Extended generalized impedance control for redundant manipulators

An impedance control method for redundant manipulators called an extended generalized impedance control is developed. It is based on an extended task space formulation and generalized impedance control. With generalized impedance control, the manipulator's end-effector position and force tracking abilities can be balanced by properly adjusting impedance parameters. Null space motion is controlled by tracking a minimal parameterization of null space velocity. Redundancy is then exploited by specifying a desired null space velocity trajectory that optimizes a performance index. The control algorithm is implemented as part of OSCAR (Operational Software Components for Advanced Robotics), keeping with the generality concept. Therefore, it can be easily deployed with any serial manipulator. The effectiveness of the proposed controller is illustrated by computer simulations of a complex 10-DOF spatial manipulator performing a cutting task.