Characteristics analysis of a plate type linear piezoelectric actuator based on a point contact model

A point contact model is developed to analyze the fundamental characteristics of a single-mode actuation type linear piezoelectric actuator in this paper. The prototype is a plate type piezoelectric actuator using two-phase excitation, which realizes bi-directional motion by changing the vibration mode within different exciting frequencies. Differs from other models, the vibration of barycenter of the stator is taken into account, and the trajectories of driving tip are simulated and measured with and without consideration of the mechanical contact. The results show that a spiral reciprocating motion is generated at driving tip while taking into account the contact and vibration of barycenter of stator. Furthermore, the contact state between the driving tip and linear guide is analyzed by discussing the influence of some important factors including preload and exciting voltage. In addition, the behavior of the force transmission between the driving tip and linear guide is investigated via the classic coulomb friction model to understand the drive mechanism of the single-mode actuation type actuator. Finally, the relations between the output speed and various inputs to the actuator are studied by numerical simulations, which are validated by experiments. It is shown that experimental results are in good agreement with simulation results, which verifies the effectiveness of the proposed model.