Title: |
USEFUL COMPUTER VISION TECHNIQUES FOR A ROBOTIC
HEAD |
Author(s): |
O. Deniz, M. Castrillon, J. Lorenzo and L. A.
Canalis |
Abstract: |
This paper describes some simple but useful computer
vision techniques for human-robot interaction. First, an omnidirectional
camera setting is described that can detect people in the surroundings of
the robot, giving their angular positions and a rough estimate of the
distance. The device can be easily built with inexpensive components.
Second, we comment on a color-based face detection technique that can
alleviate skin-color false positives. Third, a person tracking and
recognition system is described. Finally, a simple head nod and shake
detector is described, suitable for detecting affirmative/negative,
approval/disapproval, understanding/disbelief head gestures. |
|
Title: |
FUZZY-SYNTACTIC APPROACH TO PATTERN RECOGNITION AND
SCENE ANALYSIS |
Author(s): |
Marzena Bielecka, Marek Skomorowski and Andrzej
Bielecki |
Abstract: |
In syntactic pattern recognition an object is described
by symbolic data. The problem of recognition is to determine whether the
describing mathematical structure, for instance a graph, belongs to the
language generated by a grammar describing the mentioned mathematical
structures. So called ETPL(k) graph grammars are a known class of grammars
used in pattern recognition. The approach in which ETPL(k) grammars are
used was generalized by using probabilistic mechanisms in order to apply
the method to recognize distorted patterns. In this paper the next step of
the method generalization is proposed. The ETPL(k) grammars are improved
by fuzzy sets theory. It turns out that the mentioned probabilistic
approach can be regarded as a special case of the proposed one.
Applications to robotics are considered as well. |
|
Title: |
TASK PLANNER FOR HUMAN-ROBOT INTERACTION INSIDE A
COOPERATIVE DISASSEMBLY ROBOTIC SYSTEM |
Author(s): |
Carolina Díaz, Santiago Puente and Fernando
Torres |
Abstract: |
This paper develops a task planner that allows
including a human operator which works cooperatively with robots inside an
automatic disassembling cell. This method gives the necessary information
to the system and the steps to be followed by the manipulator and the
human, in order to obtain an optimal disassembly and a free-shock task
assignation that guarantees the safety of the human operator. |
|
Title: |
A SET APPROACH TO THE SIMULTANEOUS LOCALIZATION AND MAP
BUILDING - Application to Underwater Robots |
Author(s): |
Luc Jaulin, Frédéric Dabe, Alain Bertholom and Michel
Legris |
Abstract: |
This paper proposes a set approach for the simultaneous
localization and mapping (SLAM) in a submarine context. It shows that this
problem can be cast into a constraint satisfaction problem which can be
solve efficiently using interval analysis and propagation algorithms. The
efficiency of the resulting propagation method is illustrated on the
localization of submarine robot, named Redermor. The experiments have been
collected by the GESMA (Groupe d'Etude Sous-Marine de l'Atlantique) in the
Douarnenez Bay, in Brittany. |
|
Title: |
ROBUST AND ACTIVE TRAJECTORY TRACKING FOR AN AUTONOMOUS
HELICOPTER UNDER WIND GUST |
Author(s): |
Adnan Martini, François Léonard and Gabriel
Abba |
Abstract: |
The helicopter manoeuvres naturally in an environment
where the execution of the task can easily be affected by atmospheric
turbulences, which lead to variations of its model parameters. Here, a
nonlinear simple model with 3-DOF of a helicopter with unknown
disturbances is used. Two approaches of robust control are compared via
simulations: a nonlinear feedback and an active disturbance rejection
control based on a nonlinear extended state observer(ADRC). |
|
Title: |
A NEWMARK FMD SUB-CYCING ALGORITHM |
Author(s): |
J. C. Miao, P. Zhu, G. L. Shi and G. L.
Chen |
Abstract: |
The sub-cycling algorithm, which was firstly presented
by Belytschko T. et al [5], have been successfully applied in structural
dynamical FEM analysis. However, sub-cycling algorithms, which can be used
for the flexible multi-body systems (FMS), are still not presented up to
now. This paper presents a Newmark method based sub-cycling algorithm,
which is suitable for solving the condensed flexible multi-body dynamic
(FMD) equations. Common-step update formations and sub-step update
formations for quickly changing variables and slowly changing variables of
the FMD formations are established based on the original differential
equations. Stability of the sub-cycling procedure is checked by means of
energy balance checking during the integral process. Numerical examples
indicate that the sub-cycling algorithm is able to enhance the
computational efficiency without dropping results accuracy
greatly. |
|
Title: |
RPQ: ROBOTIC PROXIMITY QUERIES - Development and
Applications |
Author(s): |
Albert Hernansanz, Xavier Giralt, Alberto Rodriguez and
Josep Amat |
Abstract: |
This paper presents a robotic proximity query package
(RPQ) as an optimization of the general collision library PQP (Proximity
Query Package) for the detection of collisions and distance computation
between open kinematic chains such as robotic arms. The performance of the
optimizations to non specific collision query packages are explained and
evaluated. Finally, a robotic assisted surgical application is presented
which has been used as a test bed for the proximity package. |
|
Title: |
ESTIMATION OF CAMERA 3D-POSITION TO MINIMIZE
OCCLUSIONS |
Author(s): |
Pablo Gil, Fernando Torres and Oscar
Reinoso |
Abstract: |
Occlusions are almost always seen as undesirable
singularities that pose difficult challenges to recognition processes of
objects which have to be manipulated by a robot. Often, the occlusions are
perceived because the point of view with which a scene is observed is not
adapted. In this paper, a strategy to determine the location, orientation
and position, more suitable so that a camera has the best point of view to
capture a scene composed by several objects is presented. The estimation
for the best location of the camera is based on minimizing the zones of
occlusion by the analysis of a virtual image sequence in which is
represented the virtual projection of the objects. These virtual
projections represent the images as if they were captured by a camera with
different view points without moving it |
|
Title: |
WEB-BASED INTERACTIVE POSITIONING CONTROL OF AN
ELECTRIC FLATCAR VIA WIRELESS NETWORK |
Author(s): |
Ken Ishii, Koki Abe and Yoshimi Takao |
Abstract: |
A large tank has been used for target strength pattern
measurements of fish. It is equipped with an electric flatcar. Further an
elevation-rotating unit runs on the rails above it. The probe on the top
of its elevation unit is equipped with an attachment for an ultrasonic
transducer. The manipulator probe is movable in the four directions of the
x, y, z and rotation axes. Installation of a remote control switch has
been required for the purpose of efficient operation of an electric
flatcar. A remote control system using a notebook personal computer has
been developed with good cost performance. The PC is equipped with a
wireless network interface card. A model of WEB direct-access monitoring
has been designed newly on the basis of the concept that an operator can
control a mechanical device using a WEB Browser via LAN. Furthermore it
performs double exclusive control for access from multi PCs, and has made
possible a controller and multiple-monitor system. The mission was
performed for the purpose of evaluation of WEB operation. The result has
made clear the specifications for motion, and an external interface of the
electric flatcar is applicable to the new protocol developed for WEB
Browser control. |
|
Title: |
ADAPTIVE CONTROL BY NEURO-FUZZY SYSTEM OF AN
OMNI-DIRECTIONAL WHEELCHAIR USING A TOUCH PANEL AS HUMAN-FRIENDLY
INTERFACE |
Author(s): |
Kazuhiko Terashima, Yoshiyuki Noda, Juan Urbano, Sou
Kitamura, Takanori Miyoshi and Hideo Kitagawa |
Abstract: |
For improving the operability of an omni-directional
wheelchair provided with a power assist system, the system must be able to
adapt to the individual characteristics of the many different attendants
that will use it. For achieving this purpose, an innovative
human-interface using a touch panel that provides easy input and feedback
information in real time of the operation of a power-assisted wheelchair
was developed. The system was tested experimentally with many different
attendants and the results show that in addition to providing a human
friendly interface by using the touch panel system with monitor it can
adapt successfully to the particular habits of the attendants. |
|
Title: |
NAVIGATION SYSTEM FOR INDOOR MOBILE ROBOTS BASED ON
RFID TAGS |
Author(s): |
Toshifumi Tsukiyama and Atsushi Suzuki |
Abstract: |
A new navigation method is described for an indoor
mobile robot. The robot system is composed of a Radio Frequency
Identification (RFID) tag sensor and a commercial three-wheel mobile
platform with ultrasonic rangefinders. The RFID tags are used as landmarks
for navigation and the topological relation map which shows the connection
of scattered tags through the environment is used as course instructions
to a goal. The robot automatically follows paths using the ultrasonic
rangefinders until a tag is found and then refers the next movement to the
topological map for a decision. Our proposed technique would be useful for
real-world robotic applications such as intelligent navigation for
motorized wheelchairs. |
|
Title: |
IMPROVEMENT OF THE VISUAL SERVOING TASK WITH A NEW
TRAJECTORY PREDICTOR - The Fuzzy Kalman Filter |
Author(s): |
C. Pérez, N. García, J. M. Sabater, J. M. Azorín, O.
Reinoso and L. Gracia |
Abstract: |
Visual Servoing is an important issue in robotic vision
but one of the main problems is to cope with the delay introduced by
acquisition and image processing. This delay is the reason for the limited
velocity and acceleration of tracking systems. The use of predictive
techniques is one of the solutions to solve this problem. In this paper,
we present a Fuzzy predictor. This predictor decreases the tracking error
compared with the classic Kalman filter (KF) for abrupt changes of
direction and can be used for an unknown object's dynamics. The Fuzzy
predictor proposed in this work is based on several cases of the Kalman
filtering, therefore, we have named it: Fuzzy Kalman Filter (FKF). The
robustness and feasibility of the proposed algorithm is validated by a
great number of experiments and is compared with other robust
methods. |
|
Title: |
EVOLUTIONARY PATH PLANNING FOR UNMANNED AERIAL VEHICLES
COOPERATION |
Author(s): |
Ioannis K. Nikolos and Nikos Tsourveloudis |
Abstract: |
We suggest an evolutionary based off-line/on-line path
planner for cooperating Unmanned Aerial Vehicles (UAVs) that takes into
account the environment characteristics and the flight envelope and
mission constraints of the cooperating UAVs. The scenario under
consideration is the following: a number of UAVs are launched from the
same or different known initial locations. The main issue is to produce
3-D trajectories that ensure a collision free operation with respect to
mission constraints. The path planner produces curved routes that are
represented by 3-D B-Spline curves. Two types of planner are discussed:
The off-line planner generates collision free paths in environments with
known characteristics and flight restrictions. The on-line planner, which
is based on the off-line one, generates collision free paths in unknown
static environments, by using acquired information from the UAV’s on-board
sensors. This information is exchanged between the cooperating UAVs in
order to maximize the knowledge of the environment. Both off-line and
on-line path planning problems are formulated as optimization problems,
with a Differential Evolution algorithm to serve as the
optimizer. |
|
Title: |
VISUAL ALIGNMENT ROBOT SYSTEM: KINEMATICS, PATTERN
RECOGNITION, AND CONTROL |
Author(s): |
SangJoo Kwon and Chansik Park |
Abstract: |
The visual alignment robot system for display and
semiconductor fabrication process largely consists of multi-axes precision
stage and vision peripherals. One of the central issues in a display or
semiconductor mass production line is how to reduce the overall tact time
by making a progress in the alignment technology between mask and panel.
In this paper, we suggest the kinematics of the 4PPR parallel alignment
mechanism with four limbs unlike usual three limbs cases and an effective
pattern recognition algorithm for alignment mark recognition. The inverse
kinematic solution determines the moving distances of joint actuators for
an identified mask-panel misalignment. Also, the proposed alignment mark
detection method enables considerable reduction in computation time
comparing with well-known pattern matching algorithms. |
|
Title: |
INTEGRATED DESIGN OF A MECHATRONIC SYSTEM - The
Pressure Control in Common Rails |
Author(s): |
Paolo Lino and Bruno Maione |
Abstract: |
This paper describes the integrated design of the
pressure control in a common-rail injection system. Mechanical elements
and the embedded controller are considered as a whole, using a
multi-disciplinary approach to modelling and simulation. The virtual
prototype, which provides the detailed geometrical/physical model of the
mechanical parts, plays the role of a surrogate of a reference hardware
prototype in reduced-order modelling, validation, and/or in tuning the
control parameters. The results obtained by the proposed approach are
compared and validated by experiments. |
|
Title: |
ULTRA VIOLET IMAGING TRANSDUCER CONTROL OF A THERMAL
SPRAYING ROBOT |
Author(s): |
D. Breen, E. Coyle and D. M. Kennedy |
Abstract: |
The thermal spraying industry has a global market of
$1.3 billion. This industry relies heavily on manual operation of the
thermal spraying equipment or in some cases, robotic systems that require
costly set up of material for surface coating and time consuming
trajectory planning. The main objective of this research was to
investigate novel ideas for automating the thermal spraying process. This
requires transducers that can provide information about arbitrarily shaped
and orientated material for spraying and generating the trajectory plan
for the robot manipulator during the thermal spraying process in real
time. The most significant difficulty for any transducer, particularly low
cost vision systems is the thermal spraying process which in our research
is molten material such as aluminium in an Oxy-Acetylene flame with
temperatures exceeding 31000C. This paper outlines the concept and based
on the experimental results presented demonstrates combined optical and
image processing techniques for obtaining information about objects behind
a butane flame. |
|
Title: |
ON COMPUTING MULTI-FINGER FORCE-CLOSURE GRASPS OF 2D
OBJECTS |
Author(s): |
Belkacem Bounab, Daniel Sidobre and Abdelouhab
Zaatri |
Abstract: |
In this paper, we present a new necessary and
sufficient force-closure condition for multi-finger two-dimensional (2D)
grasps. Assuming hard-finger point contact under Coulomb friction model,
we develop a new algorithm for computing force-closure grasps of 2D
objects using multifingred hand. Based on the central axis theory, an
easily computable algorithm for force-closure grasps has been implemented
and its efficiency has been demonstrated by examples. |
|
Title: |
FAST COMPUTATION OF ENTROPIES AND MUTUAL INFORMATION
FOR MULTISPECTRAL IMAGES |
Author(s): |
Sié Ouattara, Alain Clément and François
Chapeau-Blondeau |
Abstract: |
This paper describes the fast computation, and some
applications, of entropies and mutual information for color and
multispectral images. It is based on the compact coding and fast
processing of multidimensional histograms for digital images. |
|
Title: |
COMPARISON OF TWO IDENTIFICATION TECHNIQUES: THEORY AND
APPLICATION |
Author(s): |
Pierre-Olivier Vandanjon, Alexandre Janot, Maxime
Gautier and Flavia Khatounian |
Abstract: |
Parametric identification requires a well know-how and
an accurate analysis. The most popular methods consist in using simply the
least squares techniques because of their simplicity. However, these
techniques are not intrinsically robust. An alternative consists in
helping them with an appropriate data treatment. Another choice consists
in applying a robust identification method. This paper focuses on a
comparison of two techniques: a “helped” least squares technique and a
robust method called “the simple refined instrumental variable method”.
