Support-Free Volume Printing by Multi-Axis Motion

The method enables support-free 3D printing of solid models. By exploiting all 6 degrees of freedom (translations, rotations) and depositing material along curved layers, we make support structures unnecessary in most cases. This increases further the flexibility offered by 3D printing, such as freeing designers from support constraints on complex parts.

This paper presents a new method to fabricate 3D models on a robotic printing system equipped with multi-axis motion. Materials are accumulated inside the volume along curved tool-paths so that the need of supporting structures can be tremendously reduced – if not completely abandoned – on all models.

Our strategy to tackle the challenge of tool-path planning for multi-axis 3D printing is to perform two successive decompositions, first volume-to-surfaces and then surfaces-to-curves. The volume-to-surfaces decomposition is achieved by optimizing a scalar field within the volume that represents the fabrication sequence.

The field is constrained such that its iso values represent curved layers that are supported from below, and present a convex surface affording for collision-free navigation of the printer head. After extracting all curved layers, the surfaces-to-curves decomposition
covers them with tool-paths while taking into account constraints from the robotic printing system. Our method successfully generates tool-paths for 3D printing models with large overhangs and high-genus topology. We fabricated several challenging cases on our robotic platform to verify and demonstrate its capabilities.

Download the Paper PDF: Support-Free Volume Printing by Multi-Axis Motion

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