A multi-material virtual prototyping system for product development and biomedical engineering

Abstract

This paper proposes a multi-material virtual prototyping (MMVP) system that integrates the virtual reality (VR) and the layered manufacturing (LM) technologies for digital fabrication of heterogeneous multi-material prototypes for advanced product development and biomedical engineering. The system consists mainly of two algorithms for sequential and concurrent multitoolpath planning, and a virtual prototyping system. The algorithms adopt a topological hierarchysorting algorithm to establish the hierarchy relationship of multi-material slice contours for facilitating toolpath planning of multi-material layered manufacturing (MMLM). Subsequently, the sequential multi-toolpath planning algorithm generates sequential toolpaths that avoid redundant tool movements. To reduce build time further, the concurrent multi-toolpath planning algorithm generates collision-free concurrent toolpaths. Based on the hierarchy information, a bounding box can be adopted to approximate envelopes of contour families of the same material property to simplify detection of tool collisions. The algorithms are integrated to form the MMVP system for planning, stereoscopic simulation, and validation of multi-toolpaths for MMLM.