MICROSCOPE instrument description and validation

Françoise Liorzou; Pierre Touboul; Manuel Rodrigues; Gilles Métris; Yves André; Joel Bergé; Damien Boulanger; Stefanie Bremer; Ratana Chhun; Bruno Christophe; Pascale Danto; Bernard Foulon; Daniel Hagedorn; Emilie Hardy; Phuong-Anh Huynh; Claus Lämmerzahl; Vincent Lebat; Meike List; Frank Löffler; Benny Rievers; Alain Robert; Hanns Selig

arXiv · 2012.11232

MICROSCOPE instrument description and validation

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Abstract

Dedicated accelerometers have been developed for the MICROSCOPE mission taking into account the specific range of acceleration to be measured on board the satellite. Considering one micro-g and even less as the full range of the instrument, leads to a customized concept and a high performance electronics for the sensing and servo-actuations of the accelerometer test-masses. In addition to a very accurate geometrical sensor core, a high performance electronics architecture provides the measurement of the weak electrostatic forces and torques applied to the test-masses. A set of capacitive sensors delivers the position and the attitude of the test-mass with respect to a very steady gold coated cage made in silica. The voltages applied on the electrodes surrounding each test-mass are finely controlled to generate the adequate electrical field and so the electrostatic pressures on the test-mass. This field maintains the test-mass motionless with respect to the instrument structure. Digital control laws are implemented in order to enable instrument operation flexibility and a weak position sensor noise. These electronics provide both the scientific data for MICROSCOPE's test of General Relativity and the data for the satellite drag-free and attitude control system (DFACS).

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Françoise Liorzou, Pierre Touboul, Manuel Rodrigues, Gilles Métris, Yves André, Joel Bergé, Damien Boulanger, Stefanie Bremer, Ratana Chhun, Bruno Christophe, Pascale Danto, Bernard Foulon, Daniel Hagedorn, Emilie Hardy, Phuong-Anh Huynh, Claus Lämmerzahl, Vincent Lebat, Meike List, Frank Löