Design optimization of a novel symmetrical differential lever displacement magnification compliant mechanism

Abstract

Compliant mechanisms with flexure hinges work based on the deformation of a flexure hinge. The high displacement amplification ratio of the compliant mechanism gives it a large working space, an issue that has been challenging to solve for researchers. Therefore, this study proposes grey relational analysis and the TOPSIS method, the EDAS method and the Taguchi method as means of optimising the displacement magnification of a novel symmetrical differential lever displacement magnification compliant mechanism. The model of the mechanism studied here was designed by SolidWorks. The design variables of the model consisted of variable A, variable B, variable C and variable D. The design variables and their levels were used to create 27 different models with Minitab experimental design software. The displacement and stress of the 27 models was then analysed with the finite element method (FEM) in ANSYS. The results of the FEM analysis were used in optimisation with the methods mentioned above. The FEM results indicated that the designed variables significantly affected the displacement and stress of the symmetrical differential lever displacement magnification compliant mechanism. Issues were also confirmed with five optimisation methods. The predicted and optimal values of the displacement were 0.11276 mm and 0.1179 mm, with error of 4.36%. The input displacement was 0.01 mm, while the displacement magnification ratio was 11.79 times.