A performance-based evaluation of B-2 cursor system gain functions for use on navigational update and targeting tasks

Sixteen USAF crew members participated in experiments evaluating cursor slewing performance with the B-2 radar-embedded cursor system. Performance was evaluated with the current linear force/velocity function and an alternative sigmoidal function designed to elicit improved performance. One experiment utilized a radar update task requiring only fine positioning movements of the cursor. The second experiment consisted of a semi-operational targeting task in which both gross and fine positioning movements of the cursor were required. In addition, the effects of ambiguity of the target pixel and variability in cursor system processing delay were examined. In both experiments, the sigmoidal gain function elicited lower designation time and fewer overshoots than the linear function. Although accuracy of the final designation was not affected by gain function in either experiment, designation error was found to be less than one pixel when the target pixel was highlighted. Variability in the length of the cursor processing delay did not significantly impact designation error, designation time, or the number of overshoots. Subjectively, crew members unanimously preferred the sigmoidal function for performing aimpoint designation.