Dynamic Analysis of Micro-Electro-Mechanical Systems

The subject of this paper is dynamic analysis of Micro-Electro-Mechanical Systems (MEMS). MEMS are integrated, movable microstructures with electronics, in the 0⋅1–1000 μm size range. Dynamic analysis of MEMS is complicated by the fact that there are two physical domains, electrical and mechanical, with non-linear coupling between them. Numerical simulation of the dynamics of MEMS is carried out by a hybrid BEM/FEM (Boundary Element and Finite Element Method) approach, FEM for the structure and BEM for electrostatic analysis. Several numerical techniques are proposed for time-integration in order to obtain the non-linear dynamic response. These techniques are tested on a ‘generic’ MEMS device, a microtweezer. The Modified Newmark Method is determined to be the best approach for simulation. Various interesting non-linear phenomena are observed from the numerical simulations. Some of these non-linearities have also been observed in previous experiments with MEMS. A simple physical analogue to the microtweezer is proposed. Study of this model helps one understand some of the complex non-linear responses of the microtweezer.