A Compliant Human Following Method for Mobile Robot Based on an Improved Spring Model

For the automated guided vehicle with human-following function in human-machine integration environment,a compliant following method of mobile robot based on an improved spring model is proposed to solve the problem of robotmalfunction caused by abrupt movements of the followed target. The closed-loop control of the relative posture between themobile robot and the followed target is performed by adding virtual springs to the legs of the followed target and obstaclesto accomplish obstacle avoidance and natural interaction tasks. In particular, dynamic damping coefficients are added tothe virtual spring to make the mobile robot follow the human target compliantly in real time. In Simulink simulation, thecompliant following trajectory of the mobile robot is compared with the dynamic motion of the target, and thus the optimalparameters of the spring model are obtained. A self-developed two-wheeled differential mobile robot and an optical motioncapture system are utilized to verify the smoothness and flexibility of the mobile robot trajectory when the followed humantarget performs irregular and long-distance motion.