement using a vibratory roller. Numerical simulation results indicate good agreement with results observed during compaction of pavements in the field. Comparison between the simulation results and the results collected from the actual pavement construction job show that the model could be used as a mathematical basis for the development of advanced compaction methods. |
| Paper Nr: | 211 |
| Title: | Detailed Modeling and Calibration of a Time-of-Flight Camera |
| Authors: | Christoph Hertzberg and Udo Frese |
| Abstract: | In this paper we propose a physically motivated sensor model of Time-of-Flight cameras. We provide methods to calibrate our proposed model and compensate all modeled effects. This enables us to reliably detect and filter out inconsistent measurements and to record high dynamic range (HDR) images. We believe that HDR images have a significant benefit especially for mapping narrow-spaced environments as in urban search and rescue. We provide methods to invert our model in real-time and gain significantly higher precision than using the vendor-provided sensor driver. In contrast to previously published purely phenomenological calibration methods our model is physically motivated and thus better captures the structure of the different effects involved. |
Short Papers
| Paper Nr: | 26 |
| Title: | Adaptive Gauss Hermite Filter for Parameter and State Estimation of Nonlinear Systems |
| Authors: | Aritro Dey, Manasi Das, Smita Sadhu and T. K. Ghoshal |
| Abstract: | This paper presents an adaptive Gauss Hermite filter for nonlinear signal models in the situation when the measurement noise statistics is unknown. The proposed nonlinear filter, based on the Gauss Hermite quadrature rule, can ensure satisfactory estimation performance despite the problem of unknown measurement noise statistics by online adaptation. Results of Monte Carlo Simulation demonstrate the efficacy of the proposed filter for joint estimation of parameters and states using an object tracking problem. |
| Paper Nr: | 44 |
| Title: | Can Random Noise Injection Eliminate Noise? - Simulation and Hardware Implementation |
| Authors: | Suleyman Kondakci |
| Abstract: | Noise, found in all types of instrumentation and signal processing systems, has been a great challenge to tackle, especially, in biomedical signal processing tasks. Often, low-frequency and low power measurement signals are used in biomedical signal applications. This work is aimed at modeling and developing a simple, efficient, and inexpensive front end signal conditioner applying the cowpox approach to low-power analog signal measurements. We focus here on the simulation and implementation of a signal conditioner for the evaluation of its feasibility and efficiency based on the cost and accuracy constraints. As briefly outlined below, this article can serve as a model for facilitating the construction of semi–digital filters that can be applied to denoising of signals with low-frequency and very weak amplitude levels. |
| Paper Nr: | 45 |
| Title: | Digital Self-tuning Control for Pressure Process |
| Authors: | Gediminas Liaucius and Vytautas Kaminskas |
| Abstract: | Two digital control systems - Self-tuning PID (Proportional-Integral-Derivative) Control and Predictor-based self-tuning control with constraints - for the continuous-time pressure process control are presented in this paper. The digital self-tuning PID control with optimization of closed-loop parameters and sampling period is proposed. The multidimensional optimization problem of closed-loop parameters and sampling period is solved by subcomponent search method that enables dividing the problem to one-dimensional optimization problems. The golden section search is adjusted to solve those – one-dimensional - optimization problems. The predictor-based self-tuning control with constraints is adapted for both minimum-phase and nonminimum-phase process models. The control quality of pressure process of both control systems has been experimentally investigated. The results of experimental analysis demonstrate that the digital self-tuning PID control with optimization is more efficient as compared to predictive-based self-tuning control with constraints for pressure process. |
| Paper Nr: | 50 |
| Title: | Adaptive Filtering in Electricity Spot Price Models |
| Authors: | Shin Ichi Aihara and Arunabha BAGCHI |
| Abstract: | We study the adaptive filtering for risk premium and system parameters in electricity futures modes. Introducing the jump augmented Vasicek model as the spot price mode, the factor model of the electricity futures is constructed as the stochastic hyperbolic systems with jumps. Representing the main spike phenomena of the electricity spot price from one observed futures data by proxy, the filtering of the stochastic risk premium and its system parameters are developed in a Gaussian framework. By using the parallel filtering algorithm, the online system parameter estimation procedure is proposed. |
| Paper Nr: | 60 |
| Title: | Multi-loop Control Using Gershgorin and Ostrowski Bands |
| Authors: | C. Le Brun, E. Godoy, D. Beauvois, N. Doncque and R. Noguera |
| Abstract: | The goal of this paper is to develop a new method of decentralized control tuning. This method is based on Nyquist-Arrays and independently designs monovariable controllers for each loop of the plant while ensuring the robust stability of the multivariable system. It works on the optimization of a frequency criterion using the controller’s design parameters. PID controllers have been chosen in this study because of their good performances for most applications. Finally, the proposed method allows to achieve good performances and the stability is ensured thanks to the analysis of Gershgorin and Ostrowski bands. |
| Paper Nr: | 84 |
| Title: | Linear Switching System Identification Applied to Blast Furnace Data |
| Authors: | Amir H. Shirdel, Kaj-Mikael Björk, Markus Holopainen, Christer Carlsson and Hannu T. Toivonen |
