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:
Sep. 22, 1998
Filed:
Jul. 10, 1996
Bernard M Anzel, El Segundo, CA (US);
Hughes Electronics Corporation, El Segundo, CA (US);
Abstract
A method and apparatus for satellite station keeping is disclosed in which six thrusters are mounted on the anti-nadir face of a satellite with their direction of thrust passing through the center of mass (CM) of the satellite. The thrust lines of the north trio of thrusters and the south trio of thrusters make an angle .theta. with the satellite north-south axis in a northern and southern direction, respectively. The four outer thrusters are laterally separated and slewed by an angle .alpha. about the north-south axis. Each outer thruster produces three components of .DELTA.V, i.e. normal, tangential and radial (toward the Earth), thereby providing complete control of the three orbit vectors, inclination, eccentricity and mean motion. The north and south center thrusters are positioned in the Local-Vertical North-South plane and produce only normal and radial .DELTA.V components, providing control for momentum dumping and, in the event of failure, inclination control. In the event of a thruster failure where one of the pairs of thrusters is shut down, four thrusters remain to maintain station keeping.