Topology Optimization of Flexure Hinges with Distributed Stress for Flexure-Based Mechanisms

Flexure hinges have been widely used in precision positioning, precision measurement and other fields due to its high-precision features. Traditional notch flexure hinges often exhibit local stress, which limits the range of motion and reduces the fatigue life of flexure-based mechanisms. This paper proposes a conceptual method for designing flexure hinges with distributed stress by using the topology optimization approach. The topology optimization model is developed. The objective function is presented by equally minimizing the ratio of axial displacement and bending displacement and the maximum stress. A global P-norm stress measure is used to reduce the stress level of flexure hinges. The solid isotropic material with penalization (SIMP) is adopted to describing the topology optimization problem. Numerical examples are used to demonstrate the validity of the proposed method.