Fixed-time anti-windup sliding-mode-tracking controller for piezoelectric motion stages

Abstract

This study addressed the practical high-precision tracking control problem of piezoelectric motion stages (PMS) by designing an anti-windup compensator and employing hysteresis modeling to achieve an effective tracking controller for a PMS with input saturation and hysteresis nonlinearity. First, a novel anti-windup compensator with fixed-time convergence characteristics is proposed and rigorously proven. The fixed-time anti-windup compensator (FTAWC) compensates for the tracking error generated during control input saturation and converges quickly when exiting input saturation, thereby ensuring excellent tracking performance. Subsequently, a fixed-time anti-windup sliding-mode controller (FTAWSMC) is established based on the proposed FTAWC. An analysis and proof are provided to demonstrate the convergence of the tracking error under the FTAWSMC. The controlled PMS is then precisely identified using the Bouc–Wen hysteresis model and particle swarm optimization method. Comparative experimental results show the superior tracking and anti-windup performance of the FTAWSMC, demonstrating significant improvements in the desaturation speed and overall tracking accuracy compared with those of conventional methods. Thus, the developed controller is suitable for applications where high-precision tracking control of PMS systems is required.