Spatial Awareness with a Helmet-Mounted Display

Two experiments were conducted to determine the human's ability to acquire and memorize the spatial locations of stimulus targets using a helmet-mounted display. The experimental task was a two-phase search and replace task in which the size of the field-of-view (FOV) on the helmet-mounted display and the memory load (number of targets) were manipulated. In Experiment 1, all stimulus targets were removed after the search phase. In Experiment 2, only the three stimulus targets to be replaced were removed, leaving the subjects with some contextual information regarding the overall pattern of targets. Results of both experiments showed that: 1) search time increased significantly as the size of the FOV became smaller, and 2) subjects' ability to replace a stimulus target in its original location in space was adversely affected by increases in memory load. These results indicate that the size of the FOV affects one's ability to acquire spatial information of one's surroundings, but once this information has been mapped into spatial memory, humans can use that information independently of the size of their “window” to the world. However, subjects' spatial memory has some limitations, since the ability to remember precise locations becomes poorer as the amount of information to remember increases. The effects of additional context provided in Experiment 2 resulted in a slight increase in the precision with which subjects could remember specific target locations. The results of these studies have implications in two areas: human spatial cognition, and the design of helmet-mounted displays.