Does individual stereo acuity affect performance using stereo 3D in a Helmet Mounted Display?

摘要

A pilot's Helmet-Mounted Display (HMD) is now a critical part of the aircraft system. Next generation HMDs will be able to display information and imagery binocularly, with stereoscopic depth. Stereo 3D (S3D) can potentially be used to enhance situational awareness and improve performance. The degree to which performance is improved may be linked to individual visual capabilities of the user, in particular, stereo acuity. Stereo acuity varies tremendously in the general population with up to 30% being classed as 'stereo blind'. For most military aviators there is a minimum stereo acuity standard, however current test methods are crude and fallible. Many previous S3D studies do not accurately characterize individual stereo acuity, and in some cases do not even screen for its presence, making their results difficult to interpret. The Operational Based Vision Assessment (OBVA) laboratory has developed a flight simulation platform using an SA Photonics SA-62 HMD to display stereoscopic symbology and five 85-inch displays to provide the "out the window" view. After completing a battery of vision tests, participants fly various mission profiles while responding to a combination of navigational instructions and warning alerts displayed in the HMD. The warning alerts are displayed in 2D (flashing at 1 Hz), intermittent S3D (flashing on and off at depth), persistent S3D (alternating between 2 depth planes), and dynamic S3D (motion in depth). We present preliminary data examining whether a stereoscopic HMD could be used to improve performance when responding to a critical warning alert, and discuss potential implications for military aviator vision standards as well as HMD requirements.