A digital input shaper for stable and transparent haptic interaction

This paper presents a frequency-dependent digital damping referred to a digital input shaper (DIS). Compared to the previously proposed analog input shaper, the DIS makes the implementation of damping much more flexible and significantly reduces the electrical noise. Moreover, the DIS can incorporate position control at the initial contact with virtual objects to improve the perceived contact hardness. Through benchmark virtual wall experiments, we show that the DIS can significantly increase the impedance range that a haptic interface can stably display, and that the initial contact hardness that a user perceives can be noticeably improved by using the proposed position control method.