Analysis of Hysteresis-Free Creep of the Stack Piezoelectric Actuator

A modified log-type creep model without hysteresis of the stack piezoelectric actuator is presented. For high-speed micro-/nanopositioning system, the time scale should be less than one second for creep modeling and control in the stack piezoelectric actuator. But creep effect was studied in the frame of minutes in previous works. Meanwhile, parameters of the classical creep models are hard to be determined. By the proposed model, the hysteresis and the creep effect can be separated. A series of experiments have been performed, where different staircase voltages have been applied to the actuator. There are two clear rules to follow in small duration and different heights to determine parameters. Firstly, starts from fixed point either in ascending stage or in descending stage and rotates clockwise. Secondly, converges to a small vicinity of a constant when the duration is small enough.