High-bandwidth open-loop motion control of a piezo-positioning mechanism based on a composite electromechanical dynamic model

Abstract

The piezo-positioning system with high dynamic performance is urgently needed in the field of precision manufacturing and precision instrumentation. The observed rate-dependent hysteresis presents more challenges and difficulties for accurately modeling the response behavior of the piezoelectric stack actuators over the last several decades. Our previous research shows that the rate-dependent characteristics may be caused by the dynamic characteristics of the power amplifier. In order to achieve the high-bandwidth and high-speed motion control accuracy, we propose an open-loop compensation control method of a piezo-positioning mechanism based on a composite electromechanical dynamic model. The dynamic model can describe the dynamic characteristics of the power amplifier, the inverse piezoelectric effect and the dynamics of the mechanism. Experimental results show that the proposed control method can achieve precise motion control of the piezo-positioning mechanism within 1–800 Hz bandwidth.