Tactile Apparent Motion Through Human-Human Physical Touch

We investigate the effects of vibrotactile feedback from a hand of a partner as a medium of vibration propagation. By controlling the vibrotactile feedback provided on wrists, a tactile apparent motion can be induced between hands of a pair holding each other. Two experiments were conducted to demonstrate the tactile apparent motion. In the first experiment, we measured intensity of the vibration propagated from a bracelet device on the wrist to the hand. The result shows that the vibration on one hand is perceivable by the other person. In the second experiment, we measured the range of stimulus onset asynchrony (SOA) that induces a continuous motion between the hands under a constant duration of vibration (d). The psychophysical experiment shows that the tactile apparent motion is observed when (d, SOA) is around either (120, 80) or (240, 120) milliseconds. The paper discusses the present results in a context of augmenting awareness of touch communication describing our future direction of the research.