Control of Human-Robot Interaction Flexible Joint Lightweight Manipulator Based Joint Torque Sensors

Abstract

Recently, flexible joint lightweight robots are widely used in a variety of mobile robots or mechanical platforms, playing a more and more important role in the areas of space exploration, military reconnaissance, counter-terrorism, defusing, as well as home service. From the viewpoint of lightweight robot applications, there exist many different tasks under changing working conditions, either working in dangerous and unknown complex environment or closely contacting with human beings. Therefore, for a safe operation and high reliability, lightweight robots need not only high-precision position control but also compliance control, such that no injury on the robot and operated object will occur when interacting with the unknown environments. In order to make the manipulator contacts the environment compliantly, and reduces the instantaneous impact when collision occurs. This paper presented an interaction impedance control strategy for manipulator based on joint torque sensor, and combined with the trajectory regeneration with force feedback. Experiment was performed on a 5-DOF flexible joint lightweight manipulator. The experiment results of tapping on an egg showed the manipulator contacts the object compliantly and reduces collision impact, so the proposed approach was effectiveness and validity.