Authors: E.M. Abdel-Rahman and A.H. Nayfeh
Affilation: Virginia Polytechnic Institute and State University, United States
Pages: 440 - 443
Keywords: MEMS, resonant sensors, forced vibrations, superharmonic resonance
We investigate the response of a microbeam-based resonant sensor to a superharmonic electric actuation. The model incorporates the nonlinearities associated with moderately large displacements and electric forces. The method of multiple scales is used to obtain two first-order nonlinear ordinary-differential equations that describe the modulation of the amplitude and phase of the response and its stability. We present typical resonator frequency-response and force-response curves. The curves demonstrate the existence of multivalued solutions. These curves consist of three branches which meet at two saddle-node bifurcation points. The results provide an analytical tool to predict the microsensor response to a superharmonic excitation, specifically the locations of sudden jumps and regions of hysteretic behavior, thereby enabling designers to safely use this signal as a measuring signal.