Elmar Dilger

Fault Tolerant Mechatronics

Modern cars exhibit a variety of new functionalitiesconcerning engine management, safety, vehicle dynamicscontrol as well as comfort and convenience. Safetyfeatures like airbags, antilock braking systems (ABS),anti-skid systems, belt tensioners or the electronic stabilityprogram (ESP) are standard fittings of present daycar models and in some cases even stipulated by legislation.These safety systems have led to an increasedavoidance of accidents by actively affecting vehicle dynamicsand to a mitigation of the consequences of accidentson the driver and passengers by innovative restraintsystems.As a rule these systems are mechatronic systems.Mechatronic systems [Mechatronic Systems] today derive their functionalityby an interlocked interaction of mechanics, electronicsand information technology. Their deployment in thesafety-relevant environment requires fault tolerance.Fault tolerant mechatronics is based on redundancy,which must be supervised and tested permanently.Reliability of sensor and actuator technology is essentialfor future motor vehicle systems. Operability andreliability are to be achieved by suitable on-board andon-line test methods. Exemplarily this is shown forfuture X-by-Wire applications.

Fault tolerant mechatronics [automotive applications]

Modern cars exhibit a variety of new functionalities concerning engine management, safety, vehicle dynamics control as well as comfort and convenience. Safety features like airbags, antilock braking systems (ABS), anti-skid systems, belt tensioners or the electronic stability program (ESP) are standard fittings of present day car models and in some cases even stipulated by legislation. These safety systems have led to an increased avoidance of accidents by actively affecting vehicle dynamics and to a mitigation of the consequences of accidents on the driver and passengers by innovative restraint systems. As a rule these systems are mechatronic systems. Mechatronic systems today derive their functionality by an interlocked interaction of mechanics, electronics and information technology. Their deployment in the safety-relevant environment requires fault tolerance. Fault tolerant mechatronics is based on redundancy, which must be supervised and tested permanently. Reliability of sensor and actuator technology is essential for future motor vehicle systems. Operability and reliability are to be achieved by suitable on-board and on-line test methods. Exemplarily this is shown for future X-by-wire applications.

A new code with reduced EMI and partial EC possibilities

The data exchange rates in automotive applications for communication, supervising and safety purposes is rising dramatically. Transmitting raw data beyond rates of some Mbaud via unshielded lines can cause intolerable EMI (electromagnetic interference) effects but shielding is very expensive and not acceptable for high volume products in automotive applications. The proposed code is suitable for arbitrary bus systems. It allows even increment and arbitration operations on passing message frames, as it is necessary for the MOST protocol. The code can ease transmissions on an electrical physical layer without the need for shielding. It is d.c. balanced and shows favorable EMI properties. Furthermore, special code properties facilitate error detection and correction mechanisms.