Presentation of Robot-Intended Handover Position using Vibrotactile Interface during robot-to-human handover task

Advancements in robot autonomy and safety enable close interactions such as object handovers with a human. During robot-to-human handovers in assembly tasks, the robot considers the human's state to determine the optimal handover position and timing. However, humans may struggle to focus on their primary tasks due to the need to track the robot's movement. This research aims to develop a vibrotactile interface that helps humans maintain focus on their primary tasks during object-receiving. The interface conveys the robot-intended handover position on the human's forearm in polar coordinates, displaying the angular direction and distance relative to the human hand via vibrations. Experimental results demonstrated that this method allowed participants to receive objects with faster reactions and completion time. Subjective evaluations reveal a perception of improved performance and reduced mental workload compared to baseline making the robot-to-human handover smoother and less distracting.