Variable viscoelasticity handshake manipulator for physical human–robot interaction using artificial muscle and MR brake

In this study, a handshake manipulator with variable viscoelastic joints was proposed. The variable viscoelastic joint system comprised of antagonized artificial muscles and a magneto-rheological fluid brake. This joint system resembles the characteristic of real human joint. The objective of this study is to evaluate the proposed manipulator's effectiveness in the research of human–robot physical interaction and to verify that by adjusting the viscosity and stiffness of the joint it is possible to create handshakes with different feelings. In this research two sets of experiments were conducted; the first set of experiments was to conducted on the manipulator alone in order to test the performance of the manipulator. And the second set of experiments was the subjective evaluation of the manipulator when subjects shook hand with the manipulator under variable viscosity and stiffness conditions. The results of these experiments indicated that the manipulator was suitable for doing research on human–robot handshake, and the variable viscosity and stiffness of the elbow joint did create distinctive feelings to the subjects. (paper)