冗長自由度を有するマニピュレータの逆運動学の高速かつ安定な解法 A Fast and Singularity-free Solution of Inverse Kinematics for Redundant Manipulators
In this paper one deals with the inverse kinematics of serial-link manipulators with redundant DOFs. At first, one proposes a new algorithm to solve the joint rate variables of redundant manipulators in the framework of the weighted generalized inverse of Jacobian. In the proposed algorithm the weights are determined so as to avoid the computational illconditioning during the recursive procedures of computation, which means no off-line task for determining weights is necessary. Some ways of computing the weights are considered and evaluated with respect to condition number in the simulation. The proposed algorithm takes the least additional load to compute the projection operator which projects arbitrary joint rates into the null-space of the end-effector's Cartesian coordinates. It is due to the algorithmic structure of the proposed algorithm in which some variables produced in the process of the generalized inverse of the Jacobian are made use of computing the projection operator. The anthropomorphic type seven DOF manipulator was taken as an example to evaluate the proposed algorithm. Some ways to determine the arbitrary joint rate vectors were considered so as to make the manipulator behave like a human. Simulations also reveal the stable behavior of the manipulator due to the proposed algorithm when the manipulator is indicated to take singular postures.
日本ロボット学会誌 16(5), 721-727, 1998-07-15
The Robotics Society of Japan