Topology optimization of Shell–Infill structures with enhanced edge-detection and coating thickness control

Abstract

Topology optimization is a valuable tool in additive manufacturing, but its application requires careful consideration of various constraints to refine the optimization outcome. In additive manufacturing, components often consist of two distinct regions: a solid shell forming the exterior and a porous infill occupying the interior. This work introduces a novel approach based on the SIMP (Solid Isotropic Material with Penalization) method, aiming to optimize both the shell and infill concurrently. The proposed method incorporates a series of filtering processes that effectively separate the structure into two phases: the shell and the infill. This separation allows for precise control over the desired coating thickness by employing the SUSAN edge-detector method and introducing a new parameter designed for explicit thickness control. Additionally, a new constraint based on the structural skeleton has been introduced to ensure the preservation of a minimum length scale.