Effects of cue saliency in an assisted target detection system for search and rescue

Assisted target detection (ATD) systems are designed to support operators in complex visual search tasks by determining areas within the visual scene that have a higher probability of containing a target. These locations must somehow be conveyed to the operators via a human-machine interface, and little work has been done on the design of the cues themselves. The type of visual cue may affect search performance and visual scan paths, and if operators find that an ATD system disrupts their performance of the task they will not use the system. In order to investigate the effects of cue saliency on operator performance, a circular translucent cue with two levels of brightness was tested in a simulated search and rescue task. Despite the use of cues that had a relatively low reliability, both types of cues resulted in improved detection performance. There was an effect of cue brightness such that brighter cues were most advantageous when there were fewer cues in the scene. Varying characteristics of the visual cues were observed to have an impact on how the operator scans the scene.