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

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.