Topology optimization of self-supporting structures with polygon features for additive manufacturing

This work aims at developing a topology optimization method for the design of self-supporting structures that can be directly realized by additive manufacturing (AM). In the proposed method, polygon-featured holes are introduced as basic design primitives whose movements, deformations and intersections allow to control the structural topology. In addition, overhang constraints are introduced directly into the geometry description, so that the inclined angles along the overhang boundaries are not less than the critical overhang angle (COA). Meanwhile, unprintable V-shaped areas caused by polygon intersections are gradually eliminated through polygon modifications and re-optimization. Numerical examples are tested to demonstrate the effectiveness of the proposed method.