Spatial Awareness in Synthetic Vision Systems: Using Spatial and Temporal Judgments to Evaluate Texture and Field of View

Abstract

Objective: This work introduced judgment-based measures of spatial awareness and used them to evaluate terrain textures and fields of view (FOVs) in synthetic vision system (SVS) displays. Background: SVSs are cockpit technologies that depict computer-generated views of terrain surrounding an aircraft. In the assessment of textures and FOVs for SVSs, no studies have directly measured the three levels of spatial awareness with respect to terrain: identification of terrain, its relative spatial location, and its relative temporal location. Methods : Eighteen pilots made four judgments (relative azimuth angle, distance, height, and abeam time) regarding the location of terrain points displayed in 112 noninteractive 5-s simulations of an SVS head-down display. There were two between-subject variables (texture order and FOV order) and five within-subject variables (texture, FOV, and the terrain point's relative azimuth angle, distance, and height). Results: Texture produced significant main and interaction effects for the magnitude of error in the relative angle, distance, height, and abeam time judgments. FOV interaction effects were significant for the directional magnitude of error in the relative distance, height, and abeam time judgments. Conclusion: Spatial awareness was best facilitated by the elevation fishnet (EF), photo fishnet (PF), and photo elevation fishnet (PEF) textures. Application: This study supports the recommendation that the EF, PF, and PEF textures be further evaluated in future SVS experiments. Additionally, the judgment-based spatial awareness measures used in this experiment could be used to evaluate other display parameters and depth cues in SVSs.