Structural modeling of a MEMS device: Nonlinear modeling and experimental identification

Piezoelectric and geometrical nonlinear effects on a MEMS isolation device are studied in this paper. The objective is to obtain an accurate modeling of the microstructure, which is a laminated piezocomposite clamped-clamped beam, in order to develop high performance active vibration isolation devices. First, a mathematical modeling, with the governing equations of the beam taking into account geometrical nonlinearities as well as piezoelectric nonlinearities is described and implemented into COMSOL software. Then, the geometrical nonlinear effects of our modeling are validated by comparison with a benchmark from literature. For piezoelectric nonlinearities, the piezoelectric coefficient of actuators is experimentally identified and its polynomial dependence on input voltage is shown. Finally, the frequency-response curves obtained with our modeling for different input voltage amplitudes are presented and discussed. The limitations of the usual basic formulation, where the governing equations are linear and the piezoelectric coefficient is constant, are given.