Strategy Development Pilot Study of Sleep-Restricted Operators Using Small Satellites with Displays

INTRODUCTION: Sleep restriction may lead to decreased performance and increased accidents and errors. SPHERES, a small satellite testbed, was used to examine the effects of sleep restriction and situation awareness (SA) aids on a simulation of satellite operations. METHODS: Subjects (N = 8) were trained on SPHERES, then, in a randomized order cross-over design, had 3 d of sufficient sleep (SS) or 3 d of sleep restriction (SR) before a testing session. Subjects controlled two SPHERES satellites in a space debris avoidance scenario. Dependent measures included survival time, area covered by the satellites, and satellite motion perception. RESULTS: There were significant interaction effects of sleep protocol Order (SS or SR first) and sleep Condition (SS or SR) on survival time and area covered. Post hoc tests showed longer survival time for the second testing session if the Order was SS first (Mean = 56.1 s, Median = 44.0 s) as compared to SR first (Mean = 42.7 s, Median = 33.5 s). SS-first subjects received benefit from added SA cues of the augmented display in perceiving the satellite motion. DISCUSSION: These data support that learning in a well-rested state may support development of appropriate strategies for better performance. Subjects that were SS during the first session were better able to use added SA cues provided by the augmentation and may have then developed a better mental model of the task and the system. This pilot study suggests that training guidelines for operating multiple robotic assets should permit appropriate rest before and after training to assist in mental model development and task performance.