Analysis on Piezoelectric Bimorph Actuator for In-Pipe Micro Robot

Piezoelectric bimorph,which consists of metal thin circular plate having PZT on both sides,is used as actuators of in pipe micro locomotive mechanism.Based on thin plate elastic theory of piezoelectric and metal material combined with the Rayleigh Ritz method,equation for the calculation of resonance frequencies and modes shape of bending modal of structure are derived for two different boundary conditions.As an example,a piezoelectric bimorph with elastic simple support and rigid slipping support is considered,the results obtained from formulation are in very good agreement with those by means of Finite Element Method(FEM),the consistency of the theory and numerical results proved the accuracy and validity of theory model.The effect of thickness of metal and PZT on the resonance frequencies is also discussed.All study provides theoretical foundation for optimal design of actuator for in pipe micro locomotive mechanism.