COLLISION DETECTION OF MANIPULATOR ARMS WITH COMPLEX LINKS

摘要

A method for detecting collision of manipulator links is presented and used to avoid collision in a robotics environment in which manipulator links and obstacles are represented by complex solids. Surface boundary representation methods are used to envelop each solid with a known surface (ruled, double curved, surface patches, and planar surfaces). Negative entities are defined on surfaces having discontinuities. Based on this representation scheme, a collision detection method is developed that incorporates complex solids. The collision avoidance algorithm is based on checking the surfaces of solid pairs of bodies for interference. The intersection curve (or branch) is calculated and checked for existence inside the boundary of entities on the two surfaces. Each segment of the intersecting curve is analyzed by introducing a new method for determining the existence of a point inside the boundary of an entity. This method is based upon computing the circulation along a closed contour of a surface. Boundary curves using this method need not be convex or simply connected. The theory presented is implemented into a computer program and used to detect collisions of a six-axis manipulator arm.