Obstacle avoidance control for redundant manipulators using collidability measure

We present an efficient obstacle avoidance control algorithm for redundant manipulators using a new measure called collidability measure. Considering moving directions of manipulator links, the collidability measure is define d as the sum of inverse of predicted collision distances between links and obstacles: This measure is suitable for obstacle avoidance since directions of moving links are as important as distances to obstacles. For kinematic or dynamic redundancy resolution, null space control is utilized to avoid o bstacles by minimizing the collidability measure: We present a velocity-bou nded kinematic control law which allows reasonably large gains to improve t he system performance. Also, by clarifying decomposition in the joint accel eration level, we present a simple dynamic control law with bounded joint t orques which guarantees tracking of a given end-effector trajectory and imp roves a kinematic cost function such as collidability measure. Simulation r esults are presented to illustrate the effectiveness of the proposed algori thm.