Performance analysis of a manipulation task in time-delayed teleoperation

There is ample research on the stabilization of haptic teleoperation systems under communication time delay. Little attention, however, has so far been paid to the usefulness of delayed haptic feedback on task performance. While the usefulness of haptic feedback in no-delay teleoperation has been previously established, this paper investigates whether haptic feedback helps to improve task performance in the presence of delay. We consider peg-in-the-hole insertion, which is a dexterous manipulation task requiring high force levels at certain points during the task execution. Through a user study involving unilateral and bilateral teleoperation experiments under different delays, it is observed that in both unilateral and bilateral teleoperation, the task completion time increases as delay increases. It is also seen that haptic feedback helps reduce the amount and rate of energy transfer to the environment and the occurrence of larger robot/environment interaction forces. However, with the users mindful of minimizing contact forces, haptic feedback causes the task to take more time compared to no haptic feedback regardless of the time delay. Thus, for tasks where low completion times are crucial given a tolerance for larger forces, unilateral feedback may be sufficient.