Adaptive inverse control for piezoelectric actuator with dominant hysteresis

Piezoelectric actuator controlled by voltage shows serious hysteresis phenomena, which severely degrades the positioning accuracy. Based on Prandtle-Ishlinskii hysteresis operator, an adaptive inverse control approach is presented for reducing hysteresis. The weights of the model are identified by using LMS algorithm. The realization of an inverse feedforward controller for the linearization of a piezoelectric actuator is formulated. Experiments were performed on a micro-positioning system driven by piezoelectric actuators. The results show that the presented adaptive inverse control lowers the non-linearity error from about 17.3 to about 2% in comparison to the conventionally open-loop control.