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Evaluating Spacecraft Attitude

IP.com Disclosure Number: IPCOM000091694D
Original Publication Date: 1968-Apr-01
Included in the Prior Art Database: 2005-Mar-05
Document File: 2 page(s) / 58K

Publishing Venue

IBM

Related People

Bombard, RF: AUTHOR [+3]

Abstract

The system evaluates the attitude of a spacecraft with respect to its on-board inertial reference system. The attitude of spacecraft A is determined by a precision reference system carried on board. Such system utilizes a pair of gimballed daylight star trackers 10 and 11 which track reference stars B and C. An on-board computer samples the information from trackers 10 and 11 and computes the attitude of the spacecraft with respect to the on-board reference system established by stars B and C.

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Evaluating Spacecraft Attitude

The system evaluates the attitude of a spacecraft with respect to its on- board inertial reference system. The attitude of spacecraft A is determined by a precision reference system carried on board. Such system utilizes a pair of gimballed daylight star trackers 10 and 11 which track reference stars B and C. An on-board computer samples the information from trackers 10 and 11 and computes the attitude of the spacecraft with respect to the on-board reference system established by stars B and C.

In order to evaluate the on-board inertial reference system, there is provided at a known ground site a pair of gimballed daylight star trackers 12 and 13, each of which tracks one of the stars B and C. The information from trackers 12 and 13 is fed to a ground computer. This calculates the inertial reference system of the ground station with respect to stars B and C. Provided at the ground station is a bore-sighted laser transmitter and receiver, the laser beam of which tracks spacecraft A. For this purpose, a retro-reflector array is provided on spacecraft A and the transmitted laser beam is reflected from its surface back into the laser receiver. Also carried on spacecraft A is optical pointing device OPD which is used to track the ground station in its field of view FOV.

Information from the pointing angle of the tracking laser beam line of sight is correlated with the ground inertial reference system and transmitted to sending station D....