| Abstract: | Switching systems are dynamical systems which can switch between a number of modes characterized by different dynamical behaviors. Several approaches have recently been presented for experimental identification of switching system, whereas studies on real-world applications have been scarce. This paper is focused on applying switching system identification to a blast furnace process. Specifically, the possibility of replacing nonlinear complex system models with a number of simple linear models is investigated. Identification of switching systems consists of identifying both the individual dynamical behavior of model which describes the system in the various modes, as well as the time instants when the mode changes have occurred. In this contribution a switching system identification method based on sparse optimization is used to construct linear switching dynamic models to describe the nonlinear system. The results obtained for blast furnace data are compared with a nonlinear model using Artificial Neural Fuzzy Inference System (ANFIS). |
| Paper Nr: | 98 |
| Title: | Active Vibration Control of a Super Element Model of a Thin-walled Structure |
| Authors: | Nader Ghareeb and Rüdiger Schmidt |
| Abstract: | Reducing vibration in flexible structures has become a pivotal engineering problem and shifted the focus of many research endeavors. One technique to achieve this target is to implement an active control system. A conventional active control system is composed of a vibrating structure, a sensor to perceive the vibration, an actuator to counteract the influence of disturbances causing vibration, and finally a controller to generate the appropriate control signals. In this work, different linear controllers are used to attenuate the vibrations of a cantilevered smart beam excited by its first eigenmode. A finite element (FE) model of the smart beam is initially created and then modified by using experimental data. The FE model is then reduced to a super element (SE) model with a finite number of degrees of freedom (DOF). Controllers are applied directly to the SE and the results are presented and compared. |
| Paper Nr: | 112 |
| Title: | On the Asymptotic Stability Analysis of a Certain Type of Discrete-time 3-D Linear Systems |
| Authors: | Guido Izuta |
| Abstract: | This work is concerned with the analysis of 3-d (3-dimensional) systems. The aim is to establish conditions that guarantee the asymptotic stability of these kinds of systems. To accomplish it, the Lagrange candidate solutions method for partial difference equations is adopted here. We show that the systems are asymptotically stable if the entries of the matrices of their state space descriptions yield a solution in the Lagrange solution sense. Furthermore, the particular cases in which the matrices can be turned into a diagonal matrix by means of the canonical transformation is studied in order to figure out the role of the eigenvalues on the stability conditions. |
| Paper Nr: | 127 |
| Title: | Providing Water Parameters Monitoring Data through Interoperable Web Services |
| Authors: | Anca Hangan, Lucia Vacariu, Octavian Cret and Marian Muste |
| Abstract: | The paper describes the design and development of a water parameters monitoring system for rivers. The system exposes a set of web services that can act as support for decision making in pollution control or as data provider for a wide range of informational, educational or research applications. A prototype based on the proposed system design was build and experiments were made on Somes River in Romania. Our prototype contains web based and mobile applications that provide access to the measurements made by the sensors and to the historical information as well. |
| Paper Nr: | 156 |
| Title: | Compensation of Parasitic Effect in Homing Loop with Strapdown Seeker via PID Control |
| Authors: | Ju-Hyeon Hong and Chang-Kyung Ryoo |
| Abstract: | Due to seeker delay and coupling with body motion, a strapdown seeker has not been widely used for missiles though it makes the missile cost cheaper. In this paper, a homing loop design based on PID controller for missiles with a strapdown seeker is suggested. The PID controller produces body rate command, instead of estimating line-of-sight(LOS) rate for the proportional navigation guidance. Stability analysis for linear homing loop has been done to select controller gains. The performance of the designed terminal homing loop for a small tactical missile against a moving target, where the missile’s strapdown seeker includes uncertain image processing delay, is verified through full nonlinear 6-DOF simulations. |
| Paper Nr: | 158 |
| Title: | Differential Evolution Algorithm Based Spatial Multi-sensor Image Fusion |
| Authors: | Veysel Aslantas and Emre Bendes |
| Abstract: | In this paper, a new optimised region based multi-sensor image fusion method is presented. The proposed method works on spatial domain. Differential evolution algorithm is used to optimize the contribution of the input images to fused images based on regions. The method was compared visually and quantitatively with Laplacian Pyramid (LP) and Shift-invariance Discrete Wavelet Transform (SiDWT) methods. Experimental results show that the developed method outperforms other traditional methods and can effectively improve the quality of the fused image. |
| Paper Nr: | 160 |
| Title: | Program-based and Model-based PLC Design Environment for Multicore FPGA Architectures |
| Authors: | Christoforos Economakos, Michael Skarpetis and George Economakos |
| Abstract: | Digital design has been growing rapidly during the last years, offering advanced implementation solutions for a diversity of appliances and instruments, integrating different sensors and actuators. This has a great impact on embedded automation, where traditional Programmable Logic Controllers (PLCs) have been gradually replaced by high performance Embedded Controllers, Digital Signal Processor (DSP) chips and, more recently, power efficient Field Programmable Gate Arrays (FPGAs). Such new implementation platforms bring together efficient design methodologies, like model-based design and high-level or C level program-based design. In their turn, new design methodologies are accompanied by new design technologies like Intellectual Property (IP) based design and High-Level Synthesis (HLS). This paper presents a design environment that utilizes program-based and model-based design, for the development of PLC applications. Specifically, a tool flow is constructed that supports either the design of new control algorithms or the translation of existing algorithms into C. Then, HLS and FPGA implementation tools are adopted, to implement the selected algorithms as multicore, embedded designs, offering performance improvements and hardware utilization efficiency. Overall, the proposed methodology and underlying tool flow support a novel high productivity prototyping platform for digital control applications, with very promising future extension capabilities. |
