Impact of communication delay and temporal sensitivity on perceived workload and teleoperation performance

As teleoperated robotic units operate in remote and distant environments such as outer space, the communication latency impacts the operator’s performance. Yet, the delay impact on teleoperation performance and mental workload has scarcely been evaluated. Human temporal sensitivity appears to modulate the impact of latency on operators’ performance but no joint assessment of temporal sensitivity and subjective workload has been reported. In this study, we assess the relationship between the impact of communication delay on teleoperation performance, mental workload, and operators’ temporal sensitivity. Sixteen participants completed two online tasks: a duration reproduction task in which they were asked to reproduce the duration of previously presented visual stimuli, and an egocentric maze navigation task which required participants to escape a static maze, under an input latency of 0, 400, and 3000 ms. Completion time, move count, and error rate were recorded for each trial, along with perceived workload using the NASA-TLX questionnaire. The results showed that performance was significantly deteriorated by an increase in communication delay. Moreover, participants’ self-rated performance decreased with a larger communication delay, while their reported frustration, effort, and mental demands significantly increased. Interestingly, a possible effect of the temporal sensitivity profile on teleoperation performance - number of moves - was found, with a reduced number of moves for sensitive participants compared to insensitive ones, following a speed/accuracy trade-off (yet not significant). Hence, different operators’ strategies were uncovered, depending on their temporal sensitivity profile, to mitigate the impact of communication delay on the mission outcome.