A robust control strategy of redundant manipulator by workspace observer

This paper describes a decoupling force control strategy of redundant manipulator by workspace observer. In general, the calculation process of the redundant manipulator becomes complicated as the number of degree-of-freedom motion increases since the controller includes the pseudo inverse Jacobian matrix. To improve this issue, we develop a simplification method of the inverse kinematics solution including null space calculation by using the transposed Jacobian matrix, and the workspace observer. Here the stable condition of the proposed controller is also shown. Its condition is an important index to construct the stable workspace observer. The validity of the proposed method is confirmed by the numerical and experimental results in the 3 link planar redundant manipulator.