Redundancy Optimization of Hyper Redundant Robots Based on Movability and Assistability

Abstract

This paper describes a new method to utilize redundancy of hyper redundant robots. In order to establish the effectively use of enormous amount of redundancy, both of the all actuators' contribution for the achievement of the target motions and capability for unpredictable target motions in future should be maximized simultaneously. From this point of view, two redundancy utilization strategies are proposed based on the different evaluation indices, the movability index of each joint and the assistability index for target motions. These indices are formulated based on the evaluation of angular distribution of the column vectors of Jacobian matrices on velocity of each joint, including the end-effector. Then joint input are derived based on the improved gradient projection method to optimize the indices simultaneously. Motion control simulations and experiments with a planar 10R serial manipulator demonstrated the effectiveness of the proposed method.