Design requirements

Initially, the system needs to be assessed to determine what level of safety properties it should have. Traditionally, the automotive industry classified systems as being safety-related or non-safety-related. Most other industries now use a four-level classification of safety requirements, commonly known as the safety integrity level (SIL) of a system. The automotive industry has adopted a similar scheme. SILs are allocated to systems and functions by following a safety analysis process. The safety integrity requirements are then used to select the appropriate development process. Ongoing safety analysis during design and implementation is used to confirm that the product is being developed according to its safety integrity requirements.Safety analyses should be carried out using a multi-disciplinary team including application domain experts. This ensures that the results of the safety analysis take account of automotive-specific issues and requirements. For example, a safety analysis on a brake-by-wire system should include experts in automotive braking systems and vehicle dynamics.

Conclusion

Drive-by-wire systems offer many opportunities to improve the driving experience whilst producing vehicles that are safer and more reliable. In enhancing traditional automotive engineering practices with best practice gained from other sectors, the specific needs of the industry in areas such as packaging and cost must be respected. Changes to the regulatory framework are also required to permit the introduction and approval of such systems. In a nutshell, a change from mechanical to electronic systems in modern automobile engineering signifies a huge leap in human effort to produce more user- friendly automobile and reduce the amount of road fatality.

Authored by: Dr David Ward, MIRA and Richard Woodgate, Aerosystems International.

David Ward read Natural Sciences (Physics and Theoretical Physics) at Churchill College, Cambridge, from which he received his BA (Hons) and MA. He was then employed as a Research Assistant in the Department of Electrical and Electronic Engineering at the University of Nottingham, from which he received his PhD. In 1991 he joined MIRA where he is Head of Research in the Electrical Group.
Richard Woodgate, CEng MIEE MAPM, read Electrical Sciences at Caius College, Cambridge, receiving his BA in 1980, and has worked extensively in the defence and aerospace industries. In 1989 he joined Aerosystems International where he is responsible for the company's business processes and provides business process and engineering consultancy. Richard is a member of the BAE Systems Software Engineering Council and has been working with MIRA as part of a venture to transfer aerospace techniques into the automotive sector. He is a Chartered Engineer.

Summarized by:
Low Kok Kiat
Faculty of Electrical Eng.
University of Technology Malaysia.