Attitude control methods and systems for multiple-payload spacecraft

DETAILED DESCRIPTION The present invention is directed to attitude control methods and systems for multiple-payload spacecraft.
The invention recognizes that payload attitudes must be determined to reduce relative attitude errors between payloads.
The invention thus provides an integrated attitude determination architecture that combines attitude measurements from all payloads to determine a master attitude estimate for a master payload and relative slave attitude estimates for the remaining slave payloads.
These estimates are then used to control the attitudes of spacecraft elements that correct the absolute and relative attitude errors.
It has been found that systems of the invention significantly enhance the accuracy of the attitude estimates when compared to systems that realize independent payload estimates, determine payload attitudes.
In addition, it has been found that estimating relative slave attitudes provides significant processing advantages (e.
g.
, simpler algorithms, reduced data throughput and slower processing rate) when compared to other methods.
The novel features of the invention are set forth with particularity in the appended claims.
The invention will be best understood from the following description when read in conjunction with the accompanying drawings.