Decentralized robust interaction control of modular robot manipulators via harmonic drive compliance model-based human motion intention identification

In this paper, a human motion intention estimation-based decentralized robust interaction control method of modular robot manipulators (MRMs) is proposed under the situation of physical human-robot interaction (pHRI). Different from traditional interaction control scheme that depends on the biological signal and centralized control method, the decentralized robust interaction control is implemented that using only position measurements of each joint module in this investigation. Based on the harmonic drive compliance model, a novel torque-sensorless human motion intention estimation method is developed, which utilizes only the information of local dynamic position measurements. On this basis, the decentralized robust interaction control scheme is presented to achieve high performance of position tracking and ensure the security of interaction to create the 'safety' interaction environment. The uniformly ultimately bounded (UUB) of the tracking error is proved by the Lyapunov theory. Finally, pHRI experiments confirm the effectiveness and advancement of the proposed method.