Tracking control method of piezoelectric actuator for compensating hysteresis and creep

Piezoelectric actuators are a class of smart transducers with a great potential for many micro-nanometer motion applications. A major challenge for the piezoelectric actuators exists in the control of such ultra-precision motions, which are often seriously influenced by the intrinsic behaviors of piezoelectric material like non-linearity, hysteresis and creep. Based on a proposed hysteresis-creep model, this paper presents a new tracking control algorithm to improve the positioning and tracking performances of a linear multilayer piezoelectric actuator. In this algorithm, a feedforward inverse controller is designed according to the hysteresis and creep model of piezoelectric actuator. The method of inverse model of hysteresis-creep is explained detailedly. The tracking control method is applied to an experimental piezoelectric actuator system to demonstrate its efficacy, and the experimental results demonstrate that both hysteresis and creep phenomena are effectively canceled and accurate tracking of a reference trajectory is achieved in open-loop operation.