NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Method for spinning up a three-axis controlled spacecraftA three-axis controlled spacecraft (1), typically a satellite, is spun up about its roll axis (20) prior to firing a motor (2), i.e., a perigee kick motor, to achieve the requisite degree of angular momentum stiffness. Thrusters (21) for imparting rotation about the roll axis (20) are activated in open-loop fashion, typically at less than full duty cycle. Cross-axis torques induced by this rotational motion are compensated for by means of closed control loops for each of the pitch and yaw axes (30, 40, respectively). Each closed control loop combines a prebias torque (72) with torques (75, 74) representative of position and rate feedback information, respectively. A deadband (52) within each closed control loop can be widened during the spinup, to conserve fuel. Position feedback information (75) in each of the control loops is disabled upon saturation of the gyroscope associated with the roll axis (20).
Document ID
20080004093
Acquisition Source
Goddard Space Flight Center
Document Type
Other - Patent
Authors
Vorlicek, Preston L.
Date Acquired
August 24, 2013
Publication Date
February 16, 1988
Subject Category
Spacecraft Design, Testing And Performance
Report/Patent Number
Patent Number: US-PATENT-4,725,024
Patent Application Number: US-PATENT-APPL-SN-798271
Funding Number(s)
CONTRACT_GRANT: NAS5-29500
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
Patent
US-PATENT-4,725,024
Patent Application
US-PATENT-APPL-SN-798271
No Preview Available