These methods will be applied to a single degree of freedom haptic
interface. |
|
Title: |
VEHICULAR ELECTRONIC DEVICES CONNECTED BY ONBOARD
FIELDBUS TECHNOLOGIES |
Author(s): |
Miguel A. Domínguez, Perfecto Mariño, Francisco Poza
and Santiago Otero |
Abstract: |
The electrical circuits and their Electronic Control
Units (ECUs) in buses and coaches are essential for their good working.
Drive, braking, suspension, opening door, security and communication
devices must be integrated in a reliable and real time information system.
The industrial communication networks or fieldbuses are a good solution to
implement networked control systems for the onboard electronics in the
public transport buses and coaches. The authors are working in the design
of multiplexed solutions based on fieldbuses to integrate the body and
chassis functions of city public transport buses. An example for the EURO5
model of the Scania manufacturer is reported in this paper. The authors
are also working in the implementation of new modules based on FPGAs
(Field Programmable Gate Arrays) that can be used in these networked
control systems. |
|
Title: |
SELECTIVE IMAGE DIFFUSION FOR ORIENTED PATTERN
EXTRACTION |
Author(s): |
A. Histace, V. Courboulay and M. Ménard |
Abstract: |
In this short paper, we present an oriented pattern
extraction method for image processing. This method is based on the use of
a particular Partial Differential Equation (PDE), issued from information
theory, which makes it possible the integration, within the diffusion
process, of prior knowledge on the data to extract. We show, as a proof of
feasibility, that this method makes it possible the integration of
selectiveness during the restoration process. This method may nd
applicability in industrial quality checks or vision in robotics for
example. |
|
Title: |
ESTIMATION OF STATE AND PARAMETERS OF TRAFFIC
SYSTEM |
Author(s): |
Pavla Pecherková, Jitka Homolová and Jindrich
Duník |
Abstract: |
This paper deals with the problem of modelling and
estimation of traffic model state and parameters for old urban areas. The
most important properties of the traffic system are described. Then the
model of the traffic system is recalled. The weakness of the model is
pointed out and subsequently rectified. Various estimation and
identification techniques, used in the traffic problem, are introduced.
The performance of various filters is validated, using the derived model
and synthetic and real data coming from the centre of Prague, with respect
to filter accuracy and complexity. |
|
Title: |
ADDRESSING COMPLEXITY ISSUES IN A REAL-TIME PARTICLE
FILTER FOR ROBOT LOCALIZATION |
Author(s): |
Dario Lodi Rizzini, Francesco Monica, Stefano Caselli
and Monica Reggiani |
Abstract: |
Exploiting a particle filter for robot localization
requires expensive filter computations to be performed at the rate of
incoming sensor data. These high computational requirements prevent
exploitation of advanced localization techniques in many robot navigation
settings. The Real-Time Particle Filter (RTPF) provides a tradeoff between
sensor management and filter performance by adopting a mixture
representation for the set of samples. In this paper, we propose two main
improvements in the design of a RTPF for robot localization. First, we
describe a novel solution for computing mixture parameters relying on the
notion of effective sample size. Second, we illustrate a library for RTPF
design based on generic programming and providing both flexibility in the
customization of RTPF modules and efficiency in filter computation. In the
paper, we also report results comparing the localization performance of
the proposed extension and of the original RTPF algorithm. |
|
Title: |
PC-SLIDING FOR VEHICLES PATH PLANNING AND CONTROL -
Design and Evaluation of Robustness to Parameters Change and Measurement
Uncertainty |
Author(s): |
Mariolino De Cecco, Enrico Bertolazzi, Giordano Miori,
Roberto Oboe and Luca Baglivo |
Abstract: |
A novel technique called PC-Sliding for path planning
and control of non-holonomic vehicles is presented and its performances
analysed in terms of robustness. The path following is based upon a
polynomial curvature planning and a control strategy that replans
iteratively to force the vehicle to correct for deviations while sliding
over the desired path. Advantages of the proposed method are its logical
simplicity, compatibility with respect to kinematics and partially to
dynamics. Chained form transformations are not involved. Resulting
trajectories are convenient to manipulate and execute in vehicle
controllers while computed with a straightforward numerical procedure in
real-time. The performances of the method that embody a planner, a
controller and a sensor fusion strategy is verified by Monte Carlo method
to assess its robustness to parameters changes and measurement
uncertainties. |
|
Title: |
PROPERTY SERVICE ARCHITECTURE FOR DISTRIBUTED ROBOTIC
AND SENSOR SYSTEMS |
Author(s): |
Antti Tikanmäki and Juha Röning |
Abstract: |
This paper presents a general architecture for creating
complex distributed software systems, called Property Service
architecture. The system may contain resources like robots, sensors, and
different kinds of system services, such as controller units, data
storages, or a collective model of the environment. This architecture
contains several solutions and distributed system design methods for
developing advanced and complex systems. It also provides the possibility
to add new resources to the system easily and during operation. Each
service has a very simple generalized interface. This meets the
requirements of distributed robotic applications, such as remote
operation, multi-robot cooperation, and the robot’s internal operation.
The simplicity of the interface also provides a possibility to scale down
the service even on the low-cost, low-performance microcontrollers used in
small-sized robots. The main features of the architecture are the dynamic
properties of the resources, automatic reconfiguration, and the high level
of reusability of the implemented methods and algorithms. |
|
Title: |
DEVELOPMENT OF THE CONNECTED CRAWLER ROBOT FOR ROUGH
TERRAIN - Realization of the Autonomous Motions |
Author(s): |
Sho Yokota, Yasuhiro Ohyama, Hiroshi Hashimoto, Jin-Hua
She, Kuniaki Kawabata, Pierre Blazevic and Hisato Kobayashi |
Abstract: |
The purpose of this paper is to develop the mobile
system for rough terrain. Our mobile system adopts the connected crawler
mechanism. This mechanism had 3 connected stages with the motor-driven
crawler tracks on each side. RC-servo motors were used for driving joints
between the stages. This system also have a high mobility on rough
terrain. In this paper, we show the mechanical features, and propose the
operation strategies for autonomous motions. We have also made
verification experiment of proposed operation strategies. For this
verification, we prepared 2 kinds of experiment. One was that the robot
passes over the different heihgt of bumps. The other was stairs ascending.
Both experiments had a great success. There were remarkable points in
these experiments. These experiment showed that the robot can pass over
the different height and different structures obstacles by using only
(same) strategies. Moreover the sensors which realize proposed strategies
was very simple, and the number of sensor was very small. Therefore it can
be concluded that proposed strategies has extremely high usefulness. |
|
Title: |
ESTIMATION PROCESS FOR TIRE-ROAD FORCES AND VEHICLE
SIDESLIP ANGLE |
Author(s): |
Guillaume Baffet, Ali Charara and Daniel
Lechner |
Abstract: |
This study focuses on the estimation of car dynamic
variables for the improvement of vehicle safety, handling characteristics
and comfort. More specifically, a new estimation process is proposed to
estimate longitudinal/lateral tire-road forces, velocity, sideslip angle
and wheel cornering stiffness. This method uses measurements from
currently-available standard sensors (yaw rate, longitudinal/lateral
accelerations, steering angle and angular wheel velocities). The
estimation process is separated into two blocks: the first block contains
an observer whose principal role is to calculate tire-road forces without
a descriptive force model, while in the second block an observer estimates
sideslip angle and cornering stiffness with an adaptive tire-force model.
The different observers are based on an Extended Kalman Filter (EKF). The
estimation process is applied and compared to real experimental data,
notably sideslip angle and wheel force measurements. Experimental results
show the accuracy and potential of the estimation process. |
|
Title: |
APPLICATION OF A HUMAN FACTOR GUIDELINE TO SUPERVISORY
CONTROL INTERFACE IMPROVEMENT |
Author(s): |
Pere Ponsa, Ramon Vilanova, Marta Díaz and Anton
Gomà |
Abstract: |
In tasks of human supervision in industrial control
room they are applied generic disciplines as the software engineering for
the design of the computing interface and the human factors for the design
of the control room layout. From the point of view of the human computer
interaction, to these disciplines it is necessary to add the usability
engineering and the cognitive ergonomics since they contribute rules for
the user centered design. The main goal of this work is the application of
a human factors guideline for supervisory control interface design in
order to improve the efficiency of the human machine systems in
automation. This communication presents the work developed to improve the
Sports Service Area interface of the Universitat Autónoma de Barcelona. |
|
Title: |
SEGMENTATION OF SATELLITE IMAGES IN OPTOELECTRONIC
SYSTEM |
Author(s): |
Andrey S. Ostrovsky, Ernesto Pino-Mota and Paulo C.
Romero-Soría |
Abstract: |
The problem of segmenting the satellite images into
homogeneous texture regions that correspond to the different classes of
terrestrial surface is considered. It is shown that this problem may be
successfully solved by using the method of spectral synthetic discriminant
functions recently proposed by the authors for classification of random
image fields and realized by means of a rather simple optoelectronic
technique. The experimental results of segmenting the true satellite
images are given. |
|
Title: |
COMPARING COMBINATIONS OF FEATURE REGIONS FOR PANORAMIC
VSLAM |
Author(s): |
Arnau Ramisa, Ramón López de Mántaras, David Aldavert
and Ricardo Toledo |
Abstract: |
Invariant (or covariant) image feature region detectors
and descriptors are useful in visual robot navigation because they provide
a fast and reliable way to extract relevant and discriminative information
from an image and, at the same time, avoid the problems of changes in
illumination or in point of view. Furthermore, complementary types of
image features can be used simultaneously to extract even more
information. However, this advantage always entails the cost of more
processing time and sometimes, if not used wisely, the performance can be
even worse. In this paper we present the results of a comparison between
some of these combinations. The test performed consists in computing the
essential matrix between panoramic images using correspondences
established with these methods. Different combinations of region detectors
and descriptors are evaluated and validated using ground truth data. The
results will help us to find the best combination to use it in a robot
navigation system. |
|
Title: |
TRAJECTORY PLANNING USING OSCILLATORY CHIRP FUNCTIONS
APPLIED TO BIPEDAL LOCOMOTION |
Author(s): |
Fernando Juan Berenguer Císcar and Félix
Monasterio-Huelin Maciá |
Abstract: |
This work presents a method for planning sinusoidal
trajectories for an actuated joint, so that the oscillation frequency
follows linear profiles, like trapezoidal ones, defined by the user or by
a high level planner. The planning method adds a cubic polynomial function
for the last segment of the trajectory in order to reach a desired final
position of the joint. We apply this planning method to an underactuated
bipedal mechanism which gait is generated by the oscillatory movement of
its tail. Using linear frequency profiles allow us to modify the speed of
the mechanism and to study the efficiency of the system at different speed
values. |
|
Title: |
EXTENSION OF THE GENERALIZED IMAGE RECTIFICATION -
Catching the Infinity Cases |
Author(s): |
Klaus Häming and Gabriele Peters |
Abstract: |
This paper addresses the topic of image rectification,
a widely used technique in 3D-reconstruction and stereo vision. The most
popular algorithm uses a projective transformation to map the epipoles of
the images to infinity. This algorithm fails whenever an epipole lies
inside an image. To overcome this drawback, a rectification scheme known
as polar rectification can be used. This, however, fails whenever an
epipole lies at infinity. For autonomous systems exploring their
environment, it can happen that successive camera positions constitute
cases where we have an image pair with one epipole at infinity and the
other inside an image. So neither of the previous algorithms can be
applied directly. We present an extension to the polar rectification
scheme. This extension allows the rectification of image pairs whose
epipoles lie even at such difficult positions. Additionally, we discuss
the necessary computation of the orientation of the epipolar geometry in
terms of the fundamental matrix directly, avoiding the computation of a
line homography as in the original polar rectification
process. |
|
Title: |
MOTION CONTROL OF AN OMNIDIRECTIONAL MOBILE
ROBOT |
Author(s): |
Xiang Li and Andreas Zell |
Abstract: |
This paper focuses on the motion control problem of an
omnidirectional mobile robot. A new control method based on the inverse
input-output linearized kinematic model is proposed. As the actuator
saturation and actuator dynamics have important impacts on the robot
performance, this control law takes into account these two aspects and
guarantees the stability of the closed-loop control system. Real-world
experiments with an omnidirectional middle-size RoboCup robot verifies the
performance of this proposed control algorithm. |
|
Title: |
DYNAMIC REAL-TIME REDUCTION OF MAPPED FEATURES IN A 3D
POINT CLOUD |
Author(s): |
Marko Reimer and Bernardo Wagner |
Abstract: |
This paper presents a method to reduce the data
collected by a 3D laser range sensor. The complete point cloud consisting
of several thousand points is hard to process on-line and in real-time on
a robot. Similar to navigation tasks, the reduction of these points to a
meaningful set is needed for further processes of object recognition. This
method combines the data from a 3D laser sensor with an existing 2D map in
order to reduce mapped feature points from the raw data. The main problem
is the computational complexity of considering the different noise
sources. The functionality of our approach is demonstrated by experiments
for on-line reduction of the 3D data in indoor and outdoor
environments. |
|
Title: |
MAKING SENSOR NETWORKS INTELLIGENT |
Author(s): |
Peter Sapaty, Masanori Sugisaka and Joaquim
Filipe |
Abstract: |
A universal solution for management of dynamic sensor
networks will be presented, covering both networking and application
layers. A network of intelligent modules, overlaying the sensor network,
collectively interprets mission scenarios in a special high-level
language, which can start from any nodes and cover the network at runtime.
