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The two major problems of diesel emission control are the reduction of nitrogen oxides and particulates. This paper describes experimental investigations to achieve both a separation of soot particles as well as a catalytic NOx reduction with hydrocarbons under lean diesel exhaust gas conditions. For that purpose a diesel particle trap is coated with a catalyst based on a Pt containing zeolite. Preliminary studies have been performed on the catalytic NOx reduction to evaluate the efficiency of a Pt/zeolite system as well as to establish the impact of operation conditions on the catalyst performance. The activity of the prepared samples (catalytic coating on particle trap) has been determined under model gas test conditions. Much attention has been focussed on the steady-state kinetics of the surface processes. Another aspect considered is the N2O formation which can be reduced, when alkali-earth or rare-earth oxides are added to the catalyst system.

An adsorber system for reducing cold start hydrocarbon (HC) emissions has been developed combining existing catalyst technologies with a zeolite-based HC adsorber. The series flow in-line concept offers a passive and simplified alternative to other technologies by incorporating one additional adsorber substrate into existing converters without any additional valving, purging lines, or special substrates. This contribution describes the current development status of hydrocarbon adsorber aftertreatment technologies. We report results obtained with a variety of adsorber, start-up, and underfloor catalyst system combinations. In each case, it was possible to achieve HC emission levels in compliance with the ULEV standards, and in the best cases, demonstrating HC emissions substantially below the legislated standard.

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.

The awareness concerning environmental issues and the economical need for fuel savings leads to the introduction of new, highly efficient Diesel engines for passenger cars. An engine with common rail injection system could meet this target and, with the help of an advanced diesel exhaust aftertreatment system also fulfilled the new legislative emission regulations. Besides the efficient oxidation of carbon monoxide (CO), hydrocarbons (HC) and diesel particulates, such a system also requires a moderate reduction efficiency for nitrogen oxides (NOx) under excess oxygen conditions. The present paper illustrates the further progress in catalytic NOx-reduction under excess of oxygen by hydrocarbon enrichment using the common rail injection system.

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.

One possibility to improve the fuel economy of SI-engines is to run the engine with a lean air-fuel-ratio (AFR). Hydrocarbon and carbon monoxide after-treatment has been proven under lean operation, but NOx-control remains a challenge to catalyst and car manufacturers. One strategy that is being considered is to run the engine lean with occasional operation at stoichiometry. This would be in conjunction with a three-way-catalyst (TWC) to achieve stoichiometric conversion of the three main pollutants in the normal way and a NOx trap. The NOx trap stores NOx under lean operation to be released and reduced under rich conditions. The trap also functions as a TWC and has good HC and CO conversion at both lean and stoichiometric AFR's. Under lean conditions NO is oxidised to NO2 on Pt which is then adsorbed on an oxide surface. Typical adsorbent materials include oxides of potassium, calcium, zirconium, strontium, lanthanum, cerium and barium.

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.

The use of pistons made of fine grain carbon was investigated in a spark-ignition engine within a European Community funded research project (TPRO-CT92-0008). Pistons were designed and manufactured and then tested in a single cylinder engine. Due to the carbon material's lower coefficient of thermal expansion the top land clearance between piston and cylinder can be reduced by a factor of three in comparison to standard aluminium designs. Under steady-state part-load operating conditions the emission of unburned hydrocarbons can be reduced by more than 15% compared to aluminium pistons, without significant penalties in NOx-emissions. Simultaneously, a small improvement in fuel economy of about 2% is observed. At full-load blow-by leakage flow is reduced by more than 50%. The piston crown temperature is about 30°C higher with the carbon piston than with the standard aluminium piston, due to the lower thermal conductivity of the carbon material.