Dynamic Characteristics Of Micro Actuator And Damper Under Electrostatic Actuation

Micro-electromechanical systems(MEMS)in the dynamic characteristics of the micro-structure to ensure the stable operation of MEMS is of great significance.For this reason,the parallel plate electrostatically actuated micro-actuator is the object of this study.The parallel plates of the micro-actuators are simplified into the ideal fixed-support micro beam model.The dynamics of the micro-actuator are studied through the investigation of the micro-beam model.Under the action of DC and AC voltages,microbeams were studied.The Euler-Bernoulli beam model and Galerkin numerical discretization method were used.The multi-scale method was used to study the nonlinear dynamics features and pull-in phenomenon of fixed-supported microbeams with consideration of the primary resonance.The results show that the higher the direct and AC voltage,the smaller the damping value,and the stronger nonlinear characteristics of the system;the system’s response to AC charge is more sensitive to the DC charge charge;the height of curved beam arch increases.The system will in turn appear two different behaviors of softening and hardening;the system may jump or pull-in near the bifurcation.The research results provide reference for reasonable selection of physical parameters and control system vibration behavior.Considering the effect of the non-uniformity of the distribution of the charge concentration on the parallel plates,the micro-actuator components acted on by the electrostatic force.This article discusses the influence of the edge effect produced by the polar plate on the nonlinear dynamics of the system due to the uneven charge concentration distribution.Through the study found: whether the system is affected by the edge effect,which is related to the initial distance from the upper plate to the lower plate.When the ratio of the thickness of the plate to the initial distance from the lower plate is less than 1,The edge effect of the plate needs to be considered.Because of the edge effect,the nonlinear characteristics of the research model will be enhanced.In order to eliminate the effects of edge effects,we have found that when the plate thickness is about three times the plate distance or more,the edge effect has no effect on the nonlinear characteristics of the system.In this case,theedge effect of the plate can be ignored.This paper also studies the dynamic characteristics of the miniature shock absorber.The three DOF nonlinear vibration model is simplified from the shock absorber,the control equation is established on the three DOF model,and the numerical method is used to solve the equation.Finally,the relationship between amplitude and frequency is obtained.The working effect of the shock absorber was investigated under the condition that the electrostatic excitation frequency is close to the main frequency of the component,and it was concluded that when the damper frequency is close to the main frequency of the component,the frequency of the damper is closer to the component frequency,The ratio of the amplitude is larger,the larger the amplitude of the damper is,and the smaller the amplitude of the main member is,the better the damping effect is.On the contrary,the damping effect of the damper will be worse.