Hysteresis compensation of piezo actuators

In recent years several approaches have been proposed to compensate for the hysteresis behavior of piezo actuators. However, they are very restrictive, either on the hardware side or in the choice of possible reference trajectories. In this paper, alternative hysteresis compensators for arbitrary trajectories are presented which use standard equipment. Two approaches of different complexity are proposed. First a sensorless control design is introduced where a Maxwell model is used to compensate for the hysteresis and a notch filter for the first resonance peak. For higher precision requirements, a linear feedback controller taking into account the gain variation of the hysteresis is suggested. The two designs are illustrated on an experimental setup and compared with respect to implementation cost and dynamical properties.