The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 06, 2001
Filed:
Dec. 17, 1999
John W. Smay, Redondo Beach, CA (US);
The Boeing Company, Seattle, WA (US);
Abstract
A method and apparatus for controlling a spacecraft having a first axis is disclosed. The apparatus comprises a momentum wheel unidirectionally rotatable about a spin axis substantially co-aligned with the first axis; a momentum wheel mount for tilting the momentum wheel about at least one of two axes substantially orthogonal to the spin axis; and a processor in communication with the momentum wheel and the momentum wheel mount. The processor commands either the momentum wheel speed or the momentum wheel tilting to control the attitude of the spacecraft in a first orientation and in a second orientation inverted from the first along the first axis, using the same control law. The method comprises the steps of tilting the momentum wheel according to the control law as applied to a spacecraft attitude command and a measured attitude of the spacecraft; angularly displacing the spacecraft from a first orientation to a second orientation substantially inverted from the first orientation, and tilting the momentum wheel according to the same control law applied to the spacecraft altitude command or a new command and the measured attitude of the spacecraft. The article of manufacture comprises a program or data storage device tangibly embodying instructions to perform the method steps described above.