Fuzzy avoidance control strategy for redundant manipulators

This paper presents a systematic design method to solve the problem of obstacle avoidance for a redundant manipulator, using a fuzzy-logic system. The pseudo-distance (P_d) function is introduced to measure the distances between the robot and various obstacles; this function can be effectively solved by linear programming. The traditional implementation of obstacle avoidance will result in a hard switching that may cause sudden changes of the joint motion. The proposed fuzzy-avoidance-control strategy can generate a smooth switching from free motion to obstacle avoidance motion, and can provide a soft switching to avoid obstacles. Numerical simulations are demonstrated to show the effectiveness of the proposed approaches. © 1999 Elsevier Science Ltd. All rights reserved.