Topological design of hinge-free compliant mechanisms using the node design variables method

Abstract

The designs of compliant mechanisms using topology optimization typically lead to de facto hinges in the created mechanisms which can cause high stress concentration and are difficult to manufacturing. Topology optimization of hinge-free compliant mechanisms using the node design variables method is proposed. Within defined sub-domain, the projection function independent on element mesh is adopted to represent the relationship of node design variables and node density variables, which can achieve the minimum length scale constraint of the topological solution to avoid generating the de facto hinges. The method of moving asymptotes is adopted to solve the topology optimization problem. The numerical examples are presented to show the feasibility of the approach. It can obtain hinge-free compliant mechanisms which is convenient for manufacturing.