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In the past there has been a concentration on performing LCAs of car components. Based on the increasing experience and know-how gained in the past by performing LCAs of car components truck designers get the chance to make a statement about the ecological impact of each alternative. The most significant difference between LCAs of car and truck components is the use phase. This paper describes a Life-Cycle-Assessment (LCA) of different air deflection systems made of composite materials. The actually used system is produced by Resin Transfer Molding (RTM) while a possible alternative could be made out of Sheet Molding Compound (SMC). The calculations have shown that there exists a potential to improve the ecological profiles of composite components by replacing glass fibers with natural fibers.

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.

During the design, evaluation and optimization process of automotive brake systems brake torque measurements are often crucial. Known brake torque sensors lead to differences in terms of mass, inertia, stiffness and brake cooling compared to a vehicle without measurement equipment. In this contribution a new brake torque sensor is described which proved to be superior to known systems. Either the hub itself is turned into the sensing element or is replaced by a sensing element. Thus mass, inertia, stiffness and cooling conditions are nearly unchanged. A modification of this sensor allows measurement of residual brake torques in a low range (20....50 Nm) with high sensivity and features at the same time a high range (up to 2.000 Nm) with lower sensivity. The application of the sensor in a study to lower energy loss caused by residual brake friction in a passenger car is described.

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 Series Hybrid project is described concerning the scenario, technical data of vehicle and components and operating strategy. The two prototype cars offer an attractive driveability. Test results show high potential on emission reduction without increasing the consumption. The question is frequently asked as to which concept is the best. It is not so easy to answer this question. It can only mean: which concept is the best for a given application? In our opinion parallel hybrids make sense where a vehicle is required to be driven both conventionally and with electric drive only, e.g. conurbation scenario, driving and delivering in sensitive areas. In terms of weight, packaging and costs, a realization is much easier if electric-only propulsion is only required for a limited performance and range.

The active safety of tractor / trailer-combinations plays an important role in regard to traffic safety in general. For improving the active safety of tractor / trailer-combinations, it is necessary to investigate the interactions between the towing vehicle and the trailer during braking maneuvers. This paper describes the ECE-regulations for the braking force distributions of tractor/full trailer- and tractor / semitrailer-combinations. The influence of different layouts of the braking systems within these regulations on the coupling forces between tractor and trailer and the driving performance of the units during braking is investigated. The dynamical behaviour of a tractor/full-trailer-combination and a tractor / semitrailer-combination are both discussed with the aid of simulations of the ISO-standard testing procedures “Braking in a turn” and “Braking straight ahead”.

Absolute two-dimensional concentration distributions of nitric oxide have been measured in a fully transparent square piston engine with planar laser induced fluorescence. A calibration procedure was used to obtain absolute NO concentrations. The NO formation was studied in the propane/air fueled engine as a function of air/fuel ratio, crank angle and load. Simultaneous measurements of NO distributions by LIF and temperature fields via Rayleigh scattering allowed to study the correlation of NO formation and temperature. It was found that the measured NO was mainly formed via the Zeldovich mechanism.

The Daimler-Benz Driving Simulator is a tool for research and development. It was put into operation 1984/85 and was enhanced since that time in many details, having gained a lot of experience with its use in many different applications. During a main modernization from autumn '93 until summer '94, the driving dynamics computer system as well as the visual system have been exchanged and the hydraulic motion system has been extended in lateral direction for improving motion simulation quality.

The importance of autonomous vehicle operation to satisfy future safety and productivity requirements is emphasized by the current National plans for IVHS and AHS development and deployment. Daimler-Benz Research, in cooperation with Freightliner Corporation, is developing a research vehicle VECTOR (Vision Enhanced/Controlled Truck for Operational Research) which currently is undergoing testing of a vision-based control system for lateral guidance. This effort is building on experience from prior Daimler-Benz and PROMETHEUS projects, including the test vehicles VITA (VIsion Technology Application) and OSCAR (Optically Steered CAR). The paper describes this work and future expansion plans to incorporate longitudinal control systems in VECTOR.

Daimler-Benz have developed an automatically/electronically controlled traction system, the 4MATIC. Great store has been set by active safety. This paper deals with the problems involved in 4-Wheel drive and analyzes the reasons which led to the 4MATIC concept. Depending on the conditions encountered, the drive components engage automatically one after the other in the sequence front-wheel drive - interaxle differential lock - rear axle differential lock. The engagement, and thus the approaching limits of driving dynamics, is indicated to the driver by an indicator lamp so that he can adjust to the deteriorated conditions in time. A further important advantage of this system is the automatic disengagement of the differential locks when braking so that the anti-lock braking remains fully effective.

The driving simulator is a computer-controlled tool to study the interface between driver and vehicle response under simulated traffic conditions. It permits a controllable, reproducible and cost-effective study of vehicle parameters up to the limits of active safety under non-dangerous conditions. It also permits driver participation in judging vehicle handling characteristics, and in evaluating the ‘feel’ of the steering, suspension, braking, and drive train, including the driver's environment, beginning with the initial vehicle design stages. The paper will describe fully the concept, design and planned activities as well as report on the new possibilities of using the driving simulator as a research and development tool.

The main noise sources of a diesel passenger car are determined and possible noise level reductions are assessed. Primary damping measures such as influencing it by means of modifying the combustion itself as well as secondary measures such as encapsulation are described. A vehicle-supported encapsulation of the engine utilizing parts of the body is discussed in more detail. A research vehicle was built. A description of design function, and practical realization of such a vehicle-supported encapsulation including the necessary development of a new cooling system is given. Finally, the maximum possible reduction of the external noise levels using this design as well as the problems connected with encapsulation - such as the resulting increase in internal vehicle noise and vehicle weight, reduced ground clearance and maintenance accessibility - are reported and critically evaluated.