Bistable behavior of electrostatically actuated initially curved micro plate

The axisymmetric snap-through of an initially curved circular micro plate, subjected to a distributed electrostatic force is studied. The analysis is based on a reduced order (RO) model resulting from the Galerkin decomposition, with buckling modes of a flat plate used as the base functions. The results of the RO model are compared with the results available in the literature for initially flat plate and with numerical results obtained for both cases of displacement-independent “mechanical” load and displacement-dependent electrostatic load. The study indicates that a model with at least three degrees of freedom (DOF) is required for an accurate prediction of the equilibrium path, under both types of loading. The analysis shows that due to the nonlinearity of the electrostatic load, the snap-through occurs at a lower displacement than under the “mechanical” load. The presented results also indicate that micro plates of realistic dimensions can be actuated by reasonably low voltages, suggesting the feasibility of the usage of such elements for various applications.