Feasible Build Orientations for Self-Supporting Fused Deposition Manufacture: A Novel Approach to Space-Filling Tesselated Geometries

Abstract

Support material is often utilised in additive manufacture to enable geometries that are not otherwise self-supporting. Despite the associated opportunities for innovation, the use of support material also introduces a series of limitations: additional material cost, cost of removal of support material, potential contamination of biocompatible materials, and entrapment of support material within cellular structures. This work presents a strategy for minimising the use of support material by comparing the geometric limits of an additive manufacture process to the build angles that exist within a proposed geometry. This method generates a feasibility map of the feasible build orientations for a proposed geometry with a given process. The method is applied to polyhedra that are suitable for close packing to identify space-filling tessellated structures that can be self-supporting. The integrity of an FDM process is quantified, and using the associated feasibility map, self-supporting polyhedra are manufactured. These polyhedra are integrated with non-trivial geometries to achieve a reduction in consumed material of approximately 50%. Nomenclature

Additive manufacture of custom radiation dosimetry phantoms: An automated method compatible with commercial polymer 3D printers

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“…This discrete manufacturing strategy inherently results in resolution errors [32]. These errors are a function of layer thickness, machine, material and post processing, and must be accounted for in medical applications [33,34].…”

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“…Only few designs focused on the macrostructure parts. One great obstacle is that the support structures are generally imported in the SLM process as there are some technical constraints and design rules for SLM, such as the minimum feature size, the manufacturing inclination angle and the allowable overhang distance [8,10]. Some studies have been conducted to investigate design constraints.…”

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