Mixed Visual and Force Feedback Model of an Upper Limb Motion

Abstract

From the viewpoint of human centered approach, an upper limb motion model is indispensable in order to construct a harmonized human-machine system such as power assist system or collaborater. In a positioning operation, human decides how to move his upper limb after a visual recognition of own operating error from the target. The authors have proposed “the visual feedback model” for the representation of such human behavior. In this paper the issue of the visual feedback model in rapid motion is pointed out theoretically from the aspects concerning the rapid movement and the slow movement in a voluntary motion, and a new “mixed visual and force feedback model” of an upper limb motion is proposed. The model is constructed, as a feedback system to be harmonious with an impedance of upper limb, with both the feedback loop of time delayed visual information and the inner feedback loop of no-delayed force information. The positioning experiment was performed for the single-link manipulator with the virtual indicating needle. And it is shown that the proposed model much improves the representation of human behavior in the rapid movement. Finally, from the viewpoint of operation force the validity of the proposed model is also confirmed.