Reducing Travel Moves in Material Extrusion Additive Manufacturing Through Graph Theory

A novel graph-theory driven toolpath generation algorithm for polymer Material Extrusion (MEX) additive manufacturing (AM) that considers process optimization when writing toolpaths is presented. Contemporary toolpath design algorithms are written to prioritize robustness (always reaching a valid solution) and computational cost (time to solution). This novel toolpath generation algorithm, known as GRATER (GRAph Theory based slicER), is a work-in-progress tool that uses graph theory to guarantee a single continuous toolpath (a toolpath with no travel moves) for every closed contour. GRATER reduced travel moves, which create defects within MEX parts particularly those built using pellet-fed MEX, by up to 95% when compared to contemporary slicing softwares. Additionally, GRATER is shown to reduce travel distance by a factor of 3 and build time by 25%.