Sliding mode control with sigmoid function for the motion tracking control of the piezo-actuated stages

A Bouc–Wen model is presented and identified based on the bat-inspired algorithm to describe the hysteresis of the piezo-actuated stage. Based on the established Bouc–Wen model, a sliding mode controller is proposed to suppress the hysteresis non-linearity of the piezo-actuated stages. In order to solve the buffeting problem in the process of control, the sign function is replaced by the sigmoid function. Experiment is performed to validate the effectiveness of the proposed sliding mode controller, and the results show that the maximum error of the motion tracking control of the piezo-actuated stage is 0.3264 μm.