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An Analytical Evaluation of Unmanned Aircraft System Warning Signals as Processed by a Model of Color Vision Deficiencies

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Technical Report

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U.S. Army Aeromedical Research Laboratory Fort Rucker United States

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In order to assist in the determination of the need for U.S. Army color vision requirements for unmanned aircraft system UAS operators, representative cockpit display images from the Shadow and Gray Eagle Universal Mission Simulator UMS were collected and analyzed. The UMS monitors, graphics engines, display characteristics, and especially cautionwarning imagery are identical to those used in Shadow and Gray Eagle tactical cockpits. Of particular interest were warning or cautionary signals consisting of text overlaid over colored backgrounds. Three background colors were used in order of priority red for warning, bronze for caution, and blue for advisory. Color vision deficiency CVD matrix coefficients for protanomalous, deuteranomalous, and tritanomalous observers with CVD severity indices of 0 to 1.0 normal to dichromat, were applied to the RGB values for each of the three alert background colors. Twenty-one swatches representing 21 severity scores were created for the three color deficiencies. Swatch RGB colors were converted to CIELAB color space in order to calculate distances between swatches which have previously been used to correlate with perceptual color confusion metrics. Using a CIELAB criterion separation distance of thirteen, only the red-yellow swatch distances for the more severe deuteranomalous observer fell below the criterion.

Subject Categories:

  • Pilotless Aircraft
  • Flight Control and Instrumentation

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