Design, Manufacture and Control of a Multi-layer Piezoelectric Actuator

Abstract

A piezoelectric-based micro motion actuator is typically used in micro-scale movement technologies, with the actuator developed to deliver very small movements and high resolution for motion within several micrometer ranges. However, a significant challenge from the strong, nonlinear hysteresis arises affects the piezoelectric materials joining input voltage to output movement, which deteriorates the accuracy of the actuator and causes instability in a closed-loop system. To obtain high precision, accuracy and reduced nonlinear effects, piezoelectric actuators must be controlled with hysteresis compensation. Therefore, this research developed a piezoelectric-based microactuator system with a control scheme based on PID (proportional-integral-derivative) combined with the inverse hysteresis model implemented to compensate for the actuator's hysteresis. Furthermore, a Modified Prandtl-Ishlinskii (MPI) model was used to capture the hysteresis phenomenon, where its parameters were obtained through a system identification process. The inverse model of the hysteresis was then used to generate feedforward signals in the control system. The results showed that the control scheme is able to provide an accurate motion due to the decrease in hysteresis compensation signals from 4.87  to 0.97 . The closed loop control system consisting of the PID control and hysteresis compensation further improved the accuracy of the piezoelectric actuator and reduced the error down to 0.41 . 

Keywords

• hysteresis
• micro motion actuators
• modified prandtl-ishlinskii model
• pid control
• piezoelectric