Parametric identification of piezoelectric microscale resonators

Piezoelectrically actuated and sensed microscale resonators have been widely studied for filtering, communication and sensing applications. In this effort, to characterize these resonators, the nonlinear frequency-response behavior of these resonators is examined and parametric identification is carried out. A nonlinear beam model is used with a single-mode approximation to produce a forced Duffing oscillator. Nonlinear analysis is used to obtain the frequency-response equation, and this equation is used along with a least-squares minimization scheme to identify the linear and nonlinear parameter values in oscillator models describing the microscale structures. A linearized analytical model of the stepwise axially varying resonator is also used to obtain additional system parameters. The experimentally identified parameter values are found to be in agreement with predicted values obtained from a nonlinear beam model. Parameter values obtained from multiple sets of data for PZT and AlGaAs microresonators are used to observe trends with respect to a variety of operating conditions.