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:
Apr. 30, 2002
Filed:
Jul. 10, 2000
John S. Higham, Mountain View, CA (US);
Lee Rotlisberger, Fremont, CA (US);
Space Systems/Loral, Inc., Palo Alto, CA (US);
Abstract
A control system and method that keeps solar arrays on a satellite pointing toward the sun. Exemplary control systems and methods are implemented as follows. An orbit propagator computes satellite orbital location data and computes a sun vector referenced to an inertial reference frame. A coordinate transformation processor processes the sun vector in the inertial reference frame and a sensed satellite attitude signal to generate a sun vector referenced to a satellite body reference frame. A solar array position processor processes a step count derived from a solar array pointing control system and sensed solar array position to generate an estimate of the position of the solar array. A summing device sums the solar array position estimate output, the body frame gun vector, and a bias signal derived from a ground command, to produce a solar array position error signal. A filter filters the solar array position error signal. A current regulator processor processes a measured solar array current to produce another solar array position error signal based on current output. An eclipse processor processes the satellite orbital location data, the solar array position error output signal, and the low pass filtered solar array position error signal to generate a step command. The solar array pointing control system processes the step command to generate control signals that point the solar array at the sun.