Multiple-frequency Tracking Control of Piezoelectrically-driven Micro/Nano-positioning Systems

In this article, a novel modeling and control methodology is proposed for feedforward compensation of hysteresis nonlinearity and dynamical vibrations of piezoelectric actuator in various range of frequency operation. By integrating a modified Prandtl-Ishlinskii hysteresis operator with a second order linear dynamics, a nonlinear dynamic model is developed and experimentally validated for a piezoelectrically- driven nano-positioning system. Based on the inverse hysteresis model and the actuator dynamics, a feedforward controller is then proposed and its stability is discussed. Eventually, the performance of the controller is verified for the nano-positioning system. Experimental results demonstrate that the controller is capable of precisely tracking multiple- frequency reference trajectories in various rates.