Safety Methods for Cartesian Control of Redundant Robotic Arms

Over the last years, the interest in robot safety has increased, due to the improvements in applications such as assistive robotics, co-manipulation or manufacturing cobots. In these scenarios that include physical interactions between humans and robots, it is of upmost importance to have both passive and active safety layers that prevent robotic arms to behave in an unsafe manner. Ultimately, the safety measures that can be applied might depend on the sensors installed on a robot. Robots with joint torque sensors often base their safety in reactive behaviors when a contact is detected. However, robots should be able to also have safety layers that do not depend on detected contacts. In this paper, we show several additions to robotic Cartesian controllers that can significantly improve safety in human-robot physical interaction for robots with joint position encoders only.