Efficient concurrent toolpath planning for multi-material layered manufacturing

S.H. Choi and W.K. Zhu Department of Industrial and Manufacturing Systems Engineering, The University of Hong Kong, Hong Kong Abstract Reviewed, accepted September 10, 2008 This paper proposes an algorithm for planning efficient concurrent toolpaths to reduce the build-time of fabricating multi-material prototypes by layered manufacturing. The algorithm first sorts and partitions slice contours into hierarchical families of specific materials to enhance concurrent tool movements. It then detects overlapping of parametric tool envelopes with a “Two-phase Overlap Query Algorithm” to avoid potential tool collisions. Finally, it plans concurrent movements with an “Immediate Fabrication Algorithm” (IFA) to enhance fabrication efficiency by reducing idle time of tools. The algorithm is being implemented in a multi-material virtual prototyping system. It can be adapted for control of physical fabrication of multi-material prototypes when appropriate hardware becomes available.