Joint Torque Minimization of Redundant Manipulator by Bracing Control.

In this paper, a performance improving method by the constraint of the intermediate point of the redundant manipulator with the environment is presented. In general, the redundant manipulator is useful to avoid collisions and carries out the motion in which the position of endpoint and whole posture avoids the obstacle. Though it is possible that the manipulator can change the posture by adjusting the redundant degree of freedom, simultaneously, the saturation of the joint torques occurs, and the error at the end point increases with the increase in components. In order to solve that problem, we propose the bracing control method. Bracing control is to contact the intermediate point of redundant manipulator at the environment surface, and can use the contact force as the equivalent control input. By bracing control, it can be expected that the joint torques is compensated. It is examined by an experiment using industrial manipulator how the joint torques is able to be saved using proposed method.