Structural response investigation of a triangular-based piezoelectric drive mechanism to hysteresis effect of the piezoelectric actuator

摘要

A new piezoelectric-based mechanism was proposed, modeled and tested. This mechanism was basically designed to be periodically excited while in contact with a driven surface. Two piezoelectric elements located by the angle of 90 relative to each other are used to create elliptical motion on tip of the mechanism depending on the applied phase difference. In order to ensure the designated elliptical motion is achieved, a dynamic analysis of the system is carried out utilizing the constitutive equations relating to the dynamic response of piezoelectric element with the voltage input under external loading. However, it is widely known that piezoelectric materials are subjected to hysteresis nonlinearity, which causes the constitutive equations cannot be implemented directly. On the other hand, the constitutive equations have been, originally derived based on linear assumption that neglects the nonlinearity of hysteresis in piezoelectric materials. In this paper, the hysteretic effect of the piezoelectric actuator is taken into consideration to characterize and model the dynamic response of the designated structure. The trajectory output of the structure is simulated using finite element approach while the excitation input to the model, -incorporating the hysteresis properties-, is predicted based on the proposed formulation. The simulation results exhibit good agreement to the tip trajectory of the mechanism at relatively low frequency ranging from 50 Hz to 200 Hz.