Spatial disorientation during flight is among the causes of aircraft mishaps with aircraft and pilot losses. In this study, postural responses were used for indicating relative effectiveness of wide-angle visual flow display characteristics in determining perceived spatial orientation. The general experimental setup included a 150A,A deg. x 34A,A deg. wide-field display showing flight over computer-generated ground with horizon. Postural responses were measured by means of a head-tracker system while three integrated computer monitors displayed a wide field of view of ground and horizon as if viewed from a rolling aircraft. Researchers designed two experiments, with 16 participants in each, to investigate the effects of visual flow, display exclusions in the central visual field, and display extensions into the visual periphery. The results of both experiments were quite consistent. The flight-maneuver-adapted flow was effective in inducing postural sway, and the sway varied depending on the visual information that was provided. Clear vestibular and proprioceptive suppression effects were observed on postural sway with the inclusion of visual flow of forward ego motion in roll maneuvers. Compared with the full view, up to 20 degrees x 20 degrees central field omission either did not reduce the effect or reduced the effect frequently, but only moderately. Limiting the display area to 45 degrees in the horizontal dimension significantly reduced display effectiveness, whereas a 105 degrees area did not, compared with the full view. By using postural responses as indications of visual display resonance with the spatial orientation mechanism, applications of this research can include the design of an interface that integrates flight-adapted visual flow to reduce pilot spatial disorientation. This study represents the first steps towards an interface design that integrates visual flow.
Samenvatting