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Present and future assisting systems are meant to support the driver in coping with the difficulties of driving. The design of the system properties and their limits helps to influence on the road-driving behavior directly and through teach-back effects. On the other hand, there is a potential risk of negative effects on the safety due to a division of tasks between the driver and the technical system. Bearing this in mind, the Automotive Engineering Department and the Department of Ergonomics of Darmstadt University of Technology were engaged by BMW AG to investigate the distance behavior of vehicles with and without ACC (Adaptive Cruise Control) which is used to control the speed and distance maintained to vehicles ahead and turning into the traffic. This trial was made with the aim of a representative and objective investigation of the behavior of the total system of driver-vehicle-environment in road traffic.

Future on-board vehicle control systems can be further improved through new types of mechatronic systems. In particular, these systems'' capacities for interaction enhance safety, comfort and economic viability. The Automotive Engineering Department (fzd) of Darmstadt University of Technology is engaged in research of the mechatronic vehicle corner, which consists of three subsystems: sensor tire, electrically actuated wheel brake and smart suspension. By intercommunication of these three systems, the brake controller receives direct, fast and permanent information about dynamic events in the tire contact area provided by the tire sensor as valuable control input. This allows to control operation conditions of each wheel brake. The information provided by the tire sensor for example helps to distinguish between straightline driving and cornering as well as to determine μ-split conditions.

In future, there will be increasing demand for mobility and transportation especially in the newly industrialized countries where about half of the world''s population lives. This will enormously increase the number of vehicles in operation. The fact of such development taking place in the economically poorest countries of the world is alarming because these will not be able to apply strict emission and safety legislation as is practiced in the highly industrialized nations. Renewable energy must be developed and used to reduce exhaust emission even though fossil fuels will be available for decades in the future. Besides further reduction of required energy and increase of efficiency, intelligent traffic management systems will play a major role in tackling the challenges put by our demands for individual mobility.

In comparison to other vehicles motorcycles have very special driving characteristics, so the typical use of motorcycles is clearly distinct from the use of passenger cars. At Darmstadt University the riding behavior of motorcyclists has been experimentally investigated [2, 3, 4, 5], especially in order to determine their exhaust and noise emissions in real traffic. The results and the essential differences between motorcycles and cars should be considered in the discussion of testing methods and limiting values, e.g., for exhaust and noise emissions of two-wheelers. This paper presents a comparison between the typical driving performance of motorcycles and passenger cars and contains results of motorcycle exhaust and noise emission measurements in real traffic and in statutory tests. The current legal measuring standards are found not to represent the reality of motorcycle traffic in a sufficient manner.

With the view to many new opportunities with actuation devices of oncoming Brake-by-wire-systems, the active driving safety could be increased by means of vehicle braking dynamics on the one hand and by means of optimization of the driving conditions during braking on the other hand. This is a strong focus of the brake-pedal and Brake-by-wire research at the Department of Automotive Engineering at Darmstadt University of Technology (fzd) and the ‘Sonderforschungsbereich’ IMES (Mechatronics for Mechanical Engineering) of the ‘Deutsche Forschungsgemeinschaft’ (DFG) with task B6. To study the brake pedal feel, a new research vehicle focusing on an adjustable brake pedal has been developed. In view of the wide range of influences on brake pedal feel, this car allows systematic research of the brake system's man/machine interface.

Since 1989 the Automotive Engineering Department of Darmstadt University of Technology (fzd) has carried out measurements of tire tread deformations through the use of sensors which are integrated into the tire. With these tire sensors fzd has achieved the possibility to qualitatively and quantitatively measure forces acting on the tire, especially local slip effects, which are the basis for friction detection. To investigate local slip fzd designed a completely new measuring device. Utilization of available tire/road friction and local slip events were measured in a specially equipped test car. This paper describes the Darmstadt Tire Sensor, the theoretical vehicle system, the methods to study tire sensor behaviour as well as the results achieved so far.

On the basis of three examples of Darmstadt University research some problems and future tasks of designing the man-vehicle-interface are described. The driving behavior of passenger car drivers in real traffic is analyzed and possibilities to protect the driver in critical driving situations are derived. A new device for measuring the coupling forces between motorcycles and drivers which are essential to motorcycle dynamics is presented. First results with this are discussed. Finally, research into emergency braking is described. The research work was jointly conducted by the Department of Automotive Engineering (fzd) and the Institute of Ergonomics (IAD) of the Technical University of Darmstadt.

Tyre/road-friction determines which driving manoeuvres are physically possible and is therefore of utmost importance for vehicle safety. At the Department of Automotive Engineering (fzd, Head: Prof. Dr.-Ing. B. Breuer) of Darmstadt University (THD) research on the on-board measurement of tyre/road friction was started 1988 and has since then been funded by Deutsche Forschungs-Gemeinschaft (DFG) and within the European research-project PROMETHEUS. Methods and instruments described in this paper represent its present state. Two different methods of friction detection are proposed: one computes a μ-slip-curve from contactless measurements of the road surface, the other derives friction from signals gained inside the tyre. Beside several influences on the friction level, which are measured in their entirety on real roads under natural conditions, some effects of local tyre behaviour are discussed.

Brake force distribution to the front and rear wheel is normally left to the drivers of motorcycles; some production vehicles have so called combined or integrated brakes where brake force distribution is predetermined by design. Research work on the braking behaviour of motorcycles was done by the authors with two 1000 cc-motorcycles, which were equipped with 2 different ABS (mechanical, /, electronic) and subjected to driving experiments on various road surfaces at different speeds in straight ahead and curve braking. Braking performance and driving stability was investigated for normal and emergency braking with both standard and combined brakes with and without ABS. The results demonstrate, that braking performance and safety is best with ABS in a combined-brake-vehicle. Curve braking is difficult and complex in any case and needs more research which is in progress in Darmstadt right now.

This paper deals with the development of system-vehicles-characterized by front-mounted safety cabins, front and rear hydraulic three-point hitches with automatic couplings for implements, and centrally mounted tanks or containers-for farm and industry. Technical configuration of a range of four vehicles with an engine output form 37,5 kW-DIN (51 hp-DIN) to 174 kW-DIN (236 hp-DIN) is explained. Particular attention is paid to problems concerning an automatic hydrostatic transmission. Farm and industrial applications of these vehicles are illustrated.