A simple robust controller for hysteresis and resonance compensation of piezoelectric actuators

Hysteresis and resonance dynamics are typical adverse effects associated with the piezoelectric (PZT) actuators. To eliminate the loss of positioning accuracy due to these effects, we propose a simple two degree-of-freedom (2DOF) control scheme for the PZT actuators, which consists of a feedforward and a feedback compensator for hysteresis and resonance compensation and for robust step reference tracking. Despite the proposed controller is on par with the existing 2DOF control methods, its specific structure offers significant design simplicity. The experimental results on an actual PZT nanopositioner show that the designed controller can be easily implemented and achieve superior performance for hysteresis and resonance compensation.