Modal analysis of piezoelectrically actuated plates with built-in stress by computationally augmented interferometric experiments

The conventional laser doppler vibrometers for modal analysis of micro-structures are expensive and sometimes inaccessible. In this work, a compact, fiber-based interferometric setup is used to carry out the modal analysis of initially deflected piezo-actuated micro-plates with different designs. The finite element method provides actual mode shapes visualization in the frequency range up to 100 kHz using the spectral results of vibration measurements performed at a few selected spots of the plate. This method is capable of finding the resonance frequencies and distinguishing the mode shapes. It has also allowed us to investigate the impact of bias voltage on the actual values of the resonance frequencies.