Size-dependent nonlinear dynamics of a microbeam based on the modified couple stress theory

In this paper, the nonlinear dynamics of an electostatically actuated microbeam with von karman geometric nonlinearity and squeeze-film damping are studied. The governing equations and the boundary conditions are developed using the modified couple stress theory and Hamilton’s principle. The size-dependent responses are investigated for the primary, super-harmonic, sub-harmonic resonances, and static pull-in voltage. The effects of the...