Sang Won Jung, Hyo Geon Lee, Jae Woo Jung, Jae Hyun Kim, Seonbin Lim, Youngjin Park, Onemook Kim, Jaehyun Lim, Kijun Seong, Daehee Lee, Minjae Ko, No-Cheol Park, Jun Young Yoon
J. Korean Soc. Precis. Eng. 2024;41(11):913-920. Published online November 1, 2024
Nonlinear hysteresis effects in piezoelectric fast steering mirrors (FSMs) are major culprits of deteriorating the servo performance and reducing the robustness of a control system. In order to compensate for such nonlinearities, this paper presents an identification and compensation method of piezoelectric hysteresis using frequency response measurements. The relationship between hysteresis curves and frequency response was analyzed using various amplitudes of input voltage and measured output displacements. Results proved that hysteresis curves could be reconstructed based on frequency response measurements. By utilizing an inverse function from reconstructed hysteresis curves, parameters for the compensation model were identified. Experimental results showed that the maximum range of output displacement at the nominal position due to hysteresis was significantly decreased by 76% when the hysteresis model identified by the proposed frequency-domain method was used. In addition, the compensated frequency response showed consistent results regardless of input amplitudes, implying that linear dynamics of the piezoelectric FSM could be separately measured.