Modeling and Analysis of Multi-DOF Piezoelectric Actuator with Two Directional Polarization

Numerical investigation of bulk piezoelectric actuator with two directional polarization vectors is presented in the paper and possibilities to use it for multi-DOF positioning are analyzed. Investigated piezoelectric actuator has beam shape with square type cross-section. Advance feature of the actuator is that actuator has two perpendicular directions of polarization of the first and second half along his length. Both polarization vectors are perpendicular to the longitudinal beam axis and are perpendicular to each other. Two directional polarizations are used to achieve flexural oscillations of the actuator in perpendicular planes. Electrodes of the actuator are divided into three sections and different excitation schemes are used to achieve longitudinal and flexural oscillations. Applying superposition of these oscillation modes allows obtaining multi-DOF motion of positioning object. Numerical investigation of the piezoelectric actuator was performed employing finite elements method. Natural frequencies, modal shapes and the actuator response to various excitation regimes were investigated. Trajectories of contact point have been calculated and results of the numerical analysis have been discussed.