ADAPTIVE PATH PLANNING AND OBSTACLE AVOIDANCE FOR A ROBOT WITH A LARGE DEGREE OF REDUNDANCY

A new algorithm for path planning and obstacle avoidance for redundant planar robots is proposed. The task of path planning is formulated as a sequence of nonlinear programming problems. For each problem, the o bjective is to minimize the distance between the current location of t he end-effector and a desired location. Two penalties are added to eac h objective function to ensure that the robot is not colliding with an y obstacle and that its links are not crossed over. The effects of mec hanical stops and limits for maximum joint movements are also incorpor ated as inequality constraints. The algorithm uses an adaptive scheme to activate the fewest number of the outboard-most joints, and none of the inboard ones if possible, to reach a desired location. The algori thm is especially useful when the number of joints is large. (C) 1996 John Wiley & Sons, Inc.