Improved Hysteresis Model of Micro-Positional Stage Based on PI Model

In order to obtain higher accuracy and faster calculation speed of hysteresis model of the piezoelectric micro-positional stage, the traditional PI hysteresis model is improved in this paper. First, based on the fact of that the slopes of the first half of the initial loading curve for the piezoelectric micro-positional stage change much while the slopes of the second half change little, the PI hysteresis model of the stage is established by the non-equiinterval threshold value. Then, the established model is identified by optimizing the minimum L22-norm of the model errors. The results show that the maximum error and average error of the model are 0.71 μm and 0.23 μm in the displacement range of 22.75 μm, respectively.