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Toward Accurate On-Ground Attitude Determination for the Gaia Spacecraft


The work presented in this paper concerns the accurate On-Ground Attitude (OGA) reconstruction for the astrometry spacecraft Gaia in the presence of disturbance and of control torques acting on the spacecraft. The reconstruction of the expected environmental torques which influence the spacecraft dynamics will be also investigated.

The telemetry data from the spacecraft will include the on-board real-time attitude, which is of order of several arcsec. This raw attitude is the starting point for the further attitude reconstruction. The OGA will use the inputs from the field coordinates of known stars (attitude stars) and also the field coordinate differences of objects on the Sky Mapper (SM) and Astrometric Field (AF) payload instruments to improve this raw attitude. The on-board attitude determination uses a Kalman Filter (KF) to minimize the attitude errors and produce a more accurate attitude estimation than the pure star tracker measurement. Therefore the first approach for the OGA will be an adapted version of KF. Furthermore, we will design a batch least squares algorithm to investigate how to obtain a more accurate OGA estimation. Finally, a comparison between these different attitude determination techniques in terms of accuracy, robustness, speed and memory required will be evaluated in order to choose the best attitude algorithm for the OGA. The expected resulting accuracy for the OGA determination will be on the order of milli-arcsec.

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  1. C. de Boor, A Practical Guide to Splines, 1st edn. (Springer, New York, 1978)

  2. O. Montenbruck, E. Gill, Satellite Orbits—Models, Methods, and Applications, 1st edn. (Springer, Berlin, 2000)

  3. J.L. Crassidis, J.L. Junkins, Optimal Estimation of Dynamic Systems, 1st edn. (Chapman and Hall/CRC, New York, 2004)

  4. EADS, A., ESA Document, Feb. 2007

  5. L., L. ESA Document, July 2000

  6. L., L. ESA Document, March 2001

  7. F. Safa, ESA Document, 15 March 2006

  8. M.A. Samaan, S. Theil, AAS/AIAA Space Flight Mechanics Meeting, Sendona, AZ, Paper 07, Jan. 2007

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Author information

Correspondence to Malak A. Samaan.

Additional information

Satellite Dynamics, Modelling, In-Orbit Calibration and Data Processing Workshop, Bremen, Germany, 21–23 May 2008.

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Samaan, M.A. Toward Accurate On-Ground Attitude Determination for the Gaia Spacecraft. Space Sci Rev 151, 227–241 (2010). https://doi.org/10.1007/s11214-009-9588-4

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  • Satellite dynamics