Development and validation of an automated FEM-based design optimization tool for continuum compliant structures

Abstract

This paper presents a design optimization method for continuum compliant structures. The developed optimization tool enables automated design, analysis and optimization of the compliant structures in a single simulation environment. The associated algorithm used automatically analyses the stress distribution occurring under certain loading and deformation conditions of initial designs defined by the user, adjusts a uniform stress distribution among individual flexure hinges by automated dimensioning and finalizes the design by integrating mechanical stops automatically matched with the kinematic capacity of individual hinges. In order to prove the advantages of the proposed optimization method, validation tests were performed under static and dynamic loading conditions. Results of the experiments showed that, compared to the non-optimized ones, optimized structures with the developed tool exhibit more uniform curvatures which indicate more even stress distribution among the individual hinges; up to 25% value increase in terms of maximum bearable load and maximum permissible deflection angle; less plastic deformation in case of overloading and up to 100% increased fatigue life.