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...

Damping in air gaps is studied at RF frequencies and modelled with a viscoelastic wave propagation model, since the traditional squeezed-film damping model is not valid in the MHz regime. The FEM study shows that above a certain frequency the wave propagation in the air gap can be modelled assuming closed damper borders. This closed-border problem is solved analytically from the linearized Navi...

The accelerating fields (e. g. centrifugal acceleration and constant acceleration) can change the physical performance of nano-sensors significantly. Herein, a new size-dependent model is developed to investigate the scale-dependent dynamic behavior of nanowire-fabricated sensor operated in an accelerating field. The scale-dependent equation of motion is developed by employing a consolidation o...

⎯ A technique for dynamic positioning of the movable electrode in an electrostatic actuator enables stable operation beyond the pull-in displacement and is used to perform squeeze-film damping measurements for different film thicknesses. Measurements at Knudsen numbers ranging between 0.03 and 0.18 are performed. Compact parallel-plate squeeze-film models are verified using the experimental res...

In this article the modeling and control design aspects of an electrostatic microactuator (EmA) with squeezed thin film damping effects are presented. The modeling analysis of the squeezed film damping effect is investigated in the case of an EmA composed by a set of two plates. The bottom plate is clamped to the ground, while the moving plate is driven by an electrically induced force which is...

Damping is a critical design parameter for miniaturized mechanical resonators used in microelectromechanical systems (MEMS), nanoelectromechanical systems (NEMS), optomechanical systems, and atomic force microscopy for a large and diverse set of applications ranging from sensing, timing, and signal processing to precision measurements for fundamental studies of materials science and quantum mec...

In this article the modeling aspects of an electrostatic microactuator (μ-A) with squeezed thin film damping effects are presented. The μ-A is composed of a microcapacitor whose one plate is clamped on the ground while the other plate is floating on the air. Its highly nonlinear dynamic model is linearized at various operating points. A robust PID-controller is designed with its parameters-tuni...

we present a reduced-order model of the squeezed-film damping phenomenon which is valid for flexible structures, large displacements (with respect to the gap) and small pressure variations (with respect to the ambient pressure). This reduced-order model is obtained by transforming the Reynolds equation into a form more amenable to modal projection techniques. Our approach is validated by compar...

The squeezed-film damping component of the pull-in time of an electrostatically-actuated micromechanical fixed-fixed beam is shown to be a sensitive, and nearly linear function of ambient air pressure in the measured range of 0.1 mbar to 1013 mbar (1 atm or 760 Torr). Pull-in time simulations, based on a one-dimensional macromodel using a damping constant proportional to pressure, are in good a...