Disturbance Observer-Based Hysteresis Compensation for Piezoelectric Actuators

We present a novel hysteresis compensation method for piezoelectric actuators. Instead of using any particular mathematical model of hysteresis, we consider the hysteresis nonlinearity as a disturbance over a linear system. A disturbance observer (DOB) is then utilized to estimate and compensate for the hysteresis nonlinearity. In contrast to the existing inverse model-based approaches, the DOB-based hysteresis compensation does not rely on any particular hysteresis model, and therefore provides a simple and effective compensation mechanism. Experimental validation of the proposed hysteresis compensation is performed on a PMN-PT cantilever piezoelectric actuator.