Collision-Avoidance Experiments on 7-DOF Robot Arms

A report describes experiments on the concept described in "Real-Time Collision Avoidance for a Robot Arm" (NPO-19861), NASA Tech Briefs, Vol. 20, No. 12 (December 1996), page 98. Under this concept, collision-avoidance software processes data computed by model-based obstacle-detection software to generate perturbations of the trajectory of a robot arm away from the commanded trajectory whenever the commanded trajectory brings the arm within a specified distance from one or more obstacle(s). In computing the perturbation, the software strives to nullify a virtual repulsive force proportional to the incursion of the obstacle plus a virtual damping force proportional to the closing velocity of the arm and the obstacle.