| Paper Nr: | 187 |
| Title: | Modelling Exitement as a Reaction to a Virtual 3D Face |
| Authors: | Egidijus Vaškevičius, Aušra Vidugirienė and Vytautas Kaminskas |
| Abstract: | This paper introduces a comparison of a linear and nonlinear one step predictive models that were used to describe the relationship between human emotional signal – excitement – as a reaction to a virtual 3D face feature – distance between eyes. An input-output model building method is proposed that allows building a stable model with the least output prediction error. Validation was performed using the recorded signals of six volunteers and the following measures: prediction error standard deviation, relative prediction error standard deviation, and average absolute relative prediction error. Validation results of the models showed that both models predict excitement signal in relatively high prediction accuracy. |
| Paper Nr: | 227 |
| Title: | New Solutions for Modeling and Verification of B-based Reconfigurable Control Systems |
| Authors: | Raja Oueslati, Olfa Mosbahi, Mohamed Khalgui and Samir Ben Ahmed |
| Abstract: | The paper deals with the modeling and verification of B method-based reconfigurable control systems. Reconfiguration means the dynamic changes of the system behavior at run-time according to well-defined conditions to adapt it to its environment. A reconfiguration scenario is applied as a response to improve the system′s performance, or also to recover and prevent hardware/software errors, or also to adapt its behavior to new requirements according to the environment evolution. A new extension called Reconfigurable B “R-B”is proposed to specify reconfigurable control systems. It consists of two modules: Behavior and Control. The first defines all possible behaviors of the system, and whereas the second is a set of reconfiguration functions applied to change the system from a behavioral configuration to another one at run-time. We verify a reconfigurable control system by using the B method. The goal is to guarantee the consistency and the correctness of the abstract specification level. The second contribution of this paper deals with the verification of the reconfigurable system by avoiding redundant checking of different behaviors sharing similar operations. In order to control the complexity of verification, an optimal algorithm is developed and a prototyped tool called “Check R-B”is implemented. The paper′s contribution is applied to a benchmark production system FESTO. |
| Paper Nr: | 245 |
| Title: | Applicability of Thermal Comfort Models to Car Cabin Environments |
| Authors: | Diana Hintea, John Kemp, James Brusey, Elena Gaura and Neil Beloe |
| Abstract: | Car cabins are non-uniform and asymmetric environments in relation to both air velocity and temperature. Estimating and controlling vehicle occupant thermal comfort is therefore a challenging task. This paper focuses on evaluating the suitability of four existing thermal comfort models, namely the Predicted Mean Vote (PMV), Taniguchi’s model, Zhang’s model and Nilsson’s model in a variety of car cabin conditions. A series of comfort trials were performed ranging from controlled indoor trials to on-road driving trials. The outputs of all four models were compared to the sensation index reported by the subjects situated in the driver seat. The results show that PMV and Nilsson’s model are generally applicable for the car cabin environment, but that they are most accurate when there is a small air temperature rate of change (of under 1.5 ºC per minute), giving correlation levels of 0.91 and 0.93 for the two models respectively. Taniguchi’s and Zhang’s models were found unsuitable for all conditions, with correlation levels ranging between 0.03 and 0.60. Nilsson’s model is recommended by the authors based on the level of agreement with the subjective reports, its ability to estimate both local and overall thermal sensation and the smaller number of input parameters. |
| Paper Nr: | 275 |
| Title: | Exploring the Use of Smartphone Accelerometer and Gyroscope to Study on the Estimation of Road Surface Roughness Condition |
| Authors: | Viengnam Douangphachanh and Hiroyuki Oneyama |
| Abstract: | Smartphones are potentially useful to be adopted as a cost-effective and easy to implement tool for the measurement of road surface roughness condition, which is very essential for road monitoring and maintenance planning. In this study, an experiment has been carried out to collect data from accelerometers and gyroscopes on smartphones, which are placed at different locations inside vehicles running on road sections with different roughness conditions. The collected data is processed in the frequency domain to calculate magnitudes of the vibration. It has been revealed that at the considered frequency range of 40-50Hz, there is a very strong relationship between road roughness condition and the magnitudes of vibration, calculated from each axis of the accelerometers and gyroscopes; as well as the average speed. Road roughness condition that is modelled as a linear function of the vibration magnitudes, taking into account of both data from accelerometer and gyroscope as well as the average speed, achieves better estimation than the model that takes into account the magnitude from the accelerometer and the average speed alone. The finding is potentially significant for the development of a more accurate model and a better smartphone app to estimate road roughness condition from smartphone sensors. |
