Dynamic Finite Element Modeling of Electrostatically Actuated Micro Structures Considering Squeeze Film Damping Effect

Abstract

Developing a transient fully-meshed model of coupled-domain microsystems is of paramount importance not only for accurate simulation and design but also for creating more accurate low-order or macro dynamic models. So in this paper, a complete nonlinear finite element model for coupled-domain MEMS devices considering electrostatic and squeeze film effects is presented. For this purpose, we use the Galerkin weighted-residual technique for developing the finite element model that capture the original microsystem's nonlinear behaviors, such as the structural dynamics, the squeeze-film damping, the electrostatic actuation and the geometric nonlinearity caused by inherent residual stresses. In addition, using the Newmark's nonlinear solution, technique, the extracted dynamic equilibrium equations are discretised and simulated. The system dynamic behavior is successfully modeled by using the developed nonlinear finite element model and finally some simulated results of electrostatic microactuator behaviors are verified with experimental findings and are in very good agreement.