Joint torque based Cartesian impedance control for the DLR hand

This paper presents a novel joint torque based Cartesian impedance control for the DLR (German Aerospace Center) Hand. The fingertip appears as mechanical impedance when it contacts with an unknown obstacle. The impedance parameters can be adjusted in a certain range as needed in any Cartesian coordinate system. There is no any switching mode between the motions in the free space and in the constraint environment. The paper also gives a detail analysis about the finger's kinematics and dynamics model. Experimental results have verified the effectiveness and robustness of the proposed scheme.