The spreading scenarios are extremely compact, which may be useful for
energy saving communications. The code will be exhibited for distributed
collection and fusion of sensor data, also for tracking mobile targets by
scattered and communicating sensors. |
|
Title: |
DATA INTEGRATION SOLUTION FOR PAPER INDUSTRY - A
Semantic Storing Browsing and Annotation Mechanism for Online Fault
Data |
Author(s): |
Sergiy Nikitin, Vagan Terziyan and Jouni
Pyötsiä |
Abstract: |
There is a lot of IT solutions exist for simplification
and time saving of industrial experts’ activities, however, due to large
diversity of tools and case-by-case software development strategy, big
industrial companies are looking for an efficient and viable information
integration solution. The companies have realized the need for an integral
environment, where information is ready for extraction and sophisticated
querying. We present here a semantic web-based solution for logging and
annotation of online fault data, which is designed, implemented and
deployed for a particular business case of a leading paper machinery
maintenance and automation company. We analyse further evolution of the
system and introduce a notion of Ubiware – a generic platform for
modelling of dynamic and changing environments consisting of autonomous
self-configurable elements. |
|
Title: |
OPTIMAL NONLINEAR IMAGE DENOISING METHODS IN
HEAVY-TAILED NOISE ENVIRONMENTS |
Author(s): |
Hee-il Hahn |
Abstract: |
The statistics for the neighbor differences between the
particular pixels and their neighbors are introduced. They are
incorporated into the filter to enhance images contaminated by additive
Gaussian and impulsive noise. The derived denoising method corresponds to
the maximum likelihood estimator for the heavy-tailed Gaussian
distribution. The error norm corresponding to our estimator from the
robust statistics is equivalent to Huber’s minimax norm. This estimator is
also optimal in the respect of maximizing the efficacy under the above
noise environment. It is mixed with the myriad filter to propose an
amplitude-limited myriad filter. In order to reduce visually grainy output
due to impulsive noise, Impulse-like signal detection is introduced so
that it can be processed in different manner from the remaining pixels.
Our approaches effectively remove both Gaussian and impulsive noise, not
blurring edges severely. |
|
Title: |
COMPARISON OF FINE NEEDLE BIOPSY CYTOLOGICAL IMAGE
SEGMENTATION METHODS |
Author(s): |
Maciej Hrebien, Piotr Stec and Józef
Korbicz |
Abstract: |
The paper describes an early stage of cytological image
recognition and presents a comparision of two hybrid segmentation methods.
The analysis includes the Hough transform with conjunction to the
watershed algorithm and with conjunction to the active contours
techniques. One can also find here a short description of image
pre-processing and an automatic nucleuses localization mechanisms used in
our approach. Preliminary experimental results collected on a
hand-prepared benchmark database are also presented with short discussion
of common errors and possible future problems. |
|
Title: |
SMARTMOBILE – AN ENVIRONMENT FOR GUARANTEED MULTIBODY
MODELING AND SIMULATION |
Author(s): |
Ekaterina Auer and Wolfram Luther |
Abstract: |
Multibody modeling and simulation is important in many
areas of our life from a computer game to space exploration. To automatize
the process for industry and research, a lot of tools were developed,
among which the program {\sc MOBILE} plays a considerable role. However,
such tools cannot guarantee the correctness of results, for example, due
to possible errors in the underlying finite precision arithmetic. To avoid
such errors and simultaneously prove the correctness of results, a number
of so called validated methods were developed, which include interval,
affine and Taylor form based arithmetics. In this paper, we present the
recently developed multibody modeling and simulation tool {\sc
SmartMOBILE} based on {\sc MOBILE}, which is able to guarantee the
correctness of results. The use of validated methods there allows us
additionally to take into account the uncertainty in measurements and
study its influence on simulation. We demonstrate the main concepts and
usage with the help of several mechanical systems, for which kinematical
or dynamic behavior is simulated in a validated way. |
|
Title: |
BLENDING TOOL PATHS FOR G1-CONTINUITY IN ROBOTIC
FRICTION STIR WELDING |
Author(s): |
Mikael Soron and Ivan Kalaykov |
Abstract: |
In certain robot applications, path planning has to be
viewed, not only from a motion perspective, but also from a process
perspective. In 3-dimensional Friction Stir Welding (FSW) a properly
planned path is essential for the outcome of the process, even though
different control loops compensate for deviations. One such example is how
sharp path intersection is handled, which is the emphasis in this paper.
We propose a strategy based on Hermite and Bezier curves, by which
G1-continuity is obtained. The blending operation includes an optimization
strategy in order to avoid high second order derivatives of the blending
polynomials, yet still to cover as mush as possible of the original path. |
|
Title: |
AUTOMATIC VISION-BASED MONITORING OF THE SPACECRAFT ATV
RENDEZVOUS / SEPARATIONS WITH THE INTERNATIONAL SPACE STATION |
Author(s): |
A. A. Boguslavsky, V. V. Sazonov, S. M. Sokolov, A. A.
Boguslavsky, V. V. Sazonov and S. M. Sokolov |
Abstract: |
The system which allows automating the visual
monitoring of the spacecraft ATV rendezvous / separations with the
international space station is being considered. The initial data for this
complex is the video signal received from the TV-camera, mounted on the
station board. The offered algorithms of this video signal processing in
real time allow restoring the basic characteristics of the spacecraft
motion with respect to the international space station. The results of the
experiments with the described software and real and virtual video data
about the docking approach of the spacecraft with the International Space
Station are being presented. The accuracy of the estimation of the motion
characteristics and perspectives of the use of the package are being
discussed. |
|
Title: |
CALIBRATION OF QUASI-ISOTROPIC PARALLEL KINEMATIC
MACHINES: ORTHOGLIDE |
Author(s): |
Anatoly Pashkevich, Roman Gomolitsky, Philippe Wenger
and Damien Chablat |
Abstract: |
The paper proposes a novel approach for the geometrical
model calibration of the quasi-isotropic parallel kinematic mechanisms of
the Orthoglide family. It is based on observations of the manipulator leg
parallelism during motions between the specific test postures and employs
a low-cost measuring system composed of standard comparator indicators
attached to the universal magnetic stands. They are sequentially used for
measuring the deviation of the relevant leg location while the manipulator
moves the TCP along the Cartesian axes. Using the measured differences,
the developed algorithm estimates the joint offsets and the leg lengths
that are treated as the most essential parameters. Validity of the
proposed calibration technique is confirmed by the experimental
results. |
|
Title: |
DIRECTIONAL MANIPULABILITY FOR MOTION COORDINATION OF
AN ASSISTIVE MOBILE ARM |
Author(s): |
K. Nait-Chabane, P. Hoppenot and E. Colle |
Abstract: |
In this paper, we address the problem of coordinated
motion control of a manipulator arm embarked on a mobile platform. The
mobile manipulator is used in providing assistance for disabled people. In
order to perform a given task by using mobile manipulator redundancy, we
propose a new manipulability measure that incorporates both arm
manipulation capacities and the end-effector imposed task. This proposed
measure is used in a numerical algorithm to solve system redundancy and
then compared with other existing measures. Simulation and real results
show the benefit and efficiency of this measure in the field of motion
coordination. |
|
Title: |
IRREVERSIBILITY MODELING APPLIED TO THE CONTROL OF
COMPLEX ROBOTIC DRIVE CHAINS |
Author(s): |
Omar Al Assad, Emmanuel Godoy and Vincent
Croulard |
Abstract: |
The phenomena of static and dry friction may lead to
difficult problems during low speed motion (e.g. stick slip phenomenon).
However, they can be used to obtain irreversible mechanical transmissions.
The latter tend to be very hard to model theoretically. In this paper, we
propose a pragmatic approach to model irreversibility in robotic drive
chains. The proposed methodology consists of using a state machine to
describe the functional state of the transmission. After that, for each
state we define the efficiency coefficient of the drive chain. This
technique gives conclusive results during experimental validation and
allows to reproduce a reliable robot simulator. This simulator is set up
for the purpose of position control of a medical positioning
robot. |
|
Title: |
A ROBOTIC PLATFORM FOR AUTONOMY STUDIES |
Author(s): |
Sergio Ribeiro Augusto and Ademar Ferreira |
Abstract: |
This paper describes a mobile robotic platform and a
software framework for applications and development of robotic experiments
integrating teleoperation and autonomy. An application using supervised
learning is developed in which the agent is trained by teleoperation. This
allows the agent to learn the perception to action mapping from the
teleoperator in real time, such that the task can be repeated in an
autonomous way, with some generalization. To make the mapping, a radial
basis function network (RBF) trained with a sequential learning algorithm
is used. Experimental results are shown. |
|
Title: |
INITIAL DEVELOPMENT OF HABLA (HARDWARE ABSTRACTION
LAYER) - A Middleware Software Tool |
Author(s): |
Andrés Faíña, Francisco Bellas and Richard J.
Duro |
Abstract: |
In this work we present the initial implementation of a
middleware software tool called the Hardware Abstraction Layer (HABLA).
This tool isolates the control architecture of an autonomous computational
system, like a robot or an “intelligent” room, from its particular
hardware implementation. It is provided with a set of general sensors and
typical sensorial processing mechanisms of this kind of autonomous systems
allowing for its application to different commercial platforms. This way,
the HABLA permits the control designer to focus its work on higher-level
tasks minimizing the time spent on the adaptation of the control
architecture to different hardware configurations. Another important
feature of the HABLA is that both hardware-HABLA and HABLA-control
communications take place through TCP sockets, permitting the distribution
of the computational cost over different computers. In addition, it has
been developed in JAVA, so it is platform independent. After presenting
the general HABLA diagram and operation structure, we consider a real
application using the same deliberative control architecture on two
different autonomous robots: an Aibo legged robot and a Pioneer 2Dx
wheeled robot. Finally, the HABLA capabilities are considered in the
framework of an “intelligent” environment control system. |
|
Title: |
MULTI-RESOLUTION BLOCK MATCHING MOTION ESTIMATION WITH
DEFORMATION HANDLING USING GENETIC ALGORITHMS FOR OBJECT TRACKING
APPLICATIONS |
Author(s): |
Harish Bhaskar and Helmut Bez |
Abstract: |
Motion Estimation is a popular technique for computing
the displacement vectors between objects or attributes between images
captured at subsequent time stamps. Block matching is a well known
technique of motion estimation that has been successfully applied to
several applications such as video coding, compression and object
tracking. One of the major limitations of the algorithm is its ability to
cope with deformation of objects or image attributes within the image. In
this paper we present a novel scheme for block matching that combines
genetic algorithms with affine transformations to accurate match blocks.
The model is adapted into a multi-resolution framework and is applied to
object tracking. A detailed analysis of the model alongside critical
results illustrating its performance on several synthetic and real-time
datasets is presented. |
|
Title: |
A NOVEL BLOCK MOTION ESTIMATION MODEL FOR VIDEO
STABILIZATION APPLICATIONS |
Author(s): |
Harish Bhaskar and Helmut Bez |
Abstract: |
With the increased use of hand-held or head-mounted
video capture devices for motion capture, the requirement for robust and
reliable video enhancement technology for stabilization has also
increased. Video stabilization algorithms primarily aim at generating
stabilized image sequences by removing unwanted shake due to small camera
movements. It is important to perform video stabilization in order to
assure more effective high level video analysis. In this paper, we propose
novel motion correction schemes based on probabilistic filters in the
context of block matching motion estimation for efficient video
stabilization. We present a detailed overview of the model and compare our
model against other block matching schemes on several real-time and
synthetic data sets. |
|
Title: |
BAYES-BASED OBJECT TRACKING BOOSTED BY PARTICLE SWARM
OPTIMIZATION |
Author(s): |
Yuhua Zheng and Yan Meng |
Abstract: |
This paper presents a novel Bayes-based object tracking
framework boosted by a particle swarm optimization (PSO) algorithm, which
is a population based searching algorithm. Basically two searching steps
are conducted in this method. First, the object model is projected into a
high-dimensional feature space, and a PSO algorithm is applied to search
over this high-dimensional space and converge to some global optima, which
are well-matched candidates in terms of object features. Second, a
Bayes-based filter is used to identify the one with the highest
possibility among these candidates under the constraint of object motion
estimation. The proposed algorithm considers not only the object features
but also the object motion estimation to speed up the searching procedure.
