High-Gain Observer-Based Super-Twisting Sliding Mode Control for Car Driving Simulator Systems

This paper presents an output feedback control method accompanied by a velocity observer for the trajectory tracking problem of a 4-DOF car driving simulator system (CDS) in the absence of velocity measurement. In practice, because the velocity sensors are normally expensive and contaminated with disturbance, the assumption of precisely acquiring velocity signals is infeasible in some cases. Besides, the dynamic model of the system exhibits a highly nonlinear property and depends significantly on the value of velocity signals. Therefore, the super-twisting sliding mode controller is designed to ensure high tracking performance and attenuate the chattering phenomenon which usually occurs in traditional approaches due to the switch function. In addition, the high-gain observer is employed to estimate the velocity information for controller construction. The stability of the closed-loop system is demonstrated through the Lyapunov theory. Simulation results are taken into implementation to illustrate the effectiveness and validity of the proposed method.