dynamic and static pull-in instability of electrostatically actuated nano/micro membranes under the effects of casimir force and squeezed film damping

in the current study the effect of casimir force and squeezed film damping on the pull-in instability and dynamic behavior of electrostatically actuated nano and micro electromechanical systems is investigated separately. linear elastic membrane theory is used to model the static and dynamic behavior of system for strip, annular and disk geometries. squeezed film damping effect is modeled using nonlinear reynolds equation. both equation of motion and nonlinear reynolds equation are first nondimensionalized then they are discretized and solved by means of finite element method. first static pull-in instability analysis is performed and validated by previous researches then dynamic pull-in values are investigated and compared with static pull-in parameters. in the next step the effect of squeezed film damping and ambient pressure and also casimir force on the dynamic behavior of system is studied. results shows significant effect of casimir force and squeezed film damping on the system which is considerable for fabrication and design. keywords: mems and nems, pull-in instability, squeezed film damping, casimir force, linear elastic membrane, fem keywords: mems and nems, pull-in instability, squeezed film damping, casimir force, linear elastic membrane, fem