Safe physical human-robot interaction with industrial dual-arm robots

This paper presents methodologies and tests for the safe physical human-robot interaction in conventional position controlled and non-back driveable industrial robotic systems. The developed algorithms are based on a simplified sensor-less estimation of external forces and saturation of joint control torques to keep the effective external forces under safety level. To cope with non-linear saturation phenomena, position control compensators and path error governor have been implemented and designed to ensure smooth behaviour and preserved control performance. Being able to stop the robot arm motion when applying risky forces, as recommended by ISO 10218, the human feels subjective safe in the robot vicinity. Experiments with the PISA Workerbot dual-arm robot system illustrate feasibility and robustness of the developed algorithms.