Experimental results demonstrate that the proposed method is efficient and
robust in object tracking. |
|
Title: |
BAYESIAN ADAPTIVE SAMPLING FOR BIOMASS ESTIMATION WITH
QUANTIFIABLE UNCERTAINTY |
Author(s): |
Pinky Thakkar, Steven M. Crunk, Marian Hofer, Gabriel
Cadden, Shikha Naik and Kim T. Ninh |
Abstract: |
Traditional methods of data collection are often
expensive and time consuming. We propose a novel data collection
technique, called Bayesian Adaptive Sampling (BAS), which enables us to
capture maximum information from minimal sample size. In this technique,
the information available at any given point is used to direct future data
collection from locations that are likely to provide the most useful
observations in terms of gaining the most accuracy in the estimation of
quantities of interest. We apply this approach to the problem of
estimating the amount of carbon sequestered by trees. Data may be
collected by an autonomous helicopter with onboard instrumentation and
computing capability, which after taking measurements, would then analyze
the currently available data and determine the next best informative
location at which a measurement should be taken. We quantify the errors in
estimation, and work towards achieving maximal information from minimal
sample sizes. We conclude by presenting experimental results that suggest
our approach towards biomass estimation is more accurate and efficient
compared to the random sampling. |
|
Title: |
COMPARISON OF FOCUS MEASURES IN FACE DETECTION
ENVIRONMENTS |
Author(s): |
J. Lorenzo, O. Déniz, M. Castrillón and C.
Guerra |
Abstract: |
This work presents a comparison among different focus
measures used in the literature for autofocusing in a non previously
explored application of face detection. This application has different
characteristics to those where traditionally autofocus methods have been
applied like microscopy or depth from focus. The aim of the work is to
find if the best focus measures in traditional applications of autofocus
have the same performance in face detection applications. To do that six
focus measures has been studied in four different settings from the oldest
to more recent ones. |
|
Title: |
REPUTATION BASED BUYER STRATEGY FOR SELLER SELECTION
FOR BOTH FREQUENT AND INFREQUENT PURCHASES |
Author(s): |
Sandhya Beldona and Costas Tsatsoulis |
Abstract: |
Previous research in the area of buyer strategies for
choosing sellers in ecommerce markets has focused on frequent purchases.
In this paper we present a reputation based buyer strategy for choosing
sellers in a decentralized, open, uncertain, dynamic, and untrusted B2C
ecommerce market for frequent and infrequent purchases. The buyer models
the reputation of the seller after having purchased goods from it. The
buyer has certain expectations of quality and the reputation of a seller
reflects the seller’s ability to provide the product at the buyer’s
expectation level, and its price compared to its competitors in the
market. The reputation of the sellers and the price quoted by the sellers
are used to choose a seller to transact with. We compare the performance
of our model with other strategies that have been proposed for this kind
of market. Our re-sults indicate that a buyer using our model experiences
a slight improvement for frequent purchases and significant improvement
for infrequent purchases. |
|
Title: |
ARTIFICIAL IMMUNE FILTER FOR VISUAL
TRACKING |
Author(s): |
Alejandro Carrasco E. and Peter Goldsmith |
Abstract: |
Visual tracking is an important part of artificial
Vision for robotics. It allows robots to move towards a desired position
using real world information. In this paper we present a novel particle
filtering method for visual tracking, based on a clonal selection and a
somatic mutation processes used by the natural immune system, which is
excellent at identifying intrusion cells; antigens. This capability is
used in this work to track motion of the object in a sequence of
images. |
|
Title: |
ON THE BALANCING CONTROL OF HUMANOID ROBOT |
Author(s): |
Youngjin Choi and Doik Kim |
Abstract: |
This paper proposes the kinematic resolution method of
CoM(center of mass) Jacobian with embedded motions, and the design method
of posture/walking controller for humanoid robots. First, the kinematic
resolution of CoM Jacobian with embedded motions makes a humanoid robot
balanced automatically during movement of all other limbs. Actually, it
offers an ability of WBC(whole body coordination) to humanoid robot.
Second, the posture/walking controller is completed by adding the CoM
controller minus the ZMP(zero moment point) controller to the suggested
kinematic resolution method. Also, we prove that the proposed
posture/walking controller brings the ISS(disturbance input-to-state
stability) for the simplified bipedal walking robot model. Finally, the
effectiveness of the suggested posture/walking control method is shown
through experiment in regard to the arm dancing of humanoid
robot. |
|
Title: |
A MODIFIED IMPULSE CONTROLLER FOR IMPROVED ACCURACY OF
ROBOTS WITH FRICTION |
Author(s): |
Stephen van Duin, Christopher D. Cook, Zheng Li and
Gursel Alici |
Abstract: |
This paper presents a modified impulse controller to
improve the steady state positioning of a SCARA robot having
characteristics of high non-linear friction. A hybrid control scheme
consisting of a conventional PID part and an impulsive part is used as a
basis to the modified controller. The impulsive part uses short width
torque pulses to provide small impacts of force to overcome static fiction
and move a robot manipulator towards its reference position. It has been
shown that this controller can greatly improve a robot’s accuracy.
However, the system in attempting to reach steady state will inevitably
enter into a small limit cycle whose amplitude of oscillation is related
to the smallest usable impulse. It is shown in this paper that by
modifying the impulse controller to adjust the width of successive pulses,
the limit cycle can be shifted up or down in position so that the final
steady state error can be even further reduced. |
|
Title: |
COMMUNICATION AT ONTOLOGICAL LEVEL IN COOPERATIVE
MOBILE ROBOTS SYSTEM |
Author(s): |
Lucia Vacariu, Mihai Chintoanu, Gheorghe Lazea and
Octavian Cret |
Abstract: |
The cooperation problems in the mobile robots systems
can be managed by using a control system based on the software paradigm of
multiagent systems. Typical tasks performed by mobile robots systems often
assume, among others, dynamic structures and various types of interactions
between agents. These are leading to large amounts of information transfer
in the communication process and the content and significance of
communication is changing continuously. Using an ontological level in the
communicating multiagents system can assure the efficiency and the
correctness of information exchange between multiagents. The quick change
of the content of communication is thus possible and this increases the
adaptability of the system. A cooperative mobile robots system for
monitoring, manipulating and cleaning in a supermarket is presented.
Simulation results with communication at ontological level validate the
system cooperation tasks. |
|
Title: |
ACTIVE 3D RECOGNITION SYSTEM BASED ON FOURIER
DESCRIPTORS |
Author(s): |
E. González, V. Feliú, A. Adán and Luis
Sánchez |
Abstract: |
This paper presents a new 3D object recognition/pose
strategy based on reduced sets of Fourier descriptors on silhouettes. The
method consists of two parts. First, an off-line process calculates and
stores a clustered Fourier descriptors database corresponding to the
silhouettes of the synthetic model of the object viewed from multiple
viewpoints. Next, an on-line process solves the recognition/pose problem
for an object that is sensed by a real camera placed at the end of a
robotic arm. The method avoids ambiguity problems (object symmetries or
similar projections belonging to different objects) and erroneous results
by taking additional views which are selected through an original next
best view (NBV) algorithm. The method provides, in very reduced
computation time, the object identification and pose of the object. A
validation test of this method has been carried out in our lab yielding
excellent results. |
|
Title: |
A STUDY OF TWO COLOR SYSTEMS USED IN CONTENT-BASED
IMAGE QUERY ON MEDICAL IMAGERY |
Author(s): |
Liana Stanescu, Dumitru Burdescu, Cosmin Stoica and
Marius Brezovan |
Abstract: |
The article presents a comparative study over two
methods used in content-based visual query. The two methods refer at two
different color systems used for representing color information from
images: HSV quantized to 166 colors and l1l2l3 quantized to 64 colors. The
originality of the study comes from the fact that it was made on a
database with medical images from digestive tract area, captured by an
endoscope. The scope was to check the quality of the content-based visual
query on images representing five different diagnoses (colitis, ulcer,
esophagitis, polyps and ulcerous tumor) and taking into consideration that
some parameters were modified during the capturing process: viewing
direction, intensity and direction of the illumination, parameters that
affect mostly the medical images captured during the diagnosis process. |
|
Title: |
INTERNET-BASED TELEOPERATION: A CASE STUDY - Toward
Delay Approximation and Speed Limit Module |
Author(s): |
Shengtong Zhong, Philippe Le Parc and Jean
Vareille |
Abstract: |
This paper presents the internet-based remote control
of mobile robot. To face unpredictable Internet delays and possible
connection rupture, a direct teleoperation architecture with “Speed Limit
Module” (SLM) and “Delay Approximator” (DA) is proposed. This direct
control architecture guarantees the path error of the robot motion is
restricted within the path error tolerance of the application. Experiment
results show the effectiveness and applicability of this direct internet
control architecture in the real internet environment. |
|
Title: |
BEHAVIOR ANALYSIS OF PASSENGER’S POSTURE AND EVALUATION
OF COMFORT CONCERNING OMNI-DIRECTIONAL DRIVING OF WHEELCHAIR |
Author(s): |
Yuta Sato, Yoshiyuki Noda, Takanori Miyoshi and
Kazuhiko Terashima |
Abstract: |
The purpose of this study is to analyze the
relationship between passenger's posture behavior and comfort while riding
omni-directional wheelchair. First, an algorithm to transform the obtained
data in the sensor coordinates using acceleration sensor into the vehicle
coordinates by means of proposed correction algorithm. Its effectiveness
is demonstrated by experiments. Second, analysis on the relationship
between acceleration of wheelchair movement, passenger's posture behavior
and comfort sensation in the riding motion to forward, backward and
lateral direction is studied. Posture behavior of passenger's head and
chest is measured by acceleration sensors, and comfort sensation of
passenger is evaluated by applying the Semantic Differential (SD) method
and a Paired Comparison Test. Finally, through a lot of experiment,
influence factors concerning comfort while riding to wheelchair are
discussed. |
|
Title: |
X3DIRECTOR - A Front-end For Modeling Web Virtual World
Navigation And Visualization Parameters |
Author(s): |
Berta Buttarazzi and Daniele Pizziconi |
Abstract: |
Currently, the last step in the evolution of digital
technologies for web interface and contents is represented by virtual
environments which, despite the appearances, are, in some cases, very
accessible and economic. In fact, more than script and vectorial graphic
languages, virtual technologies can be used by inexpert users. This paper
will provide a panorama on the functionalities of language X3D and the
identification of the cases in which is possible to use X3Director, a
Front-end For Modeling Web Virtual World Navigation And Visualization
Parameters |
|
Title: |
MODELING ON MOLTEN METAL’S PRESSURE IN AN INNOVATIVE
PRESS CASTING PROCESS USING GREENSAND MOLDING AND SWITCHING CONTROL OF
PRESS VELOCITY |
Author(s): |
Ryosuke Tasaki, Yoshiyuki Noda, Kazuhiko Terashima,
Kunihiro Hashimoto and Yuji Suzuki |
Abstract: |
This paper presents modeling and control of fluid
pressure inside a mold in a press casting process using greensand molding
as an innovative casting method. The defect-free manufactures of casting
product in the press process are very important problem. Then, it is made
clear that the press velocity control achieves to reduce the rapid
increase of fluid pressure. A mathematical model of the molten metal's
pressure in a casting mold is built by using a simplified mold and
investigated the availability by comparison with the CFD model. A pattern
of the press velocity from the high speed to the lower speed is derived by
using the mathematical model. Finally, the effectiveness of the proposed
switching velocity control has been demonstrated through CFD computer
simulations. |
|
Title: |
PREDICTIVE CONTROL BY LOCAL VISUAL DATA - Mobile Robot
Model Predictive Control Strategies Using Local Visual Information and
Odometer Data |
Author(s): |
Lluis Pacheco and Ningsu Luo |
Abstract: |
Nowadays, the local visual perception research, applied
to autonomous mobile robots, has succeeded in some important objectives,
such as feasible obstacle detection and structure knowledge. This work
relates the on-robot visual perception and sensor fusion information with
the nonlinear mobile robot control system, consisting in a differential
driven robot with a free rotating wheel. The description of the proposed
algorithms can be considered as an interesting aspect of this report. It
is developed an easily portable methodology to plan the goal achievement
by using the visual data as an available source of positions. Moreover,
the dynamic interactions of the robotic system arise from the knowledge of
a set of experimental robot models that allow the development of model
predictive control strategies based on the mobile robot platform PRIM
available in the Laboratory of Robotics and Computer Vision. The
meaningful contribution is the use of the local visual information in
order to reach a local optimal trajectory planning that approaches the
robot to the final desired configuration, while avoiding obstacle
collisions. Hence, the research is focused on the experimental aspects.
Finally, conclusions on the overall work are drawn. |
|
Title: |
NEW APPROACH TO GET AUTONOMOUS AND FAST ROBOT LEARNING
PROCESSES |
Author(s): |
R. Iglesias, M. Rodríguez, C. V. Regueiro, J. Correa,
Pablo Quintía and S. Barro |
Abstract: |
Research on robot techniques that are fast,
user-friendly, and require little application-specific knowledge by the
user, is more and more encouraged in a society where the demand of
home-care or domestic-service robots is increasing continuously. In this
context we propose a methodology which is able to achieve fast
convergences towards good robot-control policies, and reduce the random
explorations the robot needs to carry out in order to find the solutions.
The performance of our approach is due to the mutual influence that three
different elements exert on each other:reinforcement learning, genetic
algorithms, and a dynamic representation of the environment around the
robot. In fact, the influence of each element over the rest varies along
the learning process. We have applied our proposal to teach a robot how to
solve two different tasks usual in many robot applications: wall following
and door traversal. Through our proposal the robot was able to learn very
good control policies for both tasks in a short period of time even though
the representation of the environment around the robot was designed for
the wall following behaviour and not for the door traversal. |
|
Title: |
FURTHER STUDIES ON VISUAL PERCEPTION FOR PERCEPTUAL
ROBOTICS |
Author(s): |
Ozer Ciftcioglu, Michael S. Bittermann and I. Sevil
Sariyildiz |
Abstract: |
Further study on computer-based perception by vision
modelling are described. The visual perception is mathematically modelled,
where the model receives and interprets visual data from the environment.
