A unified framework for explicit layout/topology optimization of thin-walled structures based on Moving Morphable Components (MMC) method and adaptive ground structure approach

Abstract

In this paper, we introduce a unified framework for explicit layout/topology optimization applicable for designing various types of thin-walled structures such as plate, shell, sandwich plate, grid structure etc. The novel aspect of this framework is that the thin-walled structure under design is assumed to be composed of a set of moving morphable structural components whose locations/geometries are described by explicit parameters, and the entire structure is modeled by dynamically updated shell elements with adaptive remeshing technique, which can effectively reduce the computational cost and improve the analysis accuracy. Furthermore, an adaptive ground structure approach driven by movable nodes is also developed to regularize the optimization process. Compared with existing methods, the proposed method can not only achieve clear material distribution and component placement, but also has the capability of easily controlling the feature sizes of the components, which is very important for preventing the components from local failure/buckling. In addition, benefiting from the explicit geometry description of the structural components, the optimized designs can be seamlessly imported into CAD systems for subsequent treatment without resorting to any post-processing process. This is very helpful for practical engineering applications. Some representative numerical examples are presented to demonstrate the validity and efficiency of the proposed framework.