Cartesian impedance control for the DLR Hand

Presents a novel Cartesian impedance control for the DLR (German Aerospace Center) Hand based on joint torque measurements. 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 switching mode between the motions in the free space and in the constraint environment. The paper also gives a detailed analysis of the finger's kinematics and dynamics model. Experimental results have verified the effectiveness and robustness of the proposed scheme.