| Paper Nr: | 276 |
| Title: | Detection of Gait Events and Assessment of Fall Risk Using Accelerometers in Assisted Gait |
| Authors: | A. Tereso, M. Martins, C. P. Santos, M. Vieira da Silva, L. Gonçalves and L. Rocha |
| Abstract: | The use of the walker in rehabilitation has increased in the past few years. Therapists evaluate patient’s rehabilitation by observation and subjective tests. Thus, it is necessary the use of an assistive tool which can measure and quantify the patient’s walker-assisted movement and stability, providing an objective clinical assessment. The aim of this study is to detect differences in assisted gait when using the assistive devices (ADs) – crutches, standard walker and rollator (4-wheeled walker) with forearm supports (RFS) - in patients with knee osteoarthritis (KOA) that suffered the surgery - Total Knee Arthroplasty (TKA). Additionally, it is to verify the link between gait parameters and acceleration signals. The evaluation is reached by the use of two 3 axis-accelerometers. The signals extracted from the sensors, at the ankle and trunk, are related to gait events and evaluation of fall risk, respectively. Results show that despite the differences between the signals obtained with the three ADs and with the subjects in this study, it is possible to identify effectively the gait parameters and prove the stability that the RFS provides. |
Posters
| Paper Nr: | 39 |
| Title: | Discrete Event System Based Pyroprocessing Modeling and Simulation |
| Authors: | Hyo Jik Lee, Won Il Ko, Sung Ki Kim, Seong Yeol Choi, Han Soo Lee, Geun Il Park and In Tae Kim |
| Abstract: | The pyroprocessing operation-modelling is characterized as complicated batch type operation and tangled material flow logic, and handling many numbers of chemical elements. Discrete event system modeling was performed to build an integrated operation model, a simulation of which showed that a dynamic material flow was implemented. All data related to a dynamic material flow were recorded in database tables, and used for verification and validation in terms of material balance. Compared to equilibrium material balance, dynamic mass balance showed that the amount of material transported upstream and downstream in the unit process satisfied the mass balance equation at every batch operation. This study also showed that a dynamic material flow, which is a basic framework for an integrated pyroprocessing simulator, was well working. The integrated model built thus far will be improved in a few years toward an integrated simulator with safeguards assessment, technical feasibility, and economic feasibility modules. |
| Paper Nr: | 40 |
| Title: | Optimization of Adaptive Up-and-Down Method for Equivalent Time Signal Conversion |
| Authors: | K. Kruminsh and V. Plocinsh |
| Abstract: | This study relates to comparator type equivalent time signal conversion. The influence of parameters of combined adaptive up-and-down method on accuracy of signal conversion is studied. Optimal values of parameters are obtained, using which the minimal amount of the samples is ensured. As an input signal, a model of UWB radar signal (sine monocycle) is used. Method is intended for application in UWB radar receivers. The design guidelines for application of the method in UWB radar receivers are outlined. |
| Paper Nr: | 51 |
| Title: | Stabilization of Certain Discrete Volterra Systems - An Algorithmic Approach |
| Authors: | Stelios Kotsios |
| Abstract: | Throughout this paper we present a stable feedback designing methodology for special non-linear discrete Volterra systems. It is based on a factorization algorithm which decomposes the original system as a composition of a d-polynomial and a linear series. Then the 00nice00 behaviour of this linear series guarantees the stability of the original non-linear system too. |
| Paper Nr: | 85 |
| Title: | EPE and Speed Adaptive Extended Kalman Filter for Vehicle Position and Attitude Estimation with Low Cost GNSS and IMU Sensors |
| Authors: | P. Balzer, T. Trautmann and O. Michler |
| Abstract: | This paper presents a novel approach for an adaptive Extended Kalman Filter (EKF), which is able to handle bad signal quality caused by shading or loss of Doppler Effect for low cost Global Navigation Satellite System (GNSS) receiver and Inertial Measurement Unit (IMU) sensors fused in a loosely coupled way. It uses the estimated position error as well as the speed to calculate the standard deviation for the measurement uncertainty matrix of the Kalman Filter. The filter is very easy to implement, because some conversions of the measurement, as well as the state variables, are made to reduce the complexity of the Jacobians, which are used in the EKF filter algorithm. The filter implementation is tested within a simulation and with real data and shows significantly better performance, compared to a standard EKF. The developed filter is running in realtime on an embedded device and is able to perform position and attitude estimation of a vehicle with low cost sensors. |
| Paper Nr: | 115 |
| Title: | Evaluation of Sensor Signal Health Using Model with Uniform Noise |
| Authors: | Lenka Pavelkova and Ladislav Jirsa |
| Abstract: | The paper proposes a method for evaluating a condition of a noisy sensor signal. The presented algorithm provides a binomial opinion on the sensor signal health including uncertainty by considering (i) user given bounds and (ii) measurement uncertainty. The obtained results can be utilised directly for a single sensor or in a hierarchical structure describing an industrial system of interest where sensors comprise one of the basic building block. There, each block provides a binomial opinion about its health including uncertainty. These opinions are combined using the rules of probabilistic logic so that a single opinion on the health of the whole monitored system is obtained. |
| Paper Nr: | 123 |
| Title: | Design of a Filter-bank by the Wave Digital Filter Technique - An approach for the Chebishev Bank-Filter by the Wave Digital Filter Technique |
| Authors: | Adan Bonilla Chavez, Bohumil Psenicka and Jiri Hospodka |
| Abstract: | This paper presents a simple procedure for design of the filter-bank with Wave digital filter (WDF). The filter-bank is constructed using Chebyshev and Inverse Chebyshev filters. Wave digital filters are derived from LC filters and consist of cascade connections of serial and parallel adapters. These adapters contains the necessary adders, multipliers and inverters. A great advantage of this procedure is that the filters in the wave digital filterbank synthesis are obtained from the wave digital filter-bank analysis only by changing some signs in the end of delay elements. |
| Paper Nr: | 129 |
| Title: | Linearizing Controller for Higher-degree Nonlinear Processes with Compensation for Modeling Inaccuracies - Practical Validation and Future Developments |
| Authors: | Pawel Nowak, Jacek Czeczot, Tomasz Klopot, Mateusz Szymura and Bogdan Gabrys |
| Abstract: | This work shows the results of the practical implementation of the linearizing controller for the example laboratory pneumatic process of the third relative degree. Controller design is based on the Lie algebra framework but in contrast to the previous attempts, the on-line model update method is suggested to ensure offset-free control. The paper details the proposed concept and reports the experiences from the practical implementation of the suggested controller. The superiority of the proposed approach over the conventional PI controller is demonstrated by experimental results. Based on the experiences and the validation results, the possibilities of the potential application of the data-driven soft sensors for further improvement of the control performance are discussed. |
| Paper Nr: | 132 |
| Title: | Speaker State Recognition with Neural Network-based Classification and Self-adaptive Heuristic Feature Selection |
| Authors: | Maxim Sidorov, Christina Brester, Eugene Semenkin and Wolfgang Minker |
| Abstract: | While the implementation of existing feature sets and methods for automatic speaker state analysis has already achieved reasonable results, there is still much to be done for further improvement. In our research, we tried to carry out speech analysis with the self-adaptive multi-objective genetic algorithm as a feature selection technique and with a neural network as a classifier. The proposed approach was evaluated using a number of multi-language speech databases (English, German and Japanese). According to the obtained results, the developed technique allows an increase in emotion recognition performance by up to 6.2% relative improvement in average F-measure, up to 112.0% for the speaker identification task and up to 6.4% for the speech-based gender recognition, having approximately half as many features. |
| Paper Nr: | 135 |
| Title: | Nonlinear Models of BPSK Costas Loop |
| Authors: | E. V. Kudryasoha, O. A. Kuznetsova, N. V. Kuznetsov, G. A. Leonov, S. M. Seledzhi, M. V. Yuldashev and R. V. Yuldashev |
| Abstract: | Rigorous nonlinear analysis of the physical model of Costas loop is very difficult task, so for analysis, simplified mathematical models and numerical simulation are widely used. In the work it is shown that the use of simplified mathematical models, and the application of non rigorous methods of analysis may lead to wrong conclusions concerning the operability of Costas loop. |
| Paper Nr: | 195 |
| Title: | Relay Based PID Auto-tuning Applied to a Multivariable Level Control System |
| Authors: | Diogo C. Nunes, Jan E. M. G. Pinto, Daniel G. V. Fonseca, André L. Maitelli and Fábio M. U. Araújo |
| Abstract: | In industrial applications involving control systems, PID controllers are present in the great majority of them, mostly because of a very simple architecture and easy tuning. For tuning them, the relay method is also very simple to use and, usually, reach some very satisfactory results, once combined with the appropriate strategy, like Ziegler-Nichols, Cohen-Coon, CHR, and others. Using this methodology, this paper presents a relay based PID auto-tuning applied to a multivariable coupled tanks system. |
| Paper Nr: | 233 |
| Title: | Flexible Shape Measurement System for Chemical Plant Using Magnetic Sensors |
| Authors: | Kumiko Yoshida and Kikuhito Kawasue |
| Abstract: | We propose a flexible computer vision system using magnetic sensors. The system enables a flexible free scanning of a CCD camera and a laser slit using 3D magnetic sensors. Many numbers of views of each model from different angles can be taken on measuring the configuration between a CCD camera and a laser slit projector simultaneously. The information of different views is combined to reconstruct the 3D object on a computer display. In this paper, the application for pipe measurement is introduced. Experimental results show the feasibility of our system. |
| Paper Nr: | 233 |
| Title: | Flexible Shape Measurement System for Chemical Plant Using Magnetic Sensors |
| Authors: | Kumiko Yoshida and Kikuhito Kawasue |
| Abstract: | We propose a flexible computer vision system using magnetic sensors. The system enables a flexible free scanning of a CCD camera and a laser slit using 3D magnetic sensors. Many numbers of views of each model from different angles can be taken on measuring the configuration between a CCD camera and a laser slit projector simultaneously. The information of different views is combined to reconstruct the 3D object on a computer display. In this paper, the application for pipe measurement is introduced. Experimental results show the feasibility of our system. |
| Paper Nr: | 238 |
| Title: | Reduced DoFs of Digital Hand Based on Anatomy for Real Time Operation |
| Authors: | Hiroshi Hashimoto, Akinori Sasaki, Koji Makino and Kaoru Mitsuhashi |
| Abstract: | This paper describes a model of using a digital hand, which mimics human hands, operates dynamically in real time operation. Focusing on real time operation, we consider a model structure of digital hand with reduced DoFs (degree of freedoms) as an approximated model, where the reduction is based on the anatomical and medical hand analysis. There some problems because of the approximated model. To overcome the problems, some techniques are implemented into the model. We examine how the model is able to mimic the movement of human hands. |
| Paper Nr: | 246 |
| Title: | WSN-based near Real-time Environmental Monitoring for Shelf Life Prediction through Data Processing to Improve Food Safety and Certification |
| Authors: | G. E. Biccario, V. F. Annese, S. Cipriani and D. De Venuto |
| Abstract: | This position paper aims to support a control technique in the perishables goods supply-chain through a combination of near real-time wireless sensor network (WSN) for environmental monitoring and further data processing to predict the shelf life of the product. This approach returns a low cost, versatile and efficient tool that can significantly improve the safety and food certification through the organoleptic qualities control using three different sensors, i.e. temperature, light and humidity. In this article, therefore, the advantages of the proposed technique are explained and a case study is presented to support this approach, as well as an example of processing algorithm for shelf life evaluation. |
| Paper Nr: | 277 |
| Title: | Improving Lidar Data Evaluation for Object Detection and Tracking Using a Priori Knowledge and Sensorfusion |
| Authors: | David Wittmann, Frederic Chucholowski and Markus Lienkamp |
| Abstract: | This paper presents a new approach to improve lidar data evaluation on the basis of using a priori knowledge. In addition to the common I- and L-shapes, the directional IS-shape, the C-shape for pedestrians and the E-shape for bicycles are introduced. Considering the expected object shape and predicted position enables effective interpretation even of poor measurement values. Therefore a classification routine is utilized to distinguish between three classes (cars, bicycles, pedestrians). The tracking operation with Kalman filters is based on class specific dynamic models. The fusion of radar objects with the used a priori knowledge improves the quality of the lidar evaluation. Experiments with real measurement data showed good results even with a single layer lidar scanner. |
| Paper Nr: | 286 |
| Title: | Adaptive LQG/LTR Control; Discontinuity Issue |
| Authors: | Dariusz Horla and Andrzej Krolikowski |
| Abstract: | An adaptive LQG control with no control cost is considered. In such case the loop transfer recovery (LTR) effect can be obtained. The control problem is handled using discrete-time state-space model and the parameter estimation is performed for corresponding ARMAX model which can be represented in innovation state-space form. Thus the direct estimation of model parameters is possible by means of standard ERLS procedure and the adaptive control is implemented through {\em certainty equivalence principle}. In such a situation the problem of solution continuity of Riccati equation can arise for nonminimum-phase systems. Computer simulations of third-order systems modeled by a second-order minimum-phase and nonminimum-phase models are given to illustrate the robustness and performance properties of the adaptive controller, particularly with respect to the modelling error parameter $\eta$. |
Area 4 - Industrial Engineering, Production and Management
Full Papers| Paper Nr: | 101 |
| Title: | 2-D Load Transfer Control Considering Obstacle Avoidance and Vibration Suppression |
| Authors: | Junichi Nakajima and Yoshiyuki Noda |
| Abstract: | This paper is concerned with an advanced transfer control for load transfer machines such as a crane. In the load transfer machine, it is required to carry the load efficiently and safety. In order to satisfy this requirement, fast transfer of load, obstacle avoidance and vibration suppression have to be accomplished in the load transfer system. Therefore in this study, the load transfer control system which the transfer trajectory on a plane is optimized in consideration of the vibration suppression, obstacles avoidance and fast transfer is proposed. Moreover, in order to optimize the trajectory in a short time, the fast solution approach is also proposed in this study. The effectiveness of the proposed transfer control system is verified by the experiments using the laboratory type overhead traveling crane system. |
| Paper Nr: | 148 |
| Title: | Process Characterization and Evaluation of NC Machining Processes based on Macroscopic Engagement Simulation |
| Authors: | Meysam Minoufekr, Pascal Schug and Mihir Joshi |
| Abstract: | With a view to achieve stable production, nowadays the process design and planning goes through a time and resource intensive correction loop. The process output after machining trials is used to determine the critical process sections, and hence the experience of the process designer is decisive in the productivity of the optimization loop and the process. The implementation of a machining simulation can enhance the productivity of the process design and planning phase. The macroscopic engagement simulation provides an efficient tool for process evaluation. Moreover, it provides a basis for derivation of microscopic geometric process parameters, which have a direct correlation to mechanical and thermal loads. Thus, detailed information relating to the cutting loads on the tool is derivable at every point on the toolpath, enabling analysis of NC machining process based purely on the macroscopic geometric engagement between the cutting tool and workpiece. This information regarding the engagement conditions can be used to proactively identify potential critical process sections in a virtual environment thereby increasing the process reliability. Thus a process design for an optimal tool load is possible resulting in improved tool life, process efficiency and reduction in utilised resources. |
Short Papers
| Paper Nr: | 49 |
| Title: | Electric Utility Enterprise Architecture to Support the Smart Grid - Enterprise Architecture for the Smart Grid |
| Authors: | I. Parra, A. Rodríguez and G. Arroyo-Figueroa |
| Abstract: | Smart grid is the new tendency for the Electric Public Utilities. The Smart Grid concept means the total automation for all processes of the EPU. For implement Smart Grid in an EPU are necessary to define enterprise architecture. The enterprise architecture to meet Smart Grid requirements for management systems for EPU in México is presented in this paper. The architecture shows layers of abstraction in the main process: generation, transmission, distribution and energy control and includes automation and control systems at all levels, from plants and substations control systems to corporative intelligent centre, including the operating centre and the energy trading system. Some results and experiences are discussed. |
| Paper Nr: | 88 |
| Title: | An Automated Work Cycle Classification and Disturbance Detection Tool for Assembly Line Work Stations |
| Authors: | Karel Bauters, Hendrik Van Landeghem, Maarten Slembrouck, Dimitri Van Cauwelaert and Dirk Van Haerenborgh |
| Abstract: | The trend towards mass customization has led to a significant increase of the complexity of manufacturing systems. Models to evaluate the complexity have been developed, but the complexity analysis of work stations is still done manually. This paper describes an automated analysis tool that makes us of multi-camera video images to support the complexity analysis of assembly line work stations. |
| Paper Nr: | 89 |
| Title: | Design and Development of an Energy Efficiency Knowledge Center (EEKC) |
| Authors: | Bhaskaran Gopalakrishnan, Mohammad S. Jalali, Subodh Chaudhari, Deepak Gupta and Ed Crowe |
| Abstract: | Over the last two decades, the Industrial Assessment Center (IAC) at West Virginia University has worked with more than 500 small and medium sized manufacturing companies to identify energy and productivity saving opportunities. The savings, which keep adding up year after year, are appreciable but do not fully capture the potential impacts of the IAC Program. On average, the implementation rate of the recommendations has been only about 40%. This rate was expected to improve with the use of a knowledge center. Energy Efficiency Knowledge Center (EEKC) is a regional system which includes the development and deployment of technical resources to assist industrial facilities in energy assessment phases. It supports continuous improvement by incorporating the knowledge of IAC experts and the plant personnel. The EEKC provides information to clients on how to obtain baseline energy use for their specific energy systems using tools such as Quick Plant Energy Profiler (Quick PEP) by the US Department of Energy (DOE). It helps users to evaluate the energy efficiency measures during the pre-assessment and assessment phases. In this research, the IAC activities and tasks are studied and the steps to develop an online knowledge center are reviewed. |
| Paper Nr: | 92 |
| Title: | Material Handling, Inventory and Productivity Improvement - A Lean Six Sigma Approach Case Study |
| Authors: | Wa-Muzemba Anselm Tshibangu |
| Abstract: | This paper describes a two-step strategic-tactical Lean Six Sigma methodology as used by the author to improve productivity, enhance inventory and material handling management, and thus, reduce operational costs at “Down Town Press Inc.”, a commercial printing press located in New York State, USA. A close look at the company’s performance revealed a troubling picture with only 51 % utilization of personnel, nearly $40,000 of invested capital underutilized annually, and an excess of monthly inventory costs of almost $29,000. This study was conducted to help the company avoid a fatal bankruptcy and regain financial prosperity. First, a strategic Six Sigma DMAIC procedure approach is deployed to better understand the deep turmoil faced by Down Town Press Inc. Second, a more tactical Lean approach is applied to identify various wastes and propose a set of techniques, technologies and strategies to reduce or eliminate the identified wastes, and thus, reduce operational costs. The continuous improvement changes proposed at the conclusion of the study suggest a possible reduction of $300,000 in yearly operational capital. Furthermore, with the implementation of the proposed Inventory Management integrated with a comprehensive Material Handling Management System, the study predicts a higher utilization of employees and, therefore, an increased productivity. |
| Paper Nr: | 149 |
| Title: | A Petri Net Model for an Open Path Multi-AGV System |
| Authors: | Davide Giglio |
| Abstract: | Automated distribution warehouses in which pallet and roll pallet loads are transported by means of forklift AGVs are considered in this work, with the objective of defining a mathematical model which accurately represents the behaviour of AGVs in the system. AGVs can move freely in the warehouse (an open path AGV system is adopted), and their transportation activities can be modelled as a sequence of elementary or basic actions. In the paper, a coloured Petri net (CPN) model is proposed. It allows representing any sequence of elementary actions of AGVs (including pick-up and drop-off activities), and accurately models the interactions among AGVs, in order to guarantee the safety during the execution of activities. The CPN model can be used to analyse and implement deadlock prevention and deadlock recovery strategies, and it has been adopted in the building of a discrete-event simulator which is employed to analyse the system’s performance and to evaluate scheduling policies for transportation tasks. |
| Paper Nr: | 278 |
| Title: | A Mixed-Integer Mathematical Programming Model for Integrated Planning of Manufacturing and Remanufacturing Activities |
| Authors: | Davide Giglio and Massimo Paolucci |
| Abstract: | This paper considers a hybrid remanufacturing and manufacturing system on a closed-loop supply chain. The system manufactures a set of new products characterized by a multi-level structure through multi-stage assembly operations. The required raw or basic parts can be acquired new from suppliers or provided as new by a de-manufacturing facility which performs a remanufacturing process from acquired old products returned by customers. The quality of returned products has impact on the quantity of recovered basic parts which can be assumed as good as new, and on the duration of the remanufacturing process. The considered problem is to determine the production lots for the system machines as well as the quantity of new basic parts and retuned products to be acquired in order to satisfy a deterministic demand in the time buckets of the planning period. The performance criterion to be minimized includes the acquisition costs for the new and returned items, inventory and production costs, recovering and disposal costs, and tardiness costs. A mixed-integer programming model is proposed and its effectiveness is demonstrated by experiments on a case study. |
Posters
| Paper Nr: | 56 |
| Title: | The Effect of Tactical Situation Display on Attack Helicopter Pilot’s Workload |
| Authors: | Eunghyun Lee and Yongjin Kwon |
| Abstract: | The attack helicopter performs numerous tasks, such as anti-armor operation, close air support, search and destroy, and reconnaissance. As 71% of aviation accidents are human-caused, high workload and stress level of pilots greatly affect their performance level. Additionally, pilots that are responsible for attack helicopters have to work under enemy threats, which increase their stress levels. In order to decrease their workload, we installed a TSD (Tactical Situation Display) in our helicopter simulator. Then, we analysed the results to find out if the TSD affects the work efficiency and mental pressure of the pilots. We analysed the task performance time and the pilot workload using the NASA-TLX with the paired sample method. The test indicates that the additional information provided by the TSD can help reduce the pilot workload. |
| Paper Nr: | 100 |
| Title: | Decentralized Diagnosis and Diagnosability of a Class of Hybrid Dynamic Systems |
| Authors: | Louajri H. and Sayed-Mouchaweh M. |
| Abstract: | In this paper, an approach for fault diagnosis of hybrid dynamic systems (HDS), in particular discretely controlled continuous system, is proposed. The goal is to construct a decentralized diagnosis structure, able to diagnose parametric and discrete faults. This approach considers the system as composed of a set of interacted hybrid components (HCs). Each HC is composed of a discrete component (Dc), e.g. on/off switches, with the continuous components (Ccs), e.g. capacitors, whose continuous dynamic behaviour is influenced by the Dc discrete states. A local hybrid diagnosis module, called diagnoser, is associated to each HC in order to diagnose the faults occurring in this HC. In order to take into account the interactions between the different HCs, local diagnosis decisions are merged using a coordinator. The latter issues a final decision about the origin of the fault and identifies its parameters. The advantage of the proposed approach is that local hybrid diagnosers as well as the coordinator are built using local models. |
| Paper Nr: | 121 |
| Title: | 3D Simulation of Industrial Large-scale Ceramics Furnace in SIMIO Platform Environment |
| Authors: | Georgios Tsaousoglou and Stamatis Manesis |
| Abstract: | This article presents a 3D simulation of an industrial large-scale furnace operating in the NGC (Northern Greece Ceramics) ceramics industrial plant. The 3D modelling and simulation of the long industrial furnace is based on the SIMIO software platform the capabilities of which are explored and tested in such a complex production plant. After the understanding of the real system operational characteristics, its macroscopic behaviour has been extracted and modelled; then a 3D model was created. Using the model, matters concerning the production process optimization are explored, while also alternative production scenarios are simulated, so that conclusions for the system’s behaviour at value variation of the functional parameters of the real system can be extracted, without experimenting on the real process. In the four main sections of this article, the following aspects are presented: the modeling approach of the furnace operation, the SIMIO model of the furnace, its operation, examples of possible model applications and utility of the developed model and further modeling of the whole production procedure preceding the furnace. |
| Paper Nr: | 147 |
| Title: | Designing CAx-process Chains - Model and Modeling Language for CAx-Process Chain Methodology |
| Authors: | Pascal Schug and Alexandr Kotlov |
| Abstract: | Product development and production processes are supported by software systems during the development and planning phases. The usage of these software tools during or prior to and post the different process steps is called CAx-processes. The combination of these CAx-processes form process chains, also known as CAx-process chains (CAx-PCs), which mirror the production processes virtually. The content of this paper introduces a solution for designing the software chains in conformity to the methodology for evaluation, analysis and optimization of CAx-PCs. The solution includes the definition of DSL expressing the model for CAx-PCs and the software prototype "CAx-process chain designer" for deriving the alternatives of CAx-PCs from the expressed model. |
| Paper Nr: | 216 |
| Title: | A Modified Preventive Maintenance Model with Degradation Rate Reduction in a Finite Time Span |
| Authors: | Chun-Yuan Cheng, Jr-Tzung Chen, Te-Hsiu Sun and Mei-Ling Liu |
| Abstract: | Preventive maintenance (PM) can slow the deterioration process of a repairable system and restore the system to a younger state. The proposed PM model of this paper focuses on the restoration effect of degradation rate reduction which can only relieve stress temporarily and slow the rate of system degradation while the hazard rate is still monotonically increased. This PM model considers a deteriorating but repairable system (or equipment) with a finite life time period. This PM model is modified based on an original degradation-rate-reduction PM model over a finite time span of which the searching range for the optimal solution of the time interval between each PM is limited. It is demonstrated that the proposed degradation-rate-reduction PM model over a finite time period can have a better optimal solution than the original PM model. The algorithm of finding the optimal solution for the modified PM model is developed. Examples are provided and are compared with the corresponding original PM model. |