Abstract
We studied orientation-dependent vibrotactile feedback (VF) as a countermeasure to spatial disorientation (SD) in spaceflight analog environments. In Experiment 1, participants balanced themselves in a dynamic motion simulator in Earth (1-g), Martian (0.38-g), Lunar (0.166-g) and 0-g analog conditions. One group (n = 13) had VF and the Control group (n = 13) did not. As g-level decreased, attitude control and subjective confusion worsened, for both groups. An exponential model fit both groups. The Control group became significantly worse than its 1-g baseline at 0.61 to 0.23-g. Based on these model fits, the VF group performed slightly better than Controls in 1-g, significantly better between 0.82 and 0.10-g, and their performance advantage increased towards 0-g. However, both groups reported similar levels of confusion in their sense of angular position and velocity across all g-levels. The VF group reported high trust in VF cueing as g-level decreased, despite their worsening performance and subjective confusion, highlighting a dissociation between the effectiveness of VF and cognitive trust in VF. Despite its benefits during hypo-g exposures, VF did not fully restore 1-g proficiency. In Experiment 2, we assessed whether a new group (n = 13) of participants given extended exposure with VF in the Lunar analog condition would achieve 1-g level performance. Initial performance and confusion deteriorated significantly relative to 1-g but then improved significantly until 1-g baselines were restored for most measures. However, signatures of SD, including attitude drift and positional confusion were still present. These results suggest that VF potentially would enhance dynamic vehicle control in spaceflight but may not fully eliminate SD.