Modelling and analysis of omni-directional piezoelectric actuator

A study of a novel multi-degree-of-freedom piezoelectric actuator is given in the paper. Design of the actuator is based on the implementation of bending vibrations of a circular plate. The actuator consists of a vibrating disc with the driving tip mounted at the disc centre and a piezoceramic disc. This actuator can move a slider in two perpendicular directions in the plane and achieve a curvilinear or rotational motion of the positioned object depending on the excitation scheme of the electrodes. Numerical modelling based on the finite element method was performed to find resonant frequencies and modal shapes of the actuator and to calculate the trajectories of contact point's movements under different excitation schemes. The transient dynamic analysis of the actuator was performed to simulate the motion of the slider. A contact between the driving tip, slider and slider-way was taken into account in the finite element model. A prototype actuator was made and measurement results of actuator's top surface's oscillations are given. Results of the numerical and experimental investigation are analysed and discussed.