Design and Implementation of a Feedforward Feedback Controller for a Piezoelectric Actuator

This paper presents a feedforward-feedback framework to control a piezoelectric-actuated positioning system. In the proposed control structure, the inverse Bouc-Wen model is used as the feedforward controller to compensate hysteresis; and a PI controller as feedback compensator. To obtain the parameters of the inverse Bouc-Wen model, a recursive identification method is applied. Then, the PI controller is calculated. After simulation, the proposed approach is implemented on a two-axis piezoelectric actuated micro-positioning system. The experimental results show the advantage of the proposed solution particularly for high frequency reference in comparison to a feedback control structure. Also, the selection of an appropriate model with few parameters results in lower computational load which is a major concern in digital implementation.