Theoretical dynamic model of the piezoelectric actuator with multi-DOF loading structure in process of microforging

Abstract

A piezoelectric actuator is applied in a microforging system which was designed specially by maximizing its structural rigidity to study size effects in microforming. To generate accurate movement in micrometer/nanometer scale, a dynamical model of the piezoelectric actuator is in need. A new approach which considers the effect of multi-degree-of-freedom (multi-DOF) loading structures on the dynamics of the actuators is proposed in this paper. Merging the constitutive equations of the piezoelectric materials to the dynamics of single-DOF and two-DOF external structures, theoretical models of the actuator are presented. By utilizing dynamic stiffness, the dynamical models are applicable to the piezoelectric actuators with multi-DOF loading structures. A general dynamic model of the piezoelectric actuator with multi-DOF loading structure will predict the behavior of the actuator. The linear model of the piezoelectric actuator with multi-DOF external structure is the main contribution of this paper.