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Through the decline in prices of semiconductor technology, automotive applications have boosted and can be characterized in technological leaps, the first example was the introduction of ABS in 1978 leading on to the equipment with ESC in 1995. In the next technological leap forward, the cross-linking of today's many and varied, largely stand-alone chassis control units, is envisaged. This technological leap forward in networking, the functional integration of brakes and steering, is described by the ESC II system.

This paper describes an approach of how to control the wheel slip of a vehicle using brake-by-wire actuators. The advantage of brake-by-wire actuators - such as the electro-hydraulic (EHB) and the electro-mechanical brake (EMB) - is that the caliper pressure or the clamping force, respectively, are known. It will be shown by measurement results that the wheels of a research vehicle equipped with an EHB system and the new control approach can be kept at any desired wheel slip on different surfaces, i.e. ice, snow, and dry asphalt.

In the scope of a research collaboration, Continental Teves (formerly ITT Automotive Europe) and Darmstadt University of Technology are developing control strategies for a low-cost Brake-by-Wire system, using no clamping-force or brake-torque sensor as feedback [1]. However, since there is a wide range of variation in the efficiency of the gear units used in electromechanical brakes, this becomes a demanding task. The paper first describes the assembly and operation of Continental Teves' third generation brake actuator, which is still operated using an integrated clamping force sensor [2]. It introduces the development environment of Darmstadt University of Technology, consisting of a brake test stand, a complex brake actuator model, and a simplified brake actuator model.

In the scope of a research collaboration, ITT Automotive Europe and Darmstadt University of Technology are developing control strategies for a low-cost Brake-by-Wire system. However, since there is a wide range of variation in the efficiency of the gear units used in electromechanical brakes, this becomes a demanding task. The paper first describes the assembly and operation of ITT's early generation brake actuator. It introduces a model of the electromechanical brake with its structure and subsystems as a major tool in the development process. A detailed analysis of the signals, already available from the brake and the vehicle, is discussed for their advantages and disadvantages with regard to a possible use in the controller design. Different approaches for clamping-force, peripheral-force and brake-torque sensing are compared. An integrated clamping force sensor for feedback control of prototype actuators was developed.

This paper deals with the supervision of the Diesel injection process. A new method to analyse the injection quality is presented which is based on the acquisition and evaluation of cylinder pressure signals. In this novel approach, a reconstructed “motored” pressure is substracted from the fired pressure signal resulting in independence from a possible sensor offset and a contrast amplification. To describe the shape of the difference pressure, features like the center of gravity or the secant length at certain pressure values are introduced. These numbers can be used for supervison of the injection pump (backward diagnosis) as well as for driving the engine at operating points with low exhaust production (feedforward control). The presented concept is supported by simulations and real-time measurements obtained from a swirl chamber Turbo Diesel stock car engine (4 cylinders, 1600 ccm).

The wheel speed and the slip are important signals for many modern automotive control systems. The performance of these systems strongly depends on the quality of the evaluated wheel speed and the slip. However, during car motion, especially during acceleration or braking, deflections of the flexibly mounted wheel suspension and of the tire disturb the measurement or rather the determination of these signals. In this paper an approach to increase the quality of the evaluated wheel-speed signal and the slip signal by considering these influences is introduced. The method considers the longitudinal motion of the wheel center, the tangential motion or rather the oscillations of the belt, the changing of the dynamic tire radius and the disturbances due to the angular motion of the wheel-speed sensor. To obtain the required kinematic values for the compensation, a mathematical model of the wheel suspension and of the tire is developed.