Human Operator Dynamics for Aural Compensatory Tracking

The effects of aural and combined aural and visual displays of tracking error on human operator dynamics were investigated using a compensatory tracking task. The aural displays indicated error magnitude with tone pitch and error polarity by either modulating the tone or by switching it between the ears. Describing functions, remnants, and rms tracking performance were measured with test conditions which were similar to those for previous studies of visual tracking performance. Human operator control characteristics measured for aural displays agree closely with those which result for visual displays. Also, operators could control equally well with either one- or two-ear displays. However, the reduction in operator time delays, expected because of the generally faster human response to aural stimuli, was not clearly evident in the results. Results also indicate that the combined aural and visual presentation of tracking error improved operator performance slightly.