Kinetostatic and Dynamic Analyses of Micro-Positioning Compliant Mechanism Equipped with Piezoelectric Actuator

This paper proposes a compliant amplifying mechanism for micro-positioning applications by piezoelectric actuators. This mechanism has the advantage of being supported by both input and output ports, enhancing its out-of-plane stiffness, and making it more applicable for positioning devices. However, this property makes the mechanism more complicated for kinetostatic analyses. In this paper, analytical methods are presented to model the kinetostatic and dynamic behaviors. In addition, to take the nonlinear behavior into account, the hysteresis behavior of the mechanism and piezoelectric has been identified by the Prandtl-Ishlinski model. The results are validated by the finite element method (FEM) and experiments. The analytical method can estimate the amplification ratio, output stiffness and input stiffness of the mechanism with a deviation of approximately 9.5%, 20%, and 2%, respectively. Additionally, the resonant frequency obtained from the dynamic stiffness model is 394 Hz, which closely aligns with the results obtained from FEM simulation and experiments, i.e., 371 Hz and 365 Hz, respectively. Based on the conducted analyses, it can be concluded that the dynamic stiffness modeling results indicate a satisfactory correlation between the analytical and FEM method in terms of the amplification ratio and resonance frequency. Furthermore, the hysteresis identification model is appropriately linked with the experimental hysteresis loop with an RSME of less than 2 for input signals with 1,2, and 4 second periods.