Static and dynamic forces accuracy of a Lightweight Collaborative Robot through impedance control

Industry 4.0 has become established, arousing the great interest of curiosities and fears for the impact not yet recognized. Human-robot collaboration is also being given more emphasis since collaborative robots improve safety and flexibility. However, not for all possible applications, the great initial economic effort of these machines may pay off expectations. This dissertation aims to give useful measurements performed on a KUKA LBR iiwa, an advanced collaborative robot. By executing particular tasks, like polishing, it has been noticed that Cartesian forces reconstructed by the robot are not always such accurate as assured by the manufacturer. The goal of this thesis is to compare the measured force by the robot torque sensors with the force measured by an external load cell. The focus is on the Z-axis force, considered the most relevant for the applications considered. For this reason, a commercial mono-axial load cell has been used. In these experiments, both static and dynamic forces were treat.