Joint Stiffness Identification of a Heavy Kuka Robot with a Low-cost Clamped End-effector Procedure

Abstract

This paper proposes two new methods for the identification of static stiffnesses of multi degrees of freedom heavy industrial robots. They are based on a locked link joint procedure obtained with an end-effector fixed to the environment. The first method requires only measurements of motor positions and motor torques data computed from motor current measurements and manufacturer's drive gains. The second one needs a torque sensor to measure the interaction wrench between the clamped end-effector and the environment. These methods are being experimentally validated and compared on the 2 first joints of a 6 degrees of freedom heavy 500Kg payload industrial Kuka KR500 robot.