In haptics, the influence of the controllable physical damping on stability and performance

Physical damping is essential to achieve passivity in haptic display. To improve stability, an additional physical damper was used with motor. This fixed damping approach, however, has limitation to display free motion, so that the motor actually has to work for damping cancellation. This paper suggests that the controllable damping approach without necessity for damping cancellation to improve both stability and performance. Firstly, we analyze the effect of the controllable physical damping on stability and also propose a controllable physical damping approach applying controllable magnetorheological brake to haptic display. Finally, we experimentally show the contribution of the proposed controllable physical damping approach to the performance in terms of Z-width.