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Sweet, Barbara

Publications and source records attributed to Sweet, Barbara.

Effects of Spatio-Temporal Aliasing on Pilot Performance in Active Control Tasks

Spatio-temporal aliasing affects pilot performance and control behavior. For increasing refresh rates: 1) Significant change in control behavior: a) Increase in visual gain and neuromuscular frequency. b) Decrease in visual time delay. 2) Increase in tracking performance: a) Decrease in RMSe. b) Increase in crossover frequency.

Zaal, Peter

Visual Cueing Effects Investigation for a Hovering Task

In simulators, as in actual aircraft, pilots conduct their missions according to perceived vehicle performance and spatial orientation from out-the-window (OTW) information. Ground-based flight simulations rely upon computer-generated OTW visual scenes. The realism and fidelity of a specific OTW simulation therefore has a significant impact on mission effectiveness. This study investigates effects of three visual parameters of the computer-generated image system (field-of-view, collimation, and resolution) on a disturbance-rejection hovering task. Pilots' performance and workload were studied under the following conditions: collimated optics vs. noncollimated optics, wide field-of-view (FOV) vs. narrow FOV, and higher resolution vs. lower resolution. Subjects were instructed to maintain a station-keeping position during disturbances while piloting an uncoupled four degrees-of-freedom (DOF) helicopter model, which had a satisfactory rate-command system in pitch and roll axes and ideal heading and altitude hold. Display collimation and FOV were found to have significant effects on pilots performance and subjective their subjective perception of visual cueing quality.

Chung, William W. Y.