21 June 2019

Thibault Tricard, Frédéric Claux, Sylvain Lefebvre

Computer Graphics Forum, 2019

Additive manufacturing techniques form an object by accumulating layers of material on top of one another. Each layer has to be supported by the one below for the fabrication process to succeed. To reduce print time and material usage, especially in the context of prototyping, it is often desirable to fabricate hollow objects. This exacerbates the requirement of support between consecutive layers: standard hollowing produces surfaces in overhang that cannot be directly fabricated anymore. Therefore, these surfaces require internal support structures. These are similar to external supports for overhangs, with the key difference that internal supports remain invisible within the object after fabrication. A fundamental challenge is to generate structures that provide a dense support while using little material. In this paper, we propose a novel type of support inspired by rib structures. Our approach guarantees that any point in a layer is supported by a point below, within a given threshold distance. Despite providing strong guarantees for printability, our supports remain lightweight and reliable to print. We propose a greedy support generation algorithm that creates compact hierarchies of rib-like walls. The walls are progressively eroded away and straightened, eventually merging with the interior object walls. We demonstrate our technique on a variety of models and provide performance figures in the context of Fused Filament Fabrication (FFF) 3D printing.

Paper available on HAL

Below is a link to a Windows binary (64 bits) that can be used to generate the supports.

Authors: Frédéric Claux and Thibault Tricard

Requirements: a 64-bit Java 8 or later Virtual Machine needs to be installed on your computer. If both a 32-bit and a 64-bit JVM are installed on your computer, the 64-bit JVM must be the default JVM. The application also requires an OpenGL 4.3 graphics card and a recent graphics driver. Any graphics card manufactured after 2010 should work. You must agree with the terms listed in the About dialog prior to using the application for support generation.

Buddha cube bottom cuteOcto cuteocto topview kitten2 moai transparent