Human Systems Integration Division @ NASA Ames

Many factors affect the suitability of an out-the-window simulator visual system. Contrast, brightness, resolution, field-of-view, update rate, scene content and a number of other criteria are common factors often used to define requirements for simulator visual systems. For the past several years, NASA has worked with the United States Air Force (USAF) on the Operational Based Vision Assessment Program (OBVA). The purpose of this program has been to provide the USAF School of Aerospace Medicine (USAFSAM) with a scientific testing laboratory to study human vision and testing standards in an operationally relevant environment (i.e., a research simulator). Requirements for the visual system include high luminance, a large field-of-view, a large color gamut capable of reproducing aviation red, green, and blue, a limited development budget, and a flexible design to support future technology insertion and upgrades. One of the more challenging requirements in designing the reconfigurable image generator was the resolution requirement - approximately 0.5 arc-minutes per pixel, roughly equivalent to 20/10 visual acuity. In addition to static resolution, dynamic resolution (i.e., the perceived resolution of moving imagery) was also investigated to determine how best to minimize motion artifacts in the visual system. In this paper, we will describe how the simulator specifications were developed in order to meet the vision research objectives of USAFSAM, the various design considerations, and the resulting architecture. In particular, we will discuss the image generator architecture and describe the latest performance results along with the unique challenges of developing a visual system that provides eye limited resolution.