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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.

Extensive crash sled testing and analysis has recently led to the development of a new HANS prototypes for use in FIA F1. The performance of HANS prototypes has been studied with various conditions of HANS design geometry and impact direction. The new HANS prototypes have been found to substantially reduce injurious motions and forces of the head and neck, and the new HANS is lighter, more compact, and performs better than the currently available HANS. Use of HANS by FIA F1 drivers has been initiated.

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 experience which has been gained in more than ten years with vehicles for the U.S.A. and Japan forms the basis of the catalytic converter systems for application in Europe. We are talking about the improvement of the mechanical and chemical endurance of catalytic converters and oxygen sensors. Special attention is paid to various substrate materials (e.g. steel) and coatings concerning their properties with regard to high-temperature stability and power loss. Moreover we are dealing with the increased application of electronics in the engine. The paper mainly refers to the Mercedes-Benz 190 E 2.3-16. This vehicle is used as an example to show the development of an emission concept for European requirements.

Daimler-Benz considers safety belts as the fundamental and essential restraining system. The company began offering a Supplemental Restraint System option consisting of a driver airbag system and an emergency tensioning belt retractor for the passenger in December 1980. The functional reliability of the system has proven satisfactory.

Among many tasks of car development, safety, economy, environmental benefits and convenience, safety should have a high priority. One of the main goals is the reduction of the number of accidents. Environment and situation recognition by autonomous vehicle-electronic systems can contribute to the recognition of problems together with information to the driver or direct intervention in the car's behaviour. This paper describes some techniques for environment recognition, the status of a present project, and the goals of some PROMETHEUS (Program for a European Traffic with Highest Efficiency and Unprecedented Safety) projects.

The ultimate goal of drive-line management is low fuel consumption as well as providing the highest possible driving performance within the bounds of good driving safety. This can only be achieved by shifting the operating region on the performance diagram. In order to do this the technical characteristics of the drive-line components must be taken into account. The development of drive-line optimization can be separated into two phases. In the first phase the driver is partially or entirely integrated into the control circuit via external visual and acoustic feedback inputs. In the second phase automatic controls take-over the drive-line management without putting stress on the driver so that the vehicle in effect controls itself.

Information on the driving stability can be obtained in the form of oversteer or understeer tendencies and acceleration limits on a circular path. Up to now the calculations have only been made on an ideal, even roadway. Significant dynamic characteristics, such as the tuning of the shock absorbers, which also play a role in evaluating the stability of a vehicle in a driving test, are thereby not included in the calculations. In this paper the unevenness of the roadway is taken into consideration in calculating steady state cornering tests. Different vehicle models can be evaluated in regard to their handling or active safety with the aid of the driver's steering actions required to keep the car on course.

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.

This report deals with the development and use of the Daimler-Benz Isohuman Simulation Model for the mathematical simulation of dummy behaviour in an impact environment. Designated ISM, this computer program package is capable of handling both automobile occupant and pedestrian kinematics. Daimler-Benz safety engineers use the ISM to evaluate new safety designs before performing actual laboratory tests. The ISM code uses the theoretical algorithm of Prof. Wittenburg. The dummy is represented by 11 rigid body elements. Realistic and accurate simulations are assured by the fact that a considerable number of functional and sophisticated algorithms were developed to involve the different interactions of dummy-to-belt or dummy-to-vehicle. In particular, considerable work is being done to introduce a more precise and realistic dummy and vehicle geometry.