Resolved control of cooperative manipulators based on virtual force transmission algorithm

In general approach, the inverse kinematics of a manipulator has been determined by solving the kinematic equation using Jacobian matrix. However in case a link number is large, the calculation of the inverse kinematic solution becomes so complicated. Furthermore the method based on Jacobian matrix is lacking in the flexibility against the transformation of manipulator's structure. To improve this issue, this paper proposes a novel approach which does not use Jacobian matrix. In this method, the generating force is resolved from the tip to the base joint of a serial link manipulator step by step. Then the virtual force transmission is considered instead of Jacobian matrix. Since the method is independent of the kinematics of the manipulator, the method depends on only the neighboring joints and the controller. This is one of the remarkable points of the proposed approach to realize the simple and decentralized controller in the multiple DOF motion system such as plural and cooperative manipulators. This paper adopts the proposed method to the redundant manipulator and the cooperative manipulator. Furthermore, this paper succeeded to control the grasped object with its own frame directly. The efficiency of this approach is confirmed through some numerical simulations and experiments.