Human-robot cooperative rope turning—an example of mechanical coordination through rhythm entrainment

Abstract

In this paper, we deal with human-robot mechanical coordination through rhythm entrainment. We present a method of realizing cooperative rope turning by a man and a manipulator. The rotating motion of the manipulator arm for rope turning can be specified by the frequency and phase difference between the arm and the rope. The frequency is determined in real-time by rhythm entrainment using a phase-locked loop (PLL). The phase difference is related to the quantity of local interaction, i.e. energy transfer from the arm to the rope. Therefore it is controlled to realize the desired energy transfer, which is estimated from human demonstration. In the experiment the manipulator can successfully adapt its motion to that of the human partner.