Smooth topological design of structures with minimum length scale and chamfer/round controls

Abstract Topology optimization is a powerful tool for designing high-performance structures. However, the structures resulting from topology optimization usually have complex geometries , which makes them difficult or costly to fabricate. As a result, topology optimization is often used for the conceptual design of product structures. In this paper, a topology optimization method considering manufacturing constraints is proposed under the fixed finite element mesh . The minimum length scale and chamfer/round are controlled as required based on the floating projection topology optimization (FPTO) method, where the linear material interpolation scheme is adopted instead and the material 0/1 distribution is realized by applying sequential constraints on the elemental design variables through the floating projection. The minimum length scale is strictly controlled with the help of the structural skeleton , which is extracted from the structural topology by using a graphic thinning algorithm. Meanwhile, boundary filtering is proposed by using a variable filtering radius to control chamfers and rounds. Two-dimensional and three-dimensional numerical examples demonstrate that the proposed topology optimization algorithm is effective for designing the stiffest structures with smooth boundaries, desired minimum length scale and chamfers/rounds, so as to improve their manufacturability.

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