Investigation of Motion Requirements in Compensatory Control Tasks

Tests consisting of one- and two-axis closed-loop tracking tasks, with and without motion, have been made to define some areas where motion cues are beneficial. Tests were made with reduced scaling on the motion input to investigate the minimum requirements of motion cues in those tests where motion was found to be of assistance. For the set of conditions tested, little or no difference in the measurement criteria was observed in the single-axis motion/no motion runs. Similar results were obtained when comparing two single-axis tests with different pitch orientation. The two-axis tests, which consisted of pitch and yaw and pitch and roll, did, however, produce a difference in the error measurements in the motion/no motion comparison. A decrease in normalized tracking error and an increase in closed-loop system frequency were observed when motion was added. Tests were also run, in pitch and yaw only, in which the scale of the motion input was reduced. These tests were performed by the subject in sequence starting with no motion all the way to full motion and back down to no motion. Each motion scale condition (none, 1/16, ⅛, ¼, ½, and full) constituted a test. The normalized tracking error remained constant for full, ½, and ¼ motion scaling, but increased with a further reduction in motion scaling.