A novel rate-dependent hysteresis modeling and position control technique for piezo-actuated bimorph beams

Piezoelectric cantilever actuators are widely used in micro/nano-positioning applications due to their relatively accurate response and large operating bandwidth. One of the main obstacles in the way of implementing high-accuracy position tracking in high frequencies is the piezoelectric hysteresis phenomenon. It is known from previous research that piezoelectric materials exhibit a rate-dependent hysteresis loop. The purpose of this article is to obtain a novel hysteresis model that can accurately describe the output of the piezoelectric actuator. This is done by introducing a hysteresis model in the form of an actuated linear dynamic system. This model provides the ability to capture both rate-dependence and magnitude characteristics of the system, and it is simple and easy to implement in real-time. As a result, the proposed method accurately predicts the position of the piezo-actuated beam in a wide range of input frequencies and amplitudes. To demonstrate its effectiveness, the proposed hysteresis model is used along with a robust control loop to track the position of a piezo-actuated beam plant. It is shown using experimental results that utilizing this model leads to accurate position control in a wide range of frequencies.