Beyond layers: A 3D-aware toolpath algorithm for fused filament fabrication

Fused filament fabrication (FFF) is gaining traction for rapid prototyping and custom fabrication. Existing toolpath generation methods for FFF printers take as input a three-dimensional model of the target object and construct a layered toolpath that will fabricate the object in 2D slices of a chosen thickness. While this approach is computationally straightforward, it can produce toolpaths that can contain significant, yet unnecessary, extrusionless travel. In this paper we propose a novel 3D toolpath generation paradigm that leverages local feature independence in the target object. In contrast to existing FFF slicing methods which print an object layer by layer, our algorithm provides a means to print local features of an object without being constrained to a single layer. The key benefit of our approach is a tremendous reduction in “extrusionless travel,” in which the printer must move between features without performing any extrusion. We show on a benchmark of 409 objects that our method can yield substantial savings in extrusionless travel, 34% on average, that can directly translate to a reduction in total manufacturing time.