On the Lateral Instability Analysis of MEMS Comb-Drive Electrostatic Transducers

摘要

This paper investigates the lateral pull-in effect of an in-planeoverlap-varying transducer. The instability is induced by the translational androtational displacements. Based on the principle of virtual work, theequilibrium conditions of force and moment in lateral directions are derived.The analytical solutions of the critical voltage, at which the pull-inphenomenon occurs, are developed when considering only the translationalstiffness or only the rotational stiffness of the mechanical spring. Thecritical voltage in general case is numerically determined by using nonlinearoptimization techniques, taking into account the combined effect of translationand rotation. The effects of possible translational offsets and angulardeviations to the critical voltage are modeled and numerically analyzed. Theinvestigation is then the first time expanded to anti-phase operation mode andBennet's doubler configuration of the two transducers.