Superharmonic Resonance of an Electrically Actuated Resonant Microsensor
Eihab M. Abdel-Rahman and Ali H. Nayfeh
Virginia Polytechnic Institute and State University, US
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.
NSTI Nanotech 2003 Conference Technical Program Abstract