Simulation of shaped comb drive as a stepped actuator for microtweezers application

Department of Electrical and Computer Engineering, University of Manitoba, Winnipeg, Man., Canada R3T 5V6
Sensors and Actuators A: Physical 01/2005; DOI: 10.1016/j.sna.2005.03.031

ABSTRACT Finite element analysis is used to simulate electrostatic actuated, shaped comb drives operating under dc conditions (zero actuating frequency). A dynamic multiphysics model is developed using the arbitrary Lagrangian–Eulerian (ALE) formulation. Results show the coupled interaction between the electrostatic and mechanical domains of the transducer. The analysis is based on the evolution of electrostatic force versus comb finger engagement. The relationship between incremental lateral displacement and actuation voltage illustrates the potential for stepped movement for a shaped comb drive. Additionally, through numerical simulations, this project determines an optimum design for a dc-actuated comb drive, which has controllable force output and stable engaging movement.

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