Advanced control design for a vehicle steer-by-wire system by using adaptive fast nonsingular terminal sliding mode

摘要

To obtain accurate and robust steering performance, Steer-by-Wire (SbW) equipped vehicles require effective steering control schemes. Therefore, an adaptive fast nonsingular terminal sliding mode (AFNTSM) controller is proposed for a SbW system in this paper, in which an adaptive estimation law and a fast nonsingular terminal sliding mode (FNTSM) control scheme are combined together. First, a mathematical model to identify the dynamics of the SbW system is presented, where the friction-related forces and the self-aligning torque are regarded as external disturbances. Second, the AFNTSM control design is described, the stability of the control system is verified in the sense of Lyapunov in detail. Finally, experimental results are shown, which demonstrates the superiority of the designed AFNTSM controller in comparison with an FNTSM controller and a conventional sliding mode controller.