As a class of smart material-based actuators,piezoelectric actuators have been widely applied in the micro-nano actuating equipment. However,the nonlinearities existing in the smart materials become the main
obstacle for the improvement of actuating precision. Considering the electromechanical characteristics of the piezoelectric actuator,a modeling method is proposed to characterize the input-output relationship of the
piezoelectric actuating system with an external mechanical load in a wide working frequency range. The proposed
model is based on the rate-dependent PrandtlIshlinskii (RDPI) hysteresis model and shows an effective way to work around the limitation of RDPI hysteresis model,representing the effects analytically caused by the mechanical load with an increase in actuating frequency. With the mechanical load 2. 94N,the experiments for the piezoelectric actuating system are conducted in the frequency range 1 ~80 Hz. Good agreement is found between the mea
sured and predicted input-output curves to show the effectiveness of the proposed modeling method.