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By-wire systems have been established for several years in the area of aircraft constructions. There is the visible trend to realize by-wire applications without mechanical or hydraulic backup systems in vehicles. The required electronic systems must evidently be available and safe. This paper addresses a new automotive architecture approach using the time-triggered fault-tolerant TTP protocol that has been designed for class C safety related control applications, like brake-by-wire or steer-by-wire, due to the SAE classification [1]. As an example we present this approach within a brake-by-wire research car (case study) without mechanical backup. The intention of this architecture is to tolerate one arbitrary fault - excepting faults of actuators - without any effects of the brake performance. For this purpose we use redundancy in communication (TTP) and electric components like sensors, actuators and power supply.

This paper presents an approach to the design of automotive applications based on the client/server architecture, which has been well established in office automation. The basic client/server model is first discussed in the context of automotive requirements. This new function oriented approach is then compared to the previous, device oriented approach. After the introduction of basic components the communication mechanism is discussed with regard to the fundamental procedures, data representation and protocol implementation. Its usage is then explained by an example. Finally, after presenting the results of this study, there is an outlook to future work as well as to possible collaboration with others partners in order to achieve further standardization.

The design of automotive electronics is a highly cooperative, distributed process between car manufactures and suppliers. Due to significant increase of quality, cost, and time to market demands, several initiatives have been founded over the last years to address the increasing demand for standardization both for automotive electronics and vehicle based software. The German MSR consortium has concentrated on design tools and information exchange between manufacturers and suppliers, whereas the OSEK/VDX consortium has concentrated on the establishment of basic software components for open system architectures. To address future demands, these activities have to be consolidated and complemented by initiatives addressing the systematic improvement of the concurrent design processes as well as the appropriate qualification of engineering personnel.

Introduction of an array of new electrical and electronic features into future vehicles is generating vehicle electrical power requirements that exceed the capabilities of today's 14 volt electrical systems. In the near term (5 to 10 years), the existing 14V system will be marginally capable of supporting the expected additional loads with escalating costs for the associated charging system. However, significant increases in vehicle functional content are expected as future requirements to meet longer-term (beyond 10 years) needs in the areas of emission control, fuel economy, safety, and passenger comfort. A higher voltage electrical system will be required to meet these future requirements. This paper explores the functional needs that will mandate a higher voltage system and the benefits derivable from its implementation.

Blendings of methanol and diesel fuel can only be produced in form of emulsions. The stability of those emulsions strongly depends on the concentration of surface active agents. It is shown that observed changes in mixture formation of emulsions in comparison to pure diesel fuel conditions can be explained by a theory of spontaneous evaporation. Several feasible droplet models are discussed. Emulsion droplets evaporate spontaneously if the droplet temperature exceeds the superheating limit of the disperse phase. The superheating limit is only exceeded at the outer zone of the injection jet.