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Abstract
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A research program is underway whose goal is to provide engineering guidelines on target image sufficiency for training tactics and maneuvering skills in ground based flight simulators. A preliminary experiment was carried out in the Naval Training Equipment Center's Visual Technology Research Simulator (VTRS), using computer-generated aircraft images displayed on a dome via a variable-resolution target projector. The experiment examined aspect recognition sensitivity, or the distance at which subjects could determine the orientation of another aircraft.
For our initial effort, the aspect (orientation) recognition task was simplified in the following ways: a) on each trial one of only 16 stationary target orientations of a TA4J aircraft was presented, b) targets had the same length/width ratio; c) subjects made binary up/down judgments; d) a staircase method provided thresholds for aspect recognition range. Four different target luminances, and three background luminances were combined with four different levels of projector resolution in a partial parametric study to assess the relative effects of contrast, resolution and brightness.
All main effects were found to be significant. Over the ranges studied, contrast accounted for the most variance and brightness the least. In the best condition studied, aspect recognition was performed successfully at >4 miles (a 5.5 arc minute target), whereas the most degraded condition showed thresholds at 1.5 miles (a 14 arc minute target). These are comparable to distances known to be required in outdoor training ranges and in combat. An additional finding is that reliable subject differences were substantial (>20% of the total accounted for variance). The four subjects who were tested in this study had normal or better vision by static and dynamic tests of contrast sensitivity. Individual differences in these subjects' contrast sensitivity scores were predictive of their visual performance on this target aspect recognition task. These data are discussed from the standpoint of the utility of this paradigm for providing guidelines for training equipment design.
Language: en |