Tacking Control of Piezoelectric Stick-Slip Actuator Based on Integral Terminal Sliding Mode Strategy

Piezoelectric stick-slip actuators have influences such as model uncertainty, nonlinear factors and external disturbances that reduce control accuracy. In this paper, an integral terminal sliding mode controller is proposed for the precise positioning control of piezoelectric stick-slip actuators. The method can achieve convergence in finite time and serve to reduce the jitter steady-state error. The convergence law using a combination of power convergence law and exponential convergence law can reach the sliding mode surface at a faster rate. The stability of the control method is verified by the Lyapunov method. Finally, the effectiveness of the modified control method is verified by simulation. The results show that the control method improves the dynamic performance and stability accuracy of the system more than the traditional sliding mode controller.