Fillet Design in Topology Optimization

Topology optimization is a design tool to identify the best material layout in a prescribed design domain. Sharp connections between elements in the topology optimization results will cause stress concentration. To solve this problem, this paper proposes a fillet design method for density-based topology optimization. With the method, the Heaviside-based morphological filters are firstly constructed, which include the advanced open-close filter and close-open filter. Then, a dual projection method is proposed to achieve the round corner designs. Finally, the proposed method is tested through the compliance mechanism problem. Experimental results show that the proposed method can effectively avoid the appearance of sharp corners in the final designs. Moreover, the dual projection filters are prone to produce design without single hinge connections, which is beneficial for improving the manufacturability of the topology optimization results.