Ultra-High Speed Positioning Control of a Piezoelectirc Actuator by Using Discrete-Time Two-Degree-of-Freedom H_∞ Control

Abstract

The piezoelectric actuator has high-speed response in comparison with the electro-magnetic actuator. However it is not easy to achieve the both of high-speed and high-precision response, because the piezoelectric-element has nonlinear property such as hysteresis effect. So the feedback control must be required to achieve good performance.
In this paper, we develop a new control design method to achieve the both of high-speed and high-precision response for piezoelectric actuator by using the discrete-time H_∞ control method and the two-degree-of-freedom control scheme. The effectiveness of our proposed method has been shown by the simulation and the experimental result. The most important contribution of our study is that our method can be directly used to the commercial machine.