Performance enhancement of a sliding mode wheel slip controller by the yaw moment control

Abstract

A sliding mode wheel slip controller is the subject of this paper. The proposed wheel slip controller was based on a quarter-car model and a friction force observer was applied to ensure the robustness of the controller with respect to the estimation error. It was applied to a non-linear full vehicle model. This controller showed good longitudinal performance in tracking reference slip ratio regardless of modelling errors and disturbances. However, when cornering was combined with braking or there was a yaw moment disturbance due to a μ-split road, it was difficult to achieve the desired performance using this controller. In this case, lateral motion must be considered in maintaining the control of the vehicle. A yaw moment control method using the modified reference yaw rate was investigated. The effectiveness of this control theory was verified through simulations of emergency manoeuvres using a developed non-linear full vehicle Simulink model.