Adaptive Output Feedback Dynamic Surface Sliding Mode Control for a Class of Uncertain Nonlinear System with Unknown Actuator Hysteresis

Abstract

In this paper, a RBFNNs based output feedback adaptive dynamic surface sliding mode control (DSSMC) method is proposed for a class of uncertain nonlinear system with actuator hysteresis. The main contributions are listed as follows: 1) by comprehensively considering the mutual influence between the tracking errors of each subsystem, a sliding mode dynamic surface is defined. Also, the recursive method is used to design the control law, which reduces the computational burden; 2) by introducing the PI hysteresis model and the state observer, the hysteresis behavior exists in the actuators can be mitigated when only the system output is measurable; 3) by using RBFNNs, the unknown uncertainties and external disturbances can be estimated. It is proved by Lyapunov method that all signals in the closed-loop system are semi-globally uniformly bounded. The simulation results verify the effectiveness of the proposed control method.