Piezoceramic bimorph structures have been widely used in recent years as they combine the advantages of different materials. Two thin layers of piezoelectric ceramic are bonded together with the central layer of metal and are electrically connected in parallel and series. The structure produces large strokes with relatively low voltage because of its special bimorph concept. It is necessary to investigate the resonant characteristics of the bimorphs theoretically and experimentally to facilitate the industrial applications. In this study, three experimental techniques are employed to access the resonant characteristics of the bimorphs. These experimental methods are the electronic speckle pattern interferometry (ESPI), laser Doppler vibrometer (LDV), and impedance analysis. Finally, numerical computations based on the finite element method are presented and compared with the experimental measurements. Good agreements of resonant frequencies and mode shapes are obtained from the experimental and numerical results
