Haptics in Between-Person Object Transfer

Although object handover between people is a commonly performed task, little about underlying control mechanisms is known. The present study examined haptic contributions in object handover. On each trial one participant held an object and passed it to the other participant at self-selected, fixed or randomly varied positions. In some trials, the receiver wore a glove to attenuate tactile information. The results showed that the passer’s time of grip release relative to contact was later when the transfer location randomly varied or when the receiver wore the glove. On the other hand, forces at contact dropped across trials with negligible effects of glove or transfer location. In conclusion, the present study demonstrated that the dyad reduced redundant forces at contact by forming a stereotypical handover movement in a feedforward manner, while the sensory feedback modulates timing of object handover to avoid premature release of grip by the passer.