Enhancement of the performance of a micropositioning piezoelectric actuator using Hybrid Fuzzy Robust Control

Piezoelectric actuators are characterized by their nanometer displacement resolution, fast response, high stiffness, and no backlash, so they have been used in micro positioning and precise nano positioning applications. Piezoelectric materials are ferroelectric, they are fundamentally non linearities their response to an input voltage, exhibiting a hysteresis effect between the displacement and the input voltage. A control technique should be applied to compensate the hysteresis effect and maintain the stability of the system. It is desirable to take the effect of nonlinear hysteresis into consideration for enhancing the tracking positioning accuracy of the piezoelectric actuators. In this paper, Hybrid Fuzzy Robust control and Robust μ-Synthesis schemes have been developed for a positioning system driven by piezoelectric actuator. Moreover, the Hybrid Fuzzy Robust Controller gives better tracking error than the Robust μ- Synthesis controller. Experimental results give satisfactory results compared to simulation results. The effectiveness of the proposed control schemes has been validated.