Backstepping adaptive sliding mode control for automatic steering of intelligent vehicles

A novel approach which integrates the backstepping technique and adaptive sliding mode control is proposed for the automatic steering control of autonomously driving intelligent vehicles. By taking account into the vehicle lateral dynamics and vehicle-road kinematics relationship, the error-based vehicle-road dynamic model for path tracking is presented. Then, a feedforward and feedback control scheme is proposed. The feedforward term is derived from steady response of the vehicle lateral dynamics, and the feedback term is designed based on sliding mode and backstepping techniques. In addition, the adaptive law for estimating uncertainties is designed to improve path following accuracy. The effect of control parameters to the automatic steering system is described as well. Simulation results are presented to illustrate the effectiveness of the proposed control algorithm.