The perception is defined in probabilistic terms so that it is in the same
way quantified. At the same time, the measurement of visual perception is
made possible in real-time. Quantifying visual perception is essential for
information gain calculation. Providing virtual environment with
appropriate perception distribution is important for enhanced distance
estimation in virtual reality. Computer experiments are carried out by
means of a virtual agent in a virtual environment demonstrating the
verification of the theoretical considerations being presented, and the
far reaching implications of the studies are pointed out. |
|
Title: |
METHODOLOGY FOR LEARNING VISUAL REACTIVE BEHAVIOURS IN
ROBOTICS THROUGH REINFORCEMENT AND IMAGE-BASED STATES |
Author(s): |
Pablo Quintía, José E. Domenech, Cristina Gamallo and
Carlos V. Regueiro |
Abstract: |
In this article the development of a methodology for
the learning of visual and reactive behaviours using reinforcement
learning is described. With the use of artificial vision the environment
is perceived in 3D, and it is possible to avoid obstacles that are
invisible to other sensors that are more common in mobile robotics.
Reinforcement learning reduces the need for intervention in behaviour
design, and simplifies its adjustment to the environment, the robot and
the task. The designed methodology aims to be general, so in order to
change the desired behaviour only the reinforcement and the filtering of
the image need to be changed. For the definition of the reinforcement a
laser sensor is used and for the definition of the states a fixed 3x3 grid
is used. The behaviours learned were wall following, object following,
corridor following and platform following. Results are presented with a
Pioneer 2 AT. Learning and testing phase has been realized on the Gazebo
3D simulator, and a test of the wall following behaviour was carried out
on a real environment. |
|
Title: |
AN IMPLEMENTATION OF HIGH AVAILABILITY IN NETWORKED
ROBOTIC SYSTEMS |
Author(s): |
Florin Daniel Anton, Theodor Borangiu and Silvia
Anton |
Abstract: |
In today’s complex enterprise environments, providing
continuous service for applications is a key component of a successful
robotized implementing of manufacturing. High availability (HA) is one of
the components contributing to continuous service provision for
applications, by masking or eliminating both planned and unplanned systems
and application downtime. This is achieved through the elimination of
hardware and software single points of failure (SPOF). A high availability
solution will ensure that the failure of any component of the solution -
either hardware, software or system management, will not cause the
application and its data to become permanently unavailable. High
availability solutions should eliminate single points of failure through
appropriate design, planning, hardware selection, software configuring,
application control, carefully environment control and change management
discipline. In short, one can define high availability as the process of
ensuring an application is available for use by duplicating and/or sharing
hardware resources managed by a specialized software component. A high
availability solution in robotized manufacturing provides automated
failure detection, diagnosis, application recovery, and node (robot
controller) re integration. The paper discusses the implementing of a high
availability solution in a robotized manufacturing line. |
|
Title: |
BELL SHAPED IMPEDANCE CONTROL TO MINIMIZE JERK WHILE
CAPTURING DELICATE MOVING OBJECTS |
Author(s): |
Arjun Nagendran, Robert C Richardson and William J.
Crowther |
Abstract: |
Catching requires the ability to predict the position
and intercept a moving object at relatively high speeds. Because catching
is a contact task, it requires an understanding of the interaction between
the forces applied and position of the object being captured. The
application of force to a mass results in a change in acceleration. The
rate of change of acceleration is called jerk. Jerk causes wear on the
manipulator over time and can also damage the object being captured. This
paper uses a curve that asymptotes to zero gradient at +/- infinity to
develop an impedance controller, to decelerate an object to a halt after
it has been coupled with the end effector. It is found that this impedance
control method minimizes the jerk that occurs during capture, and
eliminates the jerk spikes that are existent when using spring dampers,
springs or constant force to decelerate an object. |
|
Title: |
TELEOPERATION OF COLLABORATIVE MOBILE ROBOTS WITH FORCE
FEEDBACK OVER INTERNET |
Author(s): |
Ivan Petrovic, Josip Babic and Marko
Budisic |
Abstract: |
A teleoperation system has been developed that enables
two human operators to safely control two collaborative mobile robots in
unknown and dynamic environments from any two PCs connected to the
Internet by installing developed client program on them and by using
simple force feedback joysticks. On the graphical user interfaces, the
operators receive images forwarded by the cameras mounted on the robots,
and on the the joysticks they feel forces forwarded by developed obstacle
prevention algorithm based on the dynamic window approach. The amount and
direction of the forces they feel on their hands depend on the distance
and direction to the robot's closest obstacle,which can also be the
collaborating robot. To overcome the instability caused by the unknown and
varying time delay an event-based teleoperation method is employed to
synchronize actions of each robot with commands from its operator. Through
experimental investigation it is confirmed that developed teleoperation
system enables the operators to successfully accomplish collaborative
tasks in complex environments. |
|
Title: |
COORDINATED MOTION CONTROL OF MULTIPLE
ROBOTS |
Author(s): |
Wojciech Kowalczyk and Krzysztof Kozlowski |
Abstract: |
In this paper a set of robot coordination approaches is
presented. Described methods are based on formation function concept.
Accuracy of different approaches is compared using formation function time
graphs. Virtual structure method is analyzed, then virtual structure
expanded with behavioral formation feedback is presented. Finally
leader-follower scheme is described. Presented methods are illustrated by
simulation results. Differentially driven nonholonomic mobile robots were
used in simulations. |
|
Title: |
ENTANGLEMENT DETECTION OF A SWARM OF TETHERED ROBOTS IN
SEARCH AND RESCUE APPLICATIONS |
Author(s): |
T. R. Vishnu Arun Kumar and R. C.
Richardson |
Abstract: |
In urban search and rescue (USAR) applications, robots
play a pivotal role. As USAR is time sensitive, swarm of robots is
preferred over single robot for victim search. Tethered robots are widely
used in USAR applications because tether provides a means of robust data
communication and power supply. The problem with using tethers in a
collapsed, unstructured environment is tether entanglement. Entanglement
detection becomes vital in this scenario. This paper presents a novel,
low-cost approach to detect entanglement in the tether connecting two
mobile robots. The proposed approach requires neither the robots to be
localized nor an environment map. Experimental results show that the
proposed approach is effective in identifying tether
entanglement. |
|
Title: |
VISION-BASED OBSTACLE AVOIDANCE FOR A SMALL, LOW-COST
ROBOT |
Author(s): |
Chau Nguyen Viet and Ian Marshall |
Abstract: |
his paper presents a vision-based obstacle avoidance
algorithm for a small indoor mobile robot built from low-cost, and
off-the-shelf electronics. The obstacle avoidance problem in robotics has
been researched extensively and there are many well established algorithms
for this problem.However, most of these algorithms are developed for large
robots with expensive, specialised sensors, and powerful computing
platforms. We have developed an algorithm that can be implemented on very
small robots with low-cost electronics and small computing platforms. Our
vision-based obstacle detection algorithm is fast and works with very low
resolution images. The control mechanism utilises both visual information
and sonar sensor's measurement without having to fuse the data into a
model or common representation. T he robot platform was tested in an
unstructured office environment and demonstrated a reliable obstacle
avoidance behaviour. |
|
Title: |
THE PROTOTYPE OF HUMAN – ROBOT INTERACTIVE VOICE
CONTROL SYSTEM |
Author(s): |
Miroslav Holada, Igor Kopetschke, Pavel Pirkl, Martin
Pelc, Lukáš Matela, Jiří Horčička and Jakub Štilec |
Abstract: |
This contribution shows our recent activities of human
– robot control system. The keynote consists in design system that allows
easy control and programming of various robots by uniform interactive
system. Generally the robots are actuate by sets of control commands,
sometimes by hand control interface (touchpad, joystick). The operator had
to know control commands, syntax rules and other properties necessary for
successful robot control. Our system offers uniform commands like “move
left” or “elevate arm” that are translated and sent into corresponding
device (robot). Speech recognition is based on isolated-word HMM engine
with distributed recognition system (DSR). The vocabulary can contain
thousands word and short phrases. It allows us design easy dialogue
scenario for robot control system. The system allows direct robot control
like moving or programming short sequences. The video camera is included
for displaying working place. The algorithms of image processing allow to
detect the position of objects in working area and facilitate robot
navigation. |
|
Title: |
ROBOT TCP POSITIONING WITH VISION - Accuracy Estimation
of a Robot Visual Control System |
Author(s): |
Drago Torkar and Gregor Papa |
Abstract: |
A calibrated 3D visual servoing has not fully matured
as a technology yet. In order to widen its use in industrial applications
its technological capability must be precisely known. The accuracy and
repeatability are two of the crucial parameters in planning of any robotic
task. In this paper we describe a procedure to evaluate the 2D the 3D
accuracy of a robot stereo vision system consisted of two identical 1
Megapixel cameras, and present the results of the evaluation. |
|
Title: |
HYBRID MOTION CUEING ALGORITHMS FOR REDUNDANT ADVANCED
DRIVING SIMULATORS |
Author(s): |
Hatem Elloumi, Nadia Maïzi and Marc Bordier |
Abstract: |
Redundant Advanced Driving Simulators (hexapods mounted
on rails) present an extra capability to reproduce motion sensations. The
exploitation of this capability is currently done by frequency separation
methods without taking into account the frequency overlapping between the
hexapod and the rails. Within this bandwidth, these two degrees of freedom
could be considered as equivalent. Our aim is to use this equivalence to
improve the motion restitution. We offer two algorithms based on the
hybrid systems framework which deal with the longitudinal mode. Their goal
is to improve the restitution of motion sensations by reducing false cues
(generated by actuators braking) and decreasing null cues (due to
actuators blocking). Our algorithms include and treat all steps of motion
cueing: motion tracking (restitution), braking before reaching the
displacement limits, washout motion, and switching rules. |
|
Title: |
ESCAPE LANES NAVIGATOR - To Control “RAOUL” Autonomous
Mobile Robot |
Author(s): |
Nicolas Morette, Cyril Novales and Laurence Josserand |
Abstract: |
This paper presents a navigation method to control
autonomous mobile robots : the escapes lanes, applied to RAOUL mobile
system. First, the formalism is introduced to model an automated system,
and then is applied to a mobile robot. Then, this formalism is used to
describe the escape lanes navigation method, and is applied to our RAOUL
mobile robot. Finally, implementation results simulations validate the
concept. |
|
Title: |
HUMAN-SCALE VIRTUAL REALITY CATCHING ROBOT SIMULATION |
Author(s): |
Ludovic Hamon, François-Xavier Inglese and Paul
Richard |
Abstract: |
This paper presents a human-scale virtual reality
catching robot simulation. The virtual robot catches a ball that users
throw in its workspace. User interacts with the virtual robot using a
large-scale bimanual haptic interface. This interface is used to track
user’s hands movements and to display weight and inertia of the virtual
balls. Stereoscopic viewing, haptic and auditory feedbacks are provided to
improve user’s immersion and simulation realisms. |
|
Title: |
REAL-TIME INTER- AND INTRA- CAMERA COLOR MODELING AND
CALIBRATION FOR RESOURCE CONSTRAINED ROBOTIC PLATFORMS |
Author(s): |
Walter Nisticò and Matthias Hebbel |
Abstract: |
This paper presents an approach to correct chromatic
distortion within an image (vignetting) and to compensate for color
response differences among similar cameras which equip a team of robots,
based on Evolutionary Algorithms. Our black-box approach does not make
assumptions concerning the physical/geometrical roots of the distortion,
and the efficient implementation is suitable for real time applications on
resource constrained platforms. |
|
Title: |
SCADA WEB - Remote Supervision and Maintenance of
Industrial Processes |
Author(s): |
José Ramón Janeiro, Eduardo J. Moya, David García,
Oscar Calvo and Clemente Cárdenas |
Abstract: |
This article explains a SCADA System called SCADA Web
developed by CARTIF Foundation. This SCADA System makes possible remote
monitoring and control from the process controlled by PLC using Web
Technology. SCADA Web has been developed on platform Java EE and provides
visualization and control signals, trend charts, alarms, historical data
and alarm reports. |
|
Title: |
A NOVEL STRATEGY FOR EXPLORATION WITH MULTIPLE
ROBOTS |
Author(s): |
Jonathan Rogge and Dirk Aeyels |
Abstract: |
The present paper develops a novel strategy for the
exploration of an unknown environment with a multi-robot system. Contrary
to most exploration problems, the topographical properties of the space
need not be mapped. The algorithm we propose is inspired by methods used
for complete coverage of an area, where all free space has to be
physically covered by all robots. In the present paper it is required that
the entire free space is covered by the {\it sensors} of the robots, with
a certainty of $100\%$. This weaker requirement enables us to scan more
space in less time, compared to complete coverage algorithms. Moreover the
shape of the robot formation adjusts itself to situations where obstacles,
narrow spaces, etc. have to be passed. Communication between the robots is
restricted to line-of-sight and to a maximum interdistance between robots.
A direct application of the algorithm is mine field clearance. |
|
Title: |
IMPROVED OCCUPANCY GRID LEARNING - The ConForM Approach
to Occupancy Grid Mapping |
Author(s): |
Thomas Collins, J. J. Collins and Conor
Ryan |
Abstract: |
A central requirement for the development of robotic
systems, that are capable of autonomous operation in non-specific
environments, is the ability to create maps of their operating locale.
These maps can subsequently serve as the basis for planning and problem
solving activities. The creation of these maps is a non trivial process as
the robot has to interpret the findings of its sensors so as to make
deductions regarding the state of its environment. Current approaches to
the robotic mapping problem fall into two broad categories: on-line and
offline. An on-line approach is characterised by its ability to construct
a map as the robot traverses its operating environment, however this comes
at the cost of representational clarity. An offline approach on the other
hand requires that all sensory data be gathered before processing begins
but is capable of creating more accurate maps. In this paper we present a
new means of constructing occupancy grid maps which addresses this
problem. |
|
Title: |
THE TELE-ECHOGRAPHY MEDICAL ROBOT OTELO2 - Teleoperated
with a Multi Level Architecture using Trinomial Protocol |
Author(s): |
Gwenaël Charron, Aïcha Fonte, Pierre Vieyres Philippe
Fraisse, Lama Al Bassit and Cyril Novales |
Abstract: |
This paper presents a novel architecture applied to a
mobile teleoperated medical robotic system: OTELO2 (MObile Tele-Echography
using an Ultra-Light RObot); OTELO2 performs a tele-echography at a
distance for the benefit of medically isolated sites. First, this paper
presents an overview of the OTELO2 teleoperated system. Then, it describes
the modular control architecture used and the integration of the
teleoperated layer on this multi level architecture. Finally, it presents
the communication links used to control this system, as well as some
experimental results. |
|
Title: |
MATHEMATICAL MODEL FOR WALKING ROBOT WITH SHAPE MEMORY
ALLOY ANKLE |
Author(s): |
Anca Petrişor, Nicu George Bîzdoacă, Daniela Roşca,
Sonia Degeratu, Adrian Roşca and Raducu Petrisor |
Abstract: |
The paper present a simultaneous force and length
variation mode shape memory alloy (SMA) robotic application. The robotic
ankle contains four SMA actuators and a spherical articulation. In order
to assure a high efficient robotic architecture, the mechanical and the
control structure have to assure a real-time response to the work
environment changes. The load variations or the difference between the
moment of full contact step and the non contact moment for a waking robot
are the standard situations for a SMA robotic ankle. The paper is divided
in five sections. First section makes a short introduction in the physical
description and conventional applications of shape memory alloy materials.
Then are presented the mathematical model for robotic ankle, the walking
robot geometrical structure and the causality ordering of the active pair
of legs, in this case with one free joint. In the last section are
presented some experimental results obtained by using a platform,
conceived by authors in MATLAB environment, for design and simulation of
walking robots control algorithms. |
|
Title: |
KAMANBARÉ - A Tree-climbing Biomimetic Robotic Platform
for Environmental Research |
Author(s): |
Reinaldo de Bernardi and José Jaime da Cruz |
Abstract: |
Environmental research is an area where robotics
platforms can be applied as solutions for different problems to help or
automate certain tasks, with the purpose of being more efficient or also
safer for the researchers involved. This paper presents the Kamanbaré
platform. Kamanbaré is a bioinspired robotic platform, whose main goal is
to climb trees for environmental research applications, applied in tasks
such as gathering botanical specimen, insects, climatic and arboreal fauna
studies, among others. Kamanbaré is a platform that provides flexibility
both in hardware and software, so that new applications may be developed
and integrated without the need of extensive knowledge in
robotics. |
|
Title: |
A MULTIROBOT SYSTEM FOR DISTRIBUTED SENSING |
Author(s): |
Janne Haverinen, Anssi Kemppainen, Janne Kivijakola and
Juha Röning |
Abstract: |
This paper presents a modular multirobot system
developed for distributed sensing experiments. The multirobot system is
composed of modular small size robots, which have various sensor
capabilities including a color stereo camera system and an infrared based
sensor for the relative pose estimation. The paper describes the current
state of the multirobot system introducing the robots, their sensor
capabilites, and some initial experiments conducted with the system. The
experiments include a distributed laser based 3-D scanning experiment
involving two robots, and an experiment where a group of robots arrange
into a spatial formation and measures the distributions of light and
magnetic field of the environment. The experiments demonstrate how a
multirobot system can be used in a meaningful way to extract information
from the environment, and how they can cooperatively perform tasks, like
3-D scanning, which is a difficult task for a single small size robot due
to limitations of current sensing technologies. The 3-D scanning
experiment also demonstrates how the multirobot system's inherent
properties, i.e. spatial distribution and mobility, can be utilized in a
novel way to create distributed measurement devices in which each robot
has an role as a part of the device, and in which the mobility of the
robots provides flexibility to the structure of the measurement system. |
|
Title: |
USING SIMPLE NUMERICAL SCHEMES TO COMPUTE VISUAL
FEATURES WHENEVER UNAVAILABLE - Application to a Vision-Based Task in a
Cluttered Environment |
Author(s): |
FOLIO David and CADENAT Viviane |
Abstract: |
In this paper, we propose to apply classical numerical
integration algorithms to determine the visual features when they are lost
or unavailable during a vision-based navigation task. The developed
methods have been tested both in simulation and experimentation, with
interesting results. A comparative analysis is also provided to select the
most interesting techniques depending on the context of use. |
|
Title: |
MINIMUM COST PATH SEARCH IN AN UNCERTAIN-CONFIGURATION
SPACE |
Author(s): |
Eric Pierre and Romain Pepy |
Abstract: |
The object of this paper is to propose a minimum cost
path search algorithm in an uncertain-configuration space and to give its
proofs of optimality and completeness. In order to achieve this goal, we
focus on one of the simpler and efficient path search algorithm in the
configuration space : the A* algorithm. We then add uncertainties and deal
with them as if they were simple dof (degree of freedom). Next, we
introduce towers of uncertainties in order to improve the efficiency of the
search. Finally we prove the optimality and completeness of the resulting
algorithm. |
|
Title: |
INCLUSION OF ELLIPSOIDS |
Author(s): |
Romain Pepy and Eric Pierre |
Abstract: |
We present, in this paper, a ready-to-use inclusion
detection for ellipsoids. Ellipsoids are used to represent configuration
uncertainty of a mobile robile. This kind of test is used in path planning
to find the optimal path according to a safety criteria. |
|
Title: |
INTROSPECTION ON CONTROL-GROUNDED CAPABILITIES - A Task
Allocation Study Case in Robot Soccer |
Author(s): |
Christian G. Quintero M., Salvador Ibarra M., Josep Ll.
De la Rosa and Josep Vehí |
Abstract: |
Our proposal is aimed at achieving reliable task
allocation in cooperative agent-controlled systems by means of
introspection on control-oriented features. This new approach is
beneficial as it improves the way agents can coordinate with each other to
perform the proposed tasks in a real cooperative environment.
Introspection aims at including reliable control-oriented knowledge of the
controlled systems in the agents’ decision-making. To that end,
control-grounded capabilities, inspired by the agent metaphor, are used in
the task utility/cost functions. Such control-grounded capabilities
guarantee an appropriate agent-oriented representation of the
specifications and other relevant details encapsulated in every automatic
controller of the controlled systems. In particular, this proposal is
demonstrated in the successful performing of rescue operations by
cooperative mobile robots in a simulated environment. Experimental results
and conclusions are shown, stressing the relevance of this new approach in
the sure and trustworthy attainment of allocated tasks for improving
multi-agent performance. |
|
Title: |
THEORY OF STRUCTURED INTELLIGENCE - Results on
Innovation-based and Experience-based Behaviour |
Author(s): |
Meike Jipp and Essameddin Badreddin |
Abstract: |
An agreed-upon general theory of intelligence would
enable significant scientific progress in all disciplines doing research
on intelligence. Such a theory, namely the theory of structured
intelligence is tested by relating it to other theories in the field and
by empirically testing it. The results demonstrate (1) that the theory of
structured intelligence, uses a similar concept of intelligence as do
other theories and (2) that its distinction between innovation- and
experience-based solutions can be found in the behaviour of the study’s
participants. This yields the opportunity to (1) allow technically testing
intelligence in an easier and less time-consuming ways as do traditional
intelligence tests, and (2) allow technology classifying the intelligence
of its user and using adaptive interfaces reducing the possibility of
serious handling errors. |
|
Title: |
A DISTRIBUTED MULTI-ROBOT SENSING SYSTEM USING AN
INFRARED LOCATION SYSTEM |
Author(s): |
Anssi Kemppainen, Janne Haverinen and Juha
Röning |
Abstract: |
Distributed sensing refers to measuring systems where
instead of one sensor multiple sensors are spatially distributed improving
robustness of the system, increasing relevancy of the measurements and
cutting costs since requiring smaller and less precise sensors. Spatially
distributed sensors fuse their measurements into the same coordinates
requiring relative positions of the sensors. In this paper, we present a
distributed multi-robot sensing system in which relative poses (positions
and orientations) among robots are estimated using an infrared location
system. The relative positions are estimated using intensity and bearing
measurements of the received infrared signals. The relative orientations
are obtained by fusing position estimates among robots. The location
system enables a group of robots to perform distributed and cooperative
environment sensing by maintaining a given formation while the group
measures distributions of light and magnetic field, for example. In the
experiments, a group of three robots moves and collects spatial
information (i.e. illuminance and compass heading) from the given
environment. The information is stored into grid maps and illustrated in
the figures presenting illuminance and compass heading. The experiments
proved the feasibility of the distributed multi-robot sensing system for
sensing applications where the environment requires moving
platforms. |
|
Title: |
DISTURBANCE FEED FORWARD CONTROL OF A HANDHELD PARALLEL
ROBOT |
Author(s): |
Achim Wagner, Matthias Nübel, Essam Badreddin, Peter P.
Pott and Markus L. Schwarz |
Abstract: |
A model-based control approach for a surgical parallel
robot is presented, which combines a local tool stabilization with a
global disturbance feed forward control. The robot is held in the
operator's hand during the manipulation of bones. For a precise processing
the tool has to be decoupled from disturbances due to unintentional hand
movements of the surgeon at the robot base. The base disturbances are
transformed for a feed forward control using the inverse dynamics of the
robot. Simulations show that disturbances can be reduced by many orders
depending on sensor errors and delay. |
|
Title: |
BEHAVIOR BASED DESCRIPTION OF DEPENDABILITY - Defining
a Minium Set of Attributes for a Behavioral Description of
Dependability |
Author(s): |
Jan Rüdiger, Achim Wagner and Essam
Badreddin |
Abstract: |
Dependability is widely understood as an integrated
concept that consists of different attributes. The set of attributes and
requirements of each attribute varies from application to application thus
making it very challenging to define dependability for a broad amount of
application. The dependability, however, is of great importance when
dealing with autonomous or semi-autonomous systems, thus defining
dependability for those kind of system is vital. Such autonomous mobile
system are usually described by their behavior. In this paper a minimum
set of attributes for the dependability of autonomous mobile systems is
proposed based on a behavioral definition of dependability. |
|
Title: |
KINEMATICS AND DYNAMICS ANALYSIS FOR A HOLONOMIC
WHEELED MOBILE ROBOT |
Author(s): |
Ahmed El-Shenawy, Achim Wagner and Essam
Badreddin |
Abstract: |
This paper presents the kinematics and the dynamics
analysis of the holonomic mobile robot C3P. The robot has three caster
wheels with modular wheel angular velocities actuation. The forward
dynamics model which is used during the simulation process is discussed
along with the robot inverse dynamics solution. The inverse dynamics
solution is used to overcome the singularity problem, which is observed
from the kinematic modeling. Since both models are different in principle
they are analyzed using simulation examples to show the effect of the
actuated and non actuated wheel velocities on the robot response. An
experiment is used to illustrate the performance of the inverse dynamic
solution practically. |
|
Title: |
LOW COST SENSING FOR AUTONOMOUS CAR DRIVING IN
HIGHWAYS |
Author(s): |
André Gonçalves, André Godinho and João
Sequeira |
Abstract: |
This paper presents a viability study on autonomous car
driving in highways using low cost sensors for environment perception. The
solution is based on a simple behaviour-based architecture implementing
the standard perception-to-action scheme. The perception of the
surrounding environment is obtained through the construction of an
occupancy grid based on the processing of data from a single video camera
and a small number of ultrasound sensors. A finite automaton integrates a
set of primitive behaviours defined after the typical human highway
driving behaviors. The system was successfully tested in both simulations
and in a laboratory environment using a mobile robot to emulate the
car-like vehicle. The robot was able to navigate in an autonomous and safe
manner, performing trajectories similar to the ones carried out by human
drivers. The paper includes results on the perception obtained in a real
highway that support the claim that low cost sensing can be effective in
this problem. |
|
Title: |
COLLABORATIVE CONTROL IN A HUMANOID DYNAMIC
TASK |
Author(s): |
Diego Pardo and Cecilio Angulo |
Abstract: |
This paper describes a control scheme that allows to
govern the dynamic behavior of an articulated mobile robot with several
degrees of freedom (DOF) and redundancies. These types of robots need a
high level of coordination between the motors performance to complete
their motions. A collaborative scheme is employed, where the actuators
involved in a specific task share information, computing integrated
control actions. The control functions are found using a stochastic
reinforcement learning technique allowing the robot to automatically
generate them based on experiences. This type of control is based on a
modularization principle: complex overall behavior is the result of the
interaction of individual simple components.\\ Unlike the standard
procedures, the control approach is not meant to follow a trajectory
generated by a planner, instead, it emerges as a consequence of the
collaboration between joints movements that seek to achieve a goal. The
learning of the sensorimotor coordination in a simulated humanoid is
presented as a demonstration. |
|
Title: |
GRASP CONFIGURATION MATCHING - Using Visual and Tactile
Sensor Information |
Author(s): |
Madjid Boudaba and Alicia Casals |
Abstract: |
Finding the global shape of a grasped object directly
from touch is time consuming and not highly reliable. This paper describes
the relationship between visual features and grasp planning, and
correlates visual and tactile information for a better description of the
object's shape and grasping points determination. The grasping process
proposed is experimented with a three fingered robotic hand. |
|
Title: |
A HUMAN AIDED LEARNING PROCESS FOR AN ARTIFICIAL IMMUNE
SYSTEM BASED ROBOT CONTROL - An Implementation on an Autonomous Mobile
Robot |
Author(s): |
Jan Illerhues and Nils Goerke |
Abstract: |
In this paper we introduce a pre-structured learning
process that enables a teacher to build a robot control. This controller
maps sensor data of a real, autonomous robot to its motor values. The kind
of mapping is defined by a teacher. The learning process is divided into
four phases and leads the agent from a supervised learning system to a
reinforcement learning, and finally to an autonomous learning system. At
the beginning the controller starts completely without knowledge, and
learns some new behaviours in the first two phases by interacting with its
teacher. In the third phase of the learning process the teacher evaluates
the states which the robot achieves by performing the behaviours taught in
phase 1 and 2. In the fourth phase the robot gains experience by
evaluating the transitions of the different behavioral states. The result
of each process phase is stored in a rule-like association system (RLA),
which is derived from the artificial immune system. The experience gained
throughout the whole learning process serves as a knowledge base for
planning actions to complete a task given by the teacher. This paper
presents the learning process, its implementation, and its
results. |
|
Title: |
AN INCREMENTAL MAPPING METHOD BASED ON A
DEMPSTER-SHAFER FUSION ARCHITECTURE |
Author(s): |
Melanie Delafosse, Laurent Delahoche, Arnaud Clerentin
and Anne-Marie Jolly-Desodt |
Abstract: |
Firstly this article presents a multi-level
architecture permitting the localization of a mobile platform and secondly
an incremental construction of the environment’s map. The environment will
be modeled by an occupancy grid built with information provided by the
stereovision system situated on the platform. The reliability of these
data is introduced to the grid by the propagation of uncertainties managed
thanks to the theory of the Transferable Belief Model. |
|
Title: |
OPTICAL NAVIGATION SENSOR - Incorporating Vehicle
Dynamics Information in Mapmaking |
Author(s): |
Tibor Takács and Viktor Kálmán |
Abstract: |
Accurate odometry and navigation may well be the most
important tasks of a mobile robot’s control system. To solve this task it
is necessary to utilize proper sensors which provide reliable information
about the motion. This paper presents the prototype of an optical
correlation sensor which can be an alternative choice for the dead
reckoning navigation system of a vehicle or mobile robot. The last part of
the paper presents an other application in an inertial navigation system
that enables a new approach to map making which incorporates vehicle
dynamics into the world map. |
|
Title: |
FORMAL VERIFICATION OF SAFETY BEHAVIOURS OF THE OUTDOOR
ROBOT RAVON |
Author(s): |
Martin Proetzsch, Karsten Berns, T. Schuele and K.
Schneider |
Abstract: |
This paper presents an approach to the formal
verification of safety properties of the behaviour-based control network
of the mobile outdoor robot RAVON. In particular, we consider behaviours
that are used for the computation of the projected vehicle's velocity from
obstacle proximity sensor data and inclination information. We describe
how this group of behaviours is implemented in the synchronous language
Quartz in order to be formally verified using model checking techniques of
the Averest verification framework. Moreover, by integrating the
automatically generated and verified code into the behaviour network, it
can be guaranteed that the robot slows down and stops as required by the
given safety specifications. |
|
Title: |
OBSTACLE DETECTION IN MOBILE OUTDOOR ROBOTS - A
Short-term Memory for the Mobile Outdoor Platform RAVON |
Author(s): |
H. Schäfer, M. Proetzsch and K. Berns |
Abstract: |
In this paper a biologically inspired approach for
compensating the limited angle of vision in obstacle detection systems of
mobile robots is presented. Most of the time it is not feasible to
exhaustively monitor the environment of a mobile robot. In order to
nonetheless achieve safe navigation obstacle detection mechanisms need to
keep in mind certain aspects of the environment. In mammals this task is
carried out by the creature's short-term memory. Inspired by this concept
an absolute local map storing obstacles in terms of representatives has
been introduced in the obstacle detection and avoidance system of the
outdoor robot RAVON. That way the gap between the fields of vision of two
laser range finders can be monitored which prevents the vehicle from
colliding with obstacles seen some time ago. |
|
Title: |
A COMPUTATIONALLY EFFICIENT GUIDANCE SYSTEM FOR A SMALL
UAV |
Author(s): |
Guillaume Ducard and Hans P. Geering |
Abstract: |
In this paper, a computationally efficient guidance
algorithm has been designed for a small aerial vehicle. It is capable of
avoiding known no-fly zones (NFZ) or obstacles detected during the flight
and also capable of taking into account reduction in the aircraft
performance. Preflight path planning only consists in storing a few way
points guiding the aircraft to its target. The paper presents an efficient
way to model no-fly zones and to generate a path in real-time to avoid the
obstacle, even in the event of reduced aircraft performance. |
|
Title: |
DESIGN OF LOW INTERACTION DISTRIBUTED DIAGNOSERS FOR
DISCRETE EVENT SYSTEMS |
Author(s): |
J. Arámburo-Lizárraga, E. López-Mellado and A.
Ramírez-Treviño |
Abstract: |
This paper deals with distributed fault diagnosis of
discrete event systems (DES). The approach held is model based: an
interpreted Petri net (IPN) describes both the normal and faulty behaviour
of DES in which both places and transitions may be non measurable. The
diagnoser monitors the evolution of the DES outputs according to a model
that describes the normal behaviour of the DES. A method for designing a
set of distributed diagnosers is proposed; it is based on the
decomposition of the DES model into reduced sub-models which require
minimal interaction among them; the diagnosability property is studied for
the set of resulting sub-models. |
|
Title: |
GEOMETRIC CONTROL OF A BINOCULAR HEAD |
Author(s): |
Eduardo Bayro-Corrochano and Julio
Zamora-Esquivel |
Abstract: |
In this paper the authors use geometric algebra to
formulate the differential kinematics of a binocular robotic head and
reformulate the interaction matrix in terms of the lines that represent
the principal axes of the camera. This matrix relates the velocities of 3D
objects and the velocities of their images in the stereo images. Our main
objective is the formulation of a kinematic control law in order to close
the loop between perception and action, which allows to perform a smooth
visual tracking. |
|
Title: |
GEOMETRIC ADVANCED TECHNIQUES FOR ROBOT GRASPING USING
STEREOSCOPIC VISION |
Author(s): |
Julio Zamora-Esquivel and Eduardo
Bayro-Corrochano |
Abstract: |
In this paper the authors propose geometric techniques
to deal with the problem of grasping of the objects relaying on their
mathematical models. For that we use the geometric algebra framework to
formulate the kinematics of a three finger robotic hand. Our main
objective is by formulating a kinematic control law to close the loop
between perception and actions. This allows us to perform a smooth
visually guided object grasping. |
|
Title: |
DYNAMIC SENSOR NETWORKS: AN APPROACH TO OPTIMAL DYNAMIC
FIELD COVERAGE |
Author(s): |
Simone Gabriele and Paolo Di Giamberardino |
Abstract: |
In the paper a solution to the sensor network coverage
problem is proposed, based on the usage of moving sensors that allow a
larger fiels coverage using a smaller number of devices. The problem than
moves from the optimal allocation of fixed or almost fixed sensors to the
determination of optimal trajectories for moving sensors. In the paper a
suboptimal solution obtained from the sampled optimal problem is given.
First, in order to put in evidence the formulation and the solution
approach to the optimization problem, a single moving sensor has been
addresed. Then, the results for multisensor systems are shown. Some
simulation results are also reported to show the behaviour of the sensors
network. |
|
Title: |
HOMOGRAPHY-BASED MOBILE ROBOT MODELING FOR DIGITAL
CONTROL IMPLEMENTATION |
Author(s): |
Andrea Usai and Paolo Di Giamberardino |
Abstract: |
The paper addresses the development of a kinematic
model for a system composed by a nonholonomic mobile robot and a camera
used as feedback sensor to close the control loop. It is shown that the
proposed homography-based model takes a particular form that brings to a
finite sampled equivalent model. The design of a multirate digital
controlis then descibed and discussed, showing that exact solutions are
obtained. Simulation results are also reported toput in evidence the
effectiveness of the solution proposed. |
|
Title: |
FEATURE DETECTION ALGORITHM FOR AUTONOMOUS CAMERA
CALIBRATION |
Author(s): |
Kyung min Han and Guilherme N. DeSouza |
Abstract: |
This paper presents an adaptive and robust algorithm
for automatic corner detection. Ordinary camera calibration methods
require that a set of feature points – usually, corner points of a
chessboard type of pattern – be presented to the camera in a controlled
manner. On the other hand, the proposed approach automatically locates the
feature points even in the presence of cluttered background, change in
illumination, arbitrary poses of the pattern, etc. As the results
demonstrate, the proposed technique is much more appropriate to automatic
camera calibration than other existing methods. |
|
Title: |
A DUAL MODE ADAPTIVE ROBUST CONTROLLER FOR DIFFERENTIAL
DRIVE TWO ACTUATED WHEELED MOBILE ROBOT |
Author(s): |
Samaherni M. Dias, Aldayr D. Araujo and Pablo J.
Alsina |
Abstract: |
This paper is addressed to dynamic control problem of
nonholonomic differential wheeled mobile robot. It presents a dynamic
controller to mobile robot, which requires only information of the robot
configuration, that are collected by an absolute positioning system. The
control strategy developed uses a linear representation of mobile robot
dynamic model. This linear model is decoupled into two single-input
single-output systems, one to linear displacement and one to angle of
robot. For each resulting system is designed a dual-mode adaptive robust
controller, which uses as inputs the reference signals calculated by a
kinematic controller. Finally, simulation results are included to
illustrate the performance of the closed loop system. |
|
Title: |
ON GENERATING GROUND-TRUTH TIME-LAPSE IMAGE SEQUENCES
AND FLOW FIELDS |
Author(s): |
Vladimír Ulman and Jan Hubený |
Abstract: |
The availability of time-lapse image sequencies
accompanied with appropriate ground-truth flow fields is crucial for
quantitative evaluation of any optical flow computation method. Moreover,
since these methods are often part of automatic object-tracking or
motion-detection solutions used mainly in robotics and computer vision, an
artificially generated high-fidelity test data is obviously needed. In
this paper, we present a framework that allows for automatic generation of
such image sequences based on real-world model image together with an
artificial flow field. The framework benefits of a two-layered approach in
which user-selected foreground is locally moved and inserted into an
artificially generated background. The background is visually similar to
the input real image while the foreground is extracted from it and so its
fidelity is guaranteed. The framework is capable of generating 2D and 3D
image sequences of arbitrary length. A brief discussion as well as an
example of application in optical microscopy imaging is
presented. |
|
Title: |
ON THE FORCE/POSTURE CONTROL OF A CONSTRAINED SUBMARINE
ROBOT |
Author(s): |
Ernesto Olguín-Díaz and Vicente Parra-Vega |
Abstract: |
An advanced, yet simple, controller for submarine
robots is proposed to achieve simultaneously tracking of time-varying
contact force and posture, without any knowledge of its dynamic
parameters. Structural properties of the submarine robot dynamic are used
to design passivity-based controllers. A representative simulation study
provides additional insight into the closed-loop dynamic properties for
regulation and tracking cases. A succinct discussion about inherent
properties of the open-loop and closed-loop systems finishes this
work. |
|
Title: |
DEVELOPMENT OF AN AUTOMATED DEVICE FOR SORTING SEEDS -
Application on Sunflower Seeds |
Author(s): |
Vincent Muracciole, Patrick Plainchault, Dominique
Bertrand and Maria Rosaria Mannino |
Abstract: |
Purity analysis and determination of other seeds by
number are still made manually. It is a repetitive task based upon visual
analysis. Our work objective is to create and use a simple and quick
automated system to do this task. A first step of this machine has been
reached by validating the image acquisition and feeding process. The
principle of this machine is based on a seeds fall with stroboscopic
effect image acquisition. This article presents the first step of creating
a dedicated and autonomous machine which combines embedded constraints and
real time processes. |
|
Title: |
A NEW PROBABILISTIC PATH PLANNER - For Mobile Robots
Comparison with the Basic RRT Planner |
Author(s): |
Sofiane Ahmed Ali, Eric Vasselin and Alain
Faure |
Abstract: |
The rapidly exploring random trees (RRTs) have
generated a highly successful single query planner which solved difficult
problems in many applications of motion planning in recent years. Even
though RRT works well on many problems, they have weaknesses in
environments that handle complicated geometries. Sampling narrow passages
in a robot’s free configuration space remains a challenge for RRT planners
indeed; the geometry of a narrow passage affects significantly the
exploration property of the RRT when the sampling domain is not well
adapted for the problem. In this paper we characterize the weaknesses of
the RRT planners and propose a general framework to improve their
behaviours in difficult environments. We simulate and test our new planner
on mobile robots in many difficult static environments which are
completely known, simulations show significant improvements over existing
RRT based planner to reliably capture the narrow passages areas in the
configuration space |
|
Title: |
AN AUGMENTED STATE VECTOR APPROACH TO GPS-BASED
LOCALIZATION |
Author(s): |
Francesco Capezio, Antonio Sgorbissa and Renato
Zaccaria |
Abstract: |
The ANSER project (Airport Night Surveillance Expert
Robot) is described, exploiting a mobile robot for autonomous surveillance
in civilian airports and similar wide outdoor areas. The paper focuses on
the localization subsystem of the patrolling robot, composed of a
non-differential GPS unit and a laser rangefinder for map-based
localization (inertial sensors are absent). Moreover, it shows that an
augmented state vector approach and an Extended Kalman filter can be
successfully employed to estimate the colored components in GPS noise,
thus getting closer to the conditions for the EKF to be
applicable |
|
Title: |
FORWARD KINEMATICS AND GEOMETRIC CONTROL OF A MEDICAL
ROBOT - Application to Dental Implantation |
Author(s): |
Richard Chaumont, Eric Vasselin and Dimitri
Lefebvre |
Abstract: |
Recently, robotics has found a new field of research in
surgery in which it is used as an assistant of the surgeon in order to
promote less traumatic surgery and minimal incision of soft tissue. In
accordance with the requirements of dental surgeons, we offer a robotic
system dedicated to dental implants. A dental implant is a mechanical
device fixed into the patient’s jaw. It is used to replace a single tooth
or a set of missing teeth. Fitting the implant is a difficult operation
that requires great accuracy. This work concerns the prototype of a
medical robot. Forward and inverse kinematics as dynamics are considered
in order to drive a control algorithm which is as accurate and safe as
possible. |
|
Title: |
HIGHER ORDER SLIDING MODE STABILIZATION OF A CAR-LIKE
MOBILE ROBOT |
Author(s): |
F. Hamerlain, K. Achour, T. Floquet and W.
Perruquetti |
Abstract: |
In this paper, we are concerned with the robust
stabilization of a car-like mobile robot given in a perturbed chained
form. A higher order sliding mode control strategy is elaborated. This
control strategy switches between two different sliding mode controls: a
second order one (super-twisting algorithm) and a new third order sliding
mode control that performs a finite time stabilization. The proposed third
sliding mode controller is based on geometric homogeneity property with a
discontinuous term. Simulation results show the control
performance. |
|
Title: |
FUZZY LOGIC ALGORITHM FOR MOBILE ROBOT
CONTROL |
Author(s): |
Viorel Stoian and Cristina Pana |
Abstract: |
This paper presents a fuzzy control algorithm for the
mobile robots that are moving next to the obstacle boundaries avoiding the
collisions with these. Four motion cycles (programs) which depend of the
proximity levels and which are followed by the mobile robot on the
trajectory (P1, P2, P3, and P4) are shown. The directions of the movements
inside every cycle for every proximity level that is reached are
presented. The sequence of the programs that depend of the proximity
levels that are reached is indicated. The motion control algorithm is
presented by a logical diagram of the evolution of the functional cycles
(programs). The fuzzy rules for evolution (transition) of the programs and
for the motion on X-axis and Y-axis respectively are described. Finally,
some simulations are presented. |
|
Title: |
BEHAVIOR ACTIVITY TRACE METHOD - Application to Dead
Locks Detection in a Mobile Robot Navigation |
Author(s): |
Krzysztof Skrzypczyk |
Abstract: |
In the paper a novel approach to represent a history in
a mobile robot navigation is presented. The main assumptions and key
definitions of the proposed approach are discussed in this paper. An
application of the method to detect a dead lock situations that may occur
during the work of reactive navigation systems is presented. The potential
field method is used to create an algorithm that gets the robot out of the
dead-lock. Simulations that show the effectiveness of the proposed method
are also presented. |
|
Title: |
OBSERVER BASED OPTIMAL CONTROL OF SHIP ELECTRIC
PROPULSION SYSTEM |
Author(s): |
Habib Dallagi, Ali Sghaïer Tlili and Samir
Nejim |
Abstract: |
This paper describes the synthesis of a linear state
observer based optimal control of ship electric propulsion using permanent
magnet synchronous motor. The proposed approach is used for the ship speed
control by measuring the stator current and the motor speed. This strategy
of control is made possible by using a ship speed state observer. A
numerical simulation study, applied to the global system, has confirmed
the efficiency and the good performances of the proposed control
law. |
|
Title: |
MODELING AND OPTIMAL TRAJECTORY PLANNING OF A BIPED
ROBOT USING NEWTON-EULER FORMULATION |
Author(s): |
David Tlalolini, Yannick Aoustin and Christine
Chevallereau |
Abstract: |
The development of an algorithm to achieve optimal
cyclic gaits in space for a thirteen-link biped and twelve actuated joints
is proposed. The cyclic walking gait is composed of successive single
support phases and impulsive impacts with full contact between the sole of
the feet and the ground. The evolution of the joints are chosen as spline
functions. The parameters to define the spline functions are determined
using an optimization under constraints on the dynamic balance, on the
ground reactions, on the validity of impact, on the torques and on the
joints velocities. The criterion considered is represented by the integral
of the torque norm. The algorithm is tested for a biped robot whose
numerical walking results are presented. |
|
Title: |
PROBABILISTIC MAP BUILDING CONSIDERING SENSOR
VISIBILITY |
Author(s): |
Kazuma Haraguchi, Jun Miura, Nobutaka Shimada and
Yoshiaki Shirai |
Abstract: |
This paper describes a method of probabilistic obstacle
map building based on Bayesian estimation. Most active or passive obstacle
sensors observe only the most frontal objects and any objects behind them
are occluded. Since the observation of distant places includes large depth
errors, conventional methods which does not consider the sensor occlusion
often generate erroneous maps. We introduce a probabilistic observation
model which determine the visible objects. We first estimate probabilistic
visibility from the current viewpoint by a Markov chain model based on the
knowledge of the average sizes of obstacles and free areas. Then the
likelihood of the observations based on the probabilistic visibility are
estimated and then the posterior probability of each map grid are updated
by Bayesian update rule. Experimental results show that more precise map
building can be bult by this method. 1 INTRODUCTION A mobiles robot should
know its current position and obstacles and free spaces around it for
selfnavigation. That problem is known as SLAM ( Simultaneous Localization
And Mapping)(Montemerlo and Thrun, 2002; Thrun et al., 2004; Grisetti et
al., 2005). SLAM process is divided into two parts: position localization
using current observations and the current map, and the map update using
the estimated position. This paper discusses the problem of the
conventional map update methods, sensor occlusion, and proposes a novel
updating method solving it. The positions of landmarks and obstacles
should be represented on the map for navigation(Thrun, 2002b). There are
two representations available for them: 1. Feature point on the obstacle
2. Obstacle existence on small map grid. Former representation requires
feature identification and matching and the feature position is update
when new observation is available(Suppes et al., 2001). Latter
representation identifies the map grid from which the observation comes.
Since laser range sensors, ultrasonic sensors and stereo image sensors can
precisely control the direction of transmitting and receiving light or
sound, the place from which observation comes is easy to identify. Thus we
use the latter map representation here. The obstacle sensor output always
includes observation errors. For example the measurement of time of flight
of light or sound have errors caused by wave refraction, diffraction and
multi-path reflection. Stereo image sensor also has correspondence
failures of image features. These errors lead to large errors or ghost
observations. Therefore the map building should be established in a
probabilistic way based on a certain error distribution model. Here we use
a probabilistic occupancy grid map for the map representation, which
stores the obstacle existence probability in each map grid. In this
representation, the obstacle existence probability of each grid is updated
by evaluating the likelihood of obtained observation for the grid and
integrate it with its prior probability in the way of Bayesian
estimation. |
|
Title: |
A FUZZY SYSTEM FOR INTEREST VISUAL DETECTION BASED ON
SUPPORT VECTOR MACHINE |
Author(s): |
Eugenio Aguirre, Miguel García-Silvente, Rui Paúl and
Rafael Muñoz-Salinas |
Abstract: |
Despite of the advances achieved in the past years in
order to desing more natural interfaces between intelligent systems and
humans, there is still a great effort to be done. Considering a robot as
an intelligent system, determining the interest of the sourrounding people
in interacting with it is an interesting ability to achieve. That
information can be used to establish a more natural communication with
humans as well as to design more sophisticated policies for resource
assignment. This paper proposes a fuzzy system that establishes a level of
possibility about the degree of interest that people around the robot have
in interacting with it. First, a method to detect and track persons using
stereo vision is briefly explained. Once the visible people is spotted,
their interest in interacting with the robot is computed by analyzing its
position and its level of attention towards the robot. These pieces of
information are combined using fuzzy logic. The level of attention of a
person is calculated by analyzing the pose of his head that is estimated
in real-time by a view based approach using Support Vector Machines (SVM).
Although the proposed system is based only on visual information, its
modularity and the use of fuzzy logic make it easier to incorporate in the
future other sources of information to estimate with higher precision the
interest of people. At the end of the paper, some experiments are shown
that validate the proposal and future work is addressed. |
|
Title: |
HIERARCHICAL SPLINE PATH PLANNING METHOD FOR COMPLEX
ENVIRONMENTS |
Author(s): |
Martin Saska, Martin Hess and Klaus
Schilling |
Abstract: |
Path planning and obstacle avoidance algorithms are
requested for robots working in more and more complicated environments.
Standard methods usually reduce these tasks to the search of a path
composed from lines and circles or the planning is executed only with
respect to a local neighborhood of the robot. Sophisticated techniques
allow to find more natural trajectories for mobile robots, but
applications are often limited to the offline case. The novel hierarchical
method presented in this paper is able to find a long path in a huge
environment with several thousand obstacles in real time. The solution,
consisting of multiple cubic splines, is optimized by Particle Swarm
Optimization with respect to execution time and safeness. The generated
spline paths result in smooth trajectories which can be followed
effectively by nonholonomic robots. The developed algorithm was
intensively tested in various simulations and statistical results were
used to determine crucial parameters. Qualities of the method were
verified by comparing the method with a simple PSO path planning
approach. |
|
Title: |
HELPING INSTEAD OF REPLACING - Towards A Shared Task
Allocation Architecture |
Author(s): |
Foad Ghaderi and Majid Nili Ahmadabadi |
Abstract: |
Sensitivity of robots to the common mechanical and
electrical failures restricts their wide usage in real world applications.
Sometimes these failures cause the robots to loss some portion of their
capabilities, so that they cannot perform their assigned tasks.
Furthermore increases in task complexity yields situations where a single
robot can not complete a task, or in some missions none of the existing
robots can perform a task individually due to their capabilities limits.
In such cases, a team can use redundancy in the number and in the
capabilities of robots to help its members and complete the mission by
assigning a task to more than one robot. Considering requirements of
typical robotic teams during different missions, a distributed behavior
based control architecture for cooperative robots is introduced in this
paper. This architecture is based on an enhanced version of ALLIANCE, and
provides the robots the ability of performing shared tasks based on help
requests. The architecture contains a mechanism for adaptive action
selection and a communication protocol for information and task sharing
which are required for coordination of team members. The proposed
architecture is used in a box pushing mission where heterogeneous robots
push several boxes with different masses. Simulations show that the team
of robots can tolerate faults in its members and performs its mission
successfully. |
|
Title: |
MULTI AGENT-BASED ON-LINE DIAGNOSTIC SCHEME OF
SUBSTATION IED |
Author(s): |
Seong-Jeong Rim and Seung-Jae Lee |
Abstract: |
This paper presents a novel multi agent-based
diagnostic scheme of substation IED. The proposed method is the on-line
diagnostic scheme for the IEDs in IEC61850-based SA system using
multi-agents. Multi-agents detect the fault of IED installed in substation
and apply to improvement of reliability in protection and control system
of substation. These agents in the SA system embedded in the station unit,
the engineering unit, the trouble manager, backup IED and protection and
control IED as the thread form. Through the implementation and the case
studies of the proposed scheme, the availability is proven. |
|
Title: |
ELECTRO HYDRAULIC PRE-ACTUATOR MODELLING OF AN
HYDRAULIC JACK |
Author(s): |
Salazar Garcia Mahuampy, Viot Philippe and Nouillant
Michel |
Abstract: |
Before the realization of testing devices such as a
high speed (5m/s) hydraulic hexapod with a high load capacity (60 tons and
6 tons for static and dynamic operating mode), the simulation is an
essential step. Hence from softwares such as SimMecanics, we have
performed an electro hydraulic model of the servo-valve-jack part by using
parameters and recorded results with mono axis testing bench of high-speed
hydraulic jack (5m/s), which has a high loading capacity (10 tons for
static and 1 ton for dynamic operating mode). The high-speed jack is
provided by two parallel three-stage servo-valves. Each three-stages
servo-valve supplies 600L/mm. Therefore the unit allows us to obtain a
realistic model of an extrapolated hexapod from the mono axis currently
used. The aim of this article is to provide a modeling of the second and
third stage servo valves by comparison of the typical experimental reading
and the computed curves obtained from simulation. |
|
Title: |
MULTIPLE MODEL ADAPTIVE EXTENDED KALMAN FILTER FOR THE
ROBUST LOCALIZATION OF A MOBILE ROBOT |
Author(s): |
Y. Touati, Y. Amirat, Z. Djama and A. Ali
Chérif |
Abstract: |
This paper focuses on robust pose estimation for mobile
robot localization. The main idea of the approach proposed here is to
consider the localization process as a hybrid process which evolves
according to a model among a set of models with jumps between these models
according to a Markov chain. In order to improve the robustness of the
localization process, an on line adaptive estimation approach of noise
statistics (state and observation), is applied for each mode. To
demonstrate the validity of the proposed approach and to show its
effectiveness, we’ve compared it to the standard approaches. For this
purpose, simulations were carried out to analyze the performances of each
approach in various scenarios. |
|
Title: |
INTERCEPTION AND COOPERATIVE RENDEZVOUS BETWEEN
AUTONOMOUS VEHICLES |
Author(s): |
Yechiel J. Crispin and Marie-Emmanuelle
Ricour |
Abstract: |
The rendezvous problem between autonomous vehicles is
formulated as an optimal cooperative control problem with terminal
constraints. Traditionally, optimal control problems have been solved by
seeking solutions which satisfy the first order necessary conditions for
an optimum. Such an approach is based on a Hamiltonian formulation, which
leads to a difficult two-point boundary-value problem. We propose a
different approach in which the control history is found directly by a
genetic algorithm search method. The main advantage of the method is that
it does not require the development of a Hamiltonian formulation and
consequently, it eliminates the need to deal with an adjoint problem,
which usually leads to a difficult two-point boundary-value problem in
nonlinear ordinary differential equations. This method has been applied to
the solution of both interception and rendezvous problems in an underwater
environment, where the direction of the thrust and the velocity vector is
used as the control. The method is first tested on an interception
chaser-target problem where the passive target vehicle moves along a
straight line trajectory at constant speed. We then treat a cooperative
rendezvous problem between two active autonomous vehicles. We take into
account the effects of gravity, thrust and viscous drag and treat the
rendezvous location as a terminal constraint. |