Patent Number: 6,298,288

Title: Autonomous gyro scale factor and misalignment calibration

Abstract: A system and method of estimating the attitude of a spacecraft is disclosed. A three-axis inertial-based estimate of spacecraft attitude is produced and is compared to a stellar-based estimate of spacecraft attitude. A Kalman filter having states associated with gyro scale factor and/or misalignment errors compares the stellar-based attitude estimate to the inertial-based estimate of attitude and apportions the total error into three time varying matrices. A first time varying matrix is associated with gyro scale factor and misalignment errors, a second time varying matrix is associated with gyro bias errors, and a third time varying matrix is associated with attitude errors. The time varying matrices are applied as corrective feedbacks to the inertial-based estimate of spacecraft attitude and are adaptively adjusted to minimize the error therein.

Inventors: Li; Rongsheng (Hacienda Heights, CA), Wu; Yeong-Wei A. (Rancho Palos Verdes, CA), Didinsky; Garry (Niles, IL)

Assignee: Hughes Electronics Corp.

International Classification: B64G 1/36 (20060101); B64G 1/28 (20060101); B64G 1/24 (20060101); G05D 1/08 (20060101); G06F 007/70 (); B64G 001/24 ()

Expiration Date: 10/02/2018