Hysteresis compensation for piezoelectric actuator based on adaptive inverse control

Hysteresis hinders the wider applicability of smart materials in actuators. An adaptive inverse control approach based on the so-called Prandtle-Ishlinskii hysteresis operator 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. The method was applied to a micropositioning system driven by the PZT. In comparison to the conventionally open-loop control, the non-linearity error of applying adaptive inverse control is lowered from about 17.3 to about 2%.