Cloaking structure designs have been widely performed in a form of metamaterial development. However, physics-based design approach makes it difficult to define complex material profiles. This study proposes an alternative design method for multi-directional cloak design via topology optimization method using a dielectric material. The phase field design method, which uses the reaction-diffusion equations combined with the double well potentials as the update scheme for design variables, is employed for systematic derivation of a topological configuration of the cloaking structure. In addition, the concept of symmetric design sensitivity mapping is introduced for multi-directional cloaking effect. Design results of four-, six- and eight-directional cloak are presented, and experimental verification was performed for six-directional cloak using the fabricated structure through 3D printing technology.

隐身结构设计已以超材料开发的形式广泛进行。但是，基于物理的设计方法很难定义复杂的材料轮廓。本研究提出了一种通过使用介电材料的拓扑优化方法进行多方向披风设计的替代设计方法。相场设计方法将反应扩散方程与双势阱势结合作为设计变量的更新方案，用于系统化隐身结构的拓扑结构。另外，引入了对称设计灵敏度映射的概念以实现多方向隐身效果。给出了四向，六向和八向披风的设计结果，