Abstract: A new hybrid index dynamic obstacle avoidance algorithm for redundant manipulator is proposed. Considering the randomness of the moving obstacle, the shortest distance index is used as the index of the obstacle avoidance planning based on gradient projection method when the moving obstacle is inside the configuration of the manipulator. When the moving obstacle is outside the configuration, the obstacle avoidance area index is used to substitute for the invalid shortest distance index. Through using the hybrid index, the combination of fine adjustment and coarse adjustment for the configuration of the manipulator is realized. And the effect of the whole obstacle avoidance is improved. In addition, the problem of exceeding the joint velocity limit can be solved by the on-line adjustment of the magnification factor, so as to keep a constant ratio between null-space-solution and minimum-norm-solution. The algorithm is illustrated by a planar 3R2P redundant manipulator. The simulations of comparison between single index planning and hybrid index planning show superiority and effectiveness of the latter. And the real object experiments prove the real-time performance and universality of the algorithm.

Key words: Dynamic obstacle avoidance planning, Hybrid index, Magnification factor, Redundant manipulator