Controlling bistability in microelectromechanical resonators

Chaos. 2008 Mar;18(1):013103. doi: 10.1063/1.2825598.

Abstract

For a microelectromechanical (MEM) resonator, the combination of mechanical nonlinearity and electrical driving force can lead to bistability. In such a case, the system exhibits two coexisting stable oscillatory states (attractors): one with low and another with high energy. Under the influence of noise, with high probability the system can be perturbed into the low-energy state. We propose a robust control scheme to place the system in the high-energy state. Our idea is not to pull the system out of the bistable regime but instead to take advantage of the nonlinear dynamics to achieve high-energy output. In particular, our control scheme consists of two steps: bifurcation control that temporarily drives the system to a regime with only one attractor, one that is the continuation of the high-energy attractor in the bistable regime; and ramping parameter control that restores the bistability while maintaining the system in the high-energy attractor. We derive an analytic theory to guide the control, provide numerical examples, and suggest a practical method to realize the control experimentally. Our result may find potential usage in devices based on MEM resonators where high output energy is desired.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.