Modeling and control of a novel X-Y parallel piezoelectric-actuator driven nanopositioner

In this paper, a novel X-Y parallel piezoelectric-actuator driven nanopositioner is studied from the perspectives of design optimization, dynamical modeling, as well as controller design for high precision positioning. FEM (Finite Element Method) and dynamical modeling are provided to analyze the mechatronic structure of the proposed two-dimensional nano-stage, where the system model including hysteresis loop is derived analytically and further verified experimentally. A robust control architecture incorporating an H_∞ controller and an anti-windup compensator is then developed to deal with the hysteresis and saturation nonlinearities of the piezoelectric actuators. Real time experiments on the positioning of the nano-stage demonstrate good robustness, tracking performance and recovery speed in the presence of saturation.