Abstract: Aiming at the non-linearity and hysteresis of a piezoelectric actuator, a novel and fast voltage/displacement linear method based on iterative learning control is presented firstly. Then linear data are used in the open-loop precision positioning control. The second method uses the modified preisach model to model the hystersis, and also using the preisach model to perform the research on the open-loop precision positioning control is introduced. Experimental results show that both methods can reach accuracy of sub-micron and the first is better than the second in positioning accuracy. When the control series switch, for the first the input must return to zero voltage or saturation control voltage and carry out next positioning control, while the second can realize the continuous control of arbitrary series.

Key words: Hysteresis, Non-linearity, Open-loop positioning control, Piezoelectric actuator, Preisach model