This article presents a topology optimization method for structures consisting of multiple lattice components under a certain size, which can be manufactured with an additive manufacturing machine with a size limit and assembled via conventional joining processes, such as welding, gluing, riveting, and bolting. The proposed method can simultaneously optimize overall structural topology, partitioning to multiple components and functionally graded lattices within each component. The functionally graded lattice infill with guaranteed connectivity is realized by applying the Helmholtz PDE filter with a variable radius on the density field in the solid isotropic material with penalization (SIMP) method. The partitioning of an overall structure into multiple components is realized by applying the discrete material optimization (DMO) method, in which each material is interpreted as each component, and the size limit for each component imposed by a chosen additive manufacturing machine. A gradient-free coating filter realizes bulk solid boundaries for each component, which provide continuous mating surfaces between adjacent components to enable the subsequent joining. The structural interfaces between the bulk solid boundaries are extracted and assigned a distinct material property, which model the joints between the adjacent components. Several numeral examples are solved for demonstration.

中文翻译：

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具有块状固体界面的功能梯度晶格结构的多组分拓扑优化

本文提出了一种由一定尺寸下的多个晶格组件组成的结构的拓扑优化方法，该结构可以用具有尺寸限制的增材制造机器制造，并通过焊接、胶粘、铆接和螺栓连接等常规连接工艺组装。所提出的方法可以同时优化整体结构拓扑，划分为多​​个组件和每个组件内的功能分级晶格。通过在具有惩罚 (SIMP) 方法的固体各向同性材料中的密度场上应用具有可变半径的亥姆霍兹偏微分方程 (Helmholtz PDE) 滤波器，可以实现具有保证连通性的功能梯度晶格填充。通过应用离散材料优化（DMO）方法实现将整体结构划分为多个组件，其中每种材料都被解释为每个组件，以及所选增材制造机器对每个组件施加的尺寸限制。无梯度涂层过滤器实现了每个组件的整体固体边界，从而在相邻组件之间提供连续的配合表面，以实现后续连接。提取大块固体边界之间的结构界面，并为其分配不同的材料属性，从而对相邻组件之间的接头进行建模。解出几个数例进行演示。在相邻部件之间提供连续的配合面，以实现后续连接。提取大块固体边界之间的结构界面，并为其分配不同的材料属性，从而对相邻组件之间的接头进行建模。解出几个数例进行演示。在相邻部件之间提供连续的配合面，以实现后续连接。提取大块固体边界之间的结构界面，并为其分配不同的材料属性，从而对相邻组件之间的接头进行建模。解出几个数例进行演示。