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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.

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.