Analyzing deflection and torsion of MEMS Bridge

In this paper we discuss and compare regarding various methods in analyzing deflection of MEMS Bridge that the deflection occurs due to a point force and distributed force. We solved deflection of a bridge under the electrostatics forces by considering the linear and nonlinear methods and by comparing the results, we calculated that in which range of dimension the linearity has good accuracy. For this purpose first in Macsyma we wrote a code to solve the nonlinear differential equation numerically and draw the results and solved linear O.D.E. using definite methods, comparing the results then rescaling the all dimensions and forces, we could get the acceptable range of linearity. Then we solved the same problem by Ansys in two cases, linear element and nonlinear element, and then compared the results of Ansys with Macsyma. The results showed that nonlinearity increases exponentially by decreasing the dimensions. Finally, we compare the effect of point force and distributed force on linear and nonlinear analysis. The results showed that increasing the force increases the nonlinearity.