Magnetic torquer induced disturbing signals within GRACE accelerometer data

Research output: Contribution to journalArticleResearchpeer review

Authors

  • Nadja Peterseim
  • Jakob Flury
  • Anja Schlicht

Research Organisations

External Research Organisations

  • Technical University of Munich (TUM)
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Details

Original languageEnglish
Pages (from-to)1388-1394
Number of pages7
JournalAdvances in space research
Volume49
Issue number9
Early online date22 Feb 2012
Publication statusPublished - 1 May 2012

Abstract

The GRACE (Gravity Recovery And Climate Experiment) gravity field satellite mission was launched in 2002. Although many investigations have been carried out, not all disturbances and perturbations upon satellite instruments and sensors are resolved yet. In this work the issue of acceleration disturbances onboard of GRACE due to magnetic torquers is investigated and discussed. Each of the GRACE satellites is equipped with a three-axes capacitive accelerometer to measure non-gravitational forces acting on the spacecraft. We used 10 Hz Level 1a raw accelerometer data in order to determine the impact of electric current changes on the accelerometer. After reducing signals which are induced by highly dominating processes in the low frequency range, such as thermospheric drag and solar radiation pressure, which can easily be done by applying a high-pass filter, disturbing signals from onboard instruments such as thruster firing events or heater switch events need to be removed from the previously filtered data. Afterwards the spikes which are induced by the torquers can be very well observed. Spikes vary in amplitude with respect to an increasing or decreasing current used for magnetic torquers, and can be as large as 20 nm/s 2 . Furthermore, we were able to set up a model for the spikes of each scenario with which we were able to compute model spike time series. With these time series the spikes can successfully be removed from the 10 Hz raw accelerometer data. Spectral analysis of the time series reveal that an influence onto gravity field determination due to these effects is very unlikely, but can theoretically not be excluded.

Keywords

    Accelerometer, GRACE, Magnetic Torquers

ASJC Scopus subject areas

Cite this

Magnetic torquer induced disturbing signals within GRACE accelerometer data. / Peterseim, Nadja; Flury, Jakob; Schlicht, Anja.
In: Advances in space research, Vol. 49, No. 9, 01.05.2012, p. 1388-1394.

Research output: Contribution to journalArticleResearchpeer review

Peterseim N, Flury J, Schlicht A. Magnetic torquer induced disturbing signals within GRACE accelerometer data. Advances in space research. 2012 May 1;49(9):1388-1394. Epub 2012 Feb 22. doi: 10.1016/j.asr.2012.02.013
Peterseim, Nadja ; Flury, Jakob ; Schlicht, Anja. / Magnetic torquer induced disturbing signals within GRACE accelerometer data. In: Advances in space research. 2012 ; Vol. 49, No. 9. pp. 1388-1394.
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abstract = " The GRACE (Gravity Recovery And Climate Experiment) gravity field satellite mission was launched in 2002. Although many investigations have been carried out, not all disturbances and perturbations upon satellite instruments and sensors are resolved yet. In this work the issue of acceleration disturbances onboard of GRACE due to magnetic torquers is investigated and discussed. Each of the GRACE satellites is equipped with a three-axes capacitive accelerometer to measure non-gravitational forces acting on the spacecraft. We used 10 Hz Level 1a raw accelerometer data in order to determine the impact of electric current changes on the accelerometer. After reducing signals which are induced by highly dominating processes in the low frequency range, such as thermospheric drag and solar radiation pressure, which can easily be done by applying a high-pass filter, disturbing signals from onboard instruments such as thruster firing events or heater switch events need to be removed from the previously filtered data. Afterwards the spikes which are induced by the torquers can be very well observed. Spikes vary in amplitude with respect to an increasing or decreasing current used for magnetic torquers, and can be as large as 20 nm/s 2 . Furthermore, we were able to set up a model for the spikes of each scenario with which we were able to compute model spike time series. With these time series the spikes can successfully be removed from the 10 Hz raw accelerometer data. Spectral analysis of the time series reveal that an influence onto gravity field determination due to these effects is very unlikely, but can theoretically not be excluded.",
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Download

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AU - Flury, Jakob

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