FAST OPTIMAL DESIGN OF SHELL-GRADED-INFILL STRUCTURES WITH EXPLICIT BOUNDARY BY A HYBRID MMC-AABH PLUS APPROACH

Abstract In this study, a hybrid MMC-AABH plus approach is developed for the fast optimal design of shell-graded-infill structures. The key idea is to use a proper description about the graded microstructural infill and the coating shell. To this end, a set of moving morphable components is adopted to represent the boundary of the coating shell, while the graded infill is embodied by spatially varying orthotropic porous configurations. Under such a treatment, with a small number of design variables, both the boundary of the coating shell and the graded microstructure infill can be optimized simultaneously. Other attractive features of the present study are summarized as follows. Firstly, the smooth variation across the microstructural infill can be automatically satisfied based on the proposed approach compared with other similar method. Secondly, with the use of the extreme value principle of Laplace equation, the minimum feature size can be explicit controlled during the optimization. Thirdly, compared with other methods in the frontier, the approach proposed in the present study enjoys considerable reduction in the computation cost and can obtain near-optimal design of coating structure. The effectiveness of the proposed approach is further demonstrated with numerical examples.