Force optimization of a linear motion type electrostatic microactuator using finite element method (FEM) analysis for high thrust performances

Abstract

Two linear electrostatic microactuators were designed in order to optimize the force characteristics of a linear motion type electrostatic microactuator for high thrust performance. Finite element method (FEM) analyses are used to analyze and optimize the microactuator's designed parameters. The two structures are designed to be linear-actuated and are compared under similar conditions. The objective of this research is to design, compare and analyze the effect of varying the microactuator's parameters to the actuation force (Fx). First, the two structures are designed using ANSYS Maxwell 3D; i.e (a) Non-Skew-Type Electrostatic Microactuator and (b) Skew-Type Electrostatic Microactuator. Next, the thrust forces were evaluated using Finite Element Method (FEM) analyses in order to optimize the microactuator's parameters. The FEM analyses are carried out by (i) varying the ratio number of electrode-to-spacer (ii) varying the microactuator's gap and (iii) varying the microactuator's size. The FEM analysis shows that the Skew-Type Electrostatic Microactuator exhibit greater actuation force, 2.7857μN compared to the Non-Skew-Type Electrostatic Microactuator, 1.7476μN; when the ratio number of electrode-to-spacer is 1.0:2.5.