Compliant Control Based on Stability Observer for Physical Human-Robot-Environment Interaction

This paper proposes an improved stability observer to obtain the interaction state in real-time for physical human-robot-environment interaction (pHREI). Firstly, a stability observer is designed to effectively avoid the misjudgment caused by the phase advance or delay of the filter. Then, the variable admittance control algorithm is designed according to the value of the observer. Finally, a comparative experiment is carried out. The results show that the proposed method can effectively reduce the oscillation when the operator drags the robot into contact with the environment.