Topology optimization of distributed flexure hinges with desired performance

Traditional notch flexure hinges have been widely used in precision engineering, but the lumped notch configuration limits the range of motion. This article presents a synthesis method for designing flexure hinges with distributed configurations using topology optimization. In order to obtain a distributed configuration, an optimization model for the topology optimization of a distributed flexure hinge is developed first. The objective is to maximize the bending displacement while minimizing the axial displacement. The constraint for accomplishing the symmetry requirement is presented. Then flexure hinges having the desired performance are designed on the basis of a distributed configuration. In particular, this work offers optimization models for designing flexure hinges with prescribed compliances and with minimal parasitic motion. This method is implemented based on the popular Solid Isotropic Material with Penalization (SIMP) method, and a number of numerical examples are provided to demonstrate the validity of the proposed method. The results of the examples demonstrate that the flexure hinges obtained have distributed configurations and the desired performances (prescribed compliances or minimal parasitic motion).