Variable Rate Control Research Articles

Control of a remote maneuvering unit during satellite inspection.

Operator performance in flying a simulated remote maneuvering unit (RMU) on a coplanar satellite in-pection mission was evaluated under two conditions of RMU attitude control and two condiitons of cockpit instrumentation. The maneuver was repeatedly performed successfully using either an on-off acceleration-command attitude control system or an on-off rate-command attitude control system, each with either a full panel of cockpit instruments (six) or only one cockpit instrument. The rate-command system was found to be superior for pitch control during station keeping and for roll control in general. The acceleration-command system was superior for pitch control during the trajectory portions of the mission. Because both control systems had disadvantages, investigation of a variable rate-control system is recommended. More economical and precise RMU control was obtained under the full-panel cockpit instrumentation condition irrespective of the control system used. The instruments of most value were found to be those which provided X (longitudinal) and Z (vertical) distance information. The limitations of the simulation and the advantages and disadvantages of an “inside-out“ versus an “outside-in“ television display of the target and its surrounds are also discussed.