ABSTRACT

Additive Manufacturing (AM) processes intended for large-scale components deposit large volumes of material to shorten process duration. This reduces the resolution of the AM process, which is typically defined by the deposition nozzle size. If the resolution limitation is not considered when designing for Large-Scale Additive Manufacturing (LSAM), difficulties can arise in the manufacturing process, which may require the adaptation of deposition parameters. This work incorporates the nozzle size constraint into Topology Optimisation (TO) in order to generate optimised designs suitable to the process resolution. This article proposes and compares two methods, which are based on existing TO techniques that enable control of minimum and maximum member size, and of minimum cavity size. The first method requires the minimum and maximum member size to be equal to the deposition nozzle size, thus design features of uniform width are obtained. The second method defines the size of solid members sufficiently small for the resulting structure to resemble a structural skeleton, which can be interpreted as the deposition path. Through filtering and projection techniques, the thin structures are thickened according to the chosen nozzle size. Thus, a topology tailored to the deposition nozzle size is obtained along with a deposition proposal. The methods are demonstrated and assessed using 2D and 3D benchmark problems.

摘要

旨在用于大型组件的增材制造（AM）工艺会沉积大量材料，以缩短工艺时间。这降低了AM处理的分辨率，该分辨率通常由沉积喷嘴的尺寸来定义。如果在设计大规模增材制造（LSAM）时未考虑分辨率限制，则制造过程可能会出现困难，这可能需要调整沉积参数。这项工作将喷嘴尺寸约束纳入拓扑优化（TO）中，以生成适合过程分辨率的优化设计。本文提出并比较了两种方法，它们基于现有的TO技术，可以控制最小和最大构件尺寸以及最小空腔尺寸。第一种方法要求最小和最大构件尺寸等于沉积喷嘴的尺寸，从而获得均匀宽度的设计特征。第二种方法定义了实体构件的尺寸，该尺寸要足够小，以使所得结构类似于结构骨架，这可以解释为沉积路径。通过过滤和投影技术，可以根据选定的喷嘴尺寸来加厚薄结构。因此，获得了适合于沉积喷嘴尺寸的拓扑结构以及沉积方案。使用2D和3D基准测试问题演示并评估了这些方法。可以解释为沉积路径。通过过滤和投影技术，可以根据选定的喷嘴尺寸来加厚薄结构。因此，获得了适合于沉积喷嘴尺寸的拓扑结构以及沉积方案。使用2D和3D基准测试问题演示并评估了这些方法。可以解释为沉积路径。通过过滤和投影技术，可以根据选定的喷嘴尺寸来加厚薄结构。因此，获得了适合于沉积喷嘴尺寸的拓扑结构以及沉积方案。使用2D和3D基准测试问题演示并评估了这些方法。