Motion control of piezoceramic actuators with creep, hysteresis and vibration compensation

In this paper, we develop a new integrated control strategy with creep, hysteresis and vibration compensation to achieve the high-performance motion control of piezoceramic actuators. For this purpose, the direct inverse compensation method is firstly applied to mitigate the asymmetric hysteresis nonlinearity without involving inverse model calculation. The hysteresis caused error is reduced by up to 81.35% to clearly verify the effectiveness of the proposed method. Then, a notch filter is designed to damp the vibrational dynamics of the compensated system, i.e., the plant with inverse hysteresis compensation, which increases the gain margin of the system from 5.4dB to 21.7dB. Finally, the feedback controller is developed to handle the creep nonlinearity, and modeling uncertainties of the system with hysteresis and vibration compensation. The developed integrated controller is demonstrated to improve the bandwidth of the piezo-actuated positioning system from 65Hz to 605Hz. With respect to variations of input frequencies, comparative experimental results are further presented to confirm the significantly better performances of the proposed control strategy in terms of speed and accuracy.