This article describes the possible structure of two fuzzy-controllers. The first controller steers the rear axle of a four-wheel steered vehicle with the result of a constant self steering behaviour over the entire possible range of lateral acceleration. The second controller steers the rear axle of a four-wheel steered vehicle, so that the sideslip angle as well as the sideslip angle velocity are compensated. Furthermore it is shown that for both cases the transient driving behaviour is improved compared to a conventional steered vehicle. The fundamentals of fuzzy set theory as well as of fuzzy logic will be briefly explained. The investigation is based on the simulation of a non-linear two track two track simulation model with non-linear tire characteristics. The software package "Fuzzy Control Manager" (FCM) was used in order to structure the fuzzy-controllers. (A)
Abstract