Low-force kinesthetic guidance for accurate positioning and tracking

This paper considers the application of a low-force robotic manipulator to guide a human user's movement to locate a tool at a predetermined position or to move a tool along a predetermined trajectory. In this application, the guidance must be sufficiently smooth because the user's force can easily overcome the guiding force. The proxy-based sliding mode control, which we previously proposed, is capable of achieving a smooth overdamped convergence to a given position, without overshoots, with a limited actuator torque. This paper proposes the application of the proxy-based sliding mode control to low-force kinesthetic guidance. Experimental results demonstrate the effectiveness of this application, showing that the time constant of the guidance control should be set around 0.1 sec rather than 0.01 sec or 0.5 sec.