Effects of unlimited angular motion cue and cue discrepancy on simulator sickness

Abstract

Simulator sickness is a crucial concern undermining several benefits of simulator training, such as a realistic environment, low costs, and safe practice of emergencies. This study investigated the effects of unbounded angular motions and visual-vestibular cue discrepancies on simulator sickness for flight simulator training. Human subject experiments with 36 participants demonstrated that simulator sickness, measured by questionnaires and physiological signals, was significantly decreased by offering both motion and visual cues rather than visual signals alone (p < 0.05). Specifically, nausea (without motion = 54.59, with motion = 31.27; p = 0.036) and disorientation scores (without motion = 81.20, with motion = 44.08; p = 0.028) significantly decreased when both motion and visual signals were present. Furthermore, the experimental results showed a significant correlation between simulator sickness and visual-vestibular cue mismatches, particularly for the angular velocity along the z-axis (r = 0.110, p = 0.04). The pitch angle discrepancy (r = 0.156, p = 0.004) between the visual and motion cues was significantly correlated with the sickness severity, unlike the roll angle disparity (r = −0.009, p = 0.871). The results from this study can be explored for flight training operations using motion simulators to minimize or eliminate simulator sickness.