An automatic control scheme for spacecraft proximity operations is presented. The controller is capable of holding the vehicle at a prescribed location relative to a target, or maneuvering it to a different relative position using straight line-of-sight translations. The autopilot uses a feedforward loop to initiate and terminate maneuvers, and for operations at nonequilibrium set-points. A multivariate feedback loop facilitates precise position and velocity control in the presence of sensor noise. The feedback loop is formulated using the Linear Quadratic Gaussian (LQG) with Loop Transfer Recovery (LTR) design procedure. Linear models of spacecraft dynamics, adapted from Clohessey-Wiltshire Equations, are augmented and loop shaping techniques are applied to design a target feedback loop. The loop transfer recovery procedure is used to recover the frequency domain properties of the target feedback loop. The resulting compensator is integrated into an autopilot which is tested in a high fidelity Space Shuttle Simulator. The autopilot performance is evaluated for a variety of proximity operations tasks envisioned for future Shuttle flights.
Linear Quadratic Gaussian with Loop Transfer Recovery Proximity Operations Autopilot for Spacecraft
1987
180 pages
Report
No indication
English
Unmanned Spacecraft , Manned Spacecraft , Automatic pilots , Spacecraft control , Stationkeeping , Feedforward control , Flight operations , Linear quadratic gaussian control , Flight simulation , Fuel consumption , Linear equations , Positioning , Space shuttles , Spacecraft maneuvers , Velocity , Translations
British Library Conference Proceedings | 2006
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