New collision detection method for CSG-represented objects in virtual manufacturing

In virtual manufacturing environment, operator-system interactions and physical simulation require real time collision detection. A fast and precise algorithm for collision detection is therefore critical to ensure the usability of virtual reality (VR)-based manufacturing simulation. This paper proposes an efficient and precise collision detection algorithm for constructive solid geometry (CSG) represented objects in a virtual environment. It mainly takes advantages of the CSG `divide-and-conquer' paradigm and efficient distance-aided collision detection for convex bounding volumes. An adaptive selection strategy for optimal bounding volumes of sub-trees of objects is used to realize a fast localization of possible collision regions at each detection step, and decision rules for sub-tree freezing and result evaluating are created. Performances of the applications used in a virtual training system for CNC milling machine manual operations and virtual assembly operations have demonstrated the effectiveness of the proposed methodology.