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:
May. 02, 1995
Filed:
Dec. 23, 1992
Sibnath Basuthakur, Rancho Palos Verdes, CA (US);
Bernard Soriano, Los Angeles, CA (US);
Hughes Aircraft Company, Los Angeles, CA (US);
Abstract
The estimation and compensation of fixed, but unknown uncertainties of a thruster (22) for improving satellite attitude estimation and control as well as eliminating the need for nutation damping devices is disclosed. A thruster (22) is fired and an attitude state is estimated using an estimator (116). A commanded rate change (122) is calculated, which is modified using a compensating feedforward command (126) as updated by a fixed uncertainty estimator (124) unless an estimated rate is less than an absolute value of a threshold rate. The modified commanded rate change (130) is used to incrementally adjust thruster fire on-time (104) until a predetermined satellite trajectory is reached.