Redundancy resolution for the human-arm-like manipulator

The human-arm-like manipulator has a seven-degree-of-freedom kinematic structure obtained by adding a roll joint to the shoulder of the PUMA geometry. This mechanism has higher dexterity than conventional six-degree-of-freedom arms, and allows the elimination of the internal singularities at the shoulder and the wrist. The contribution of the present work is to exploit redundancy to accomplish singularity avoidance and possibly recover the original PUMA design. The inverse for kinematics problem is solved at the velocity level by means of a closed-loop algorithm in the framework of task space augmentation with task priority. Three case studies demonstrate the effectiveness of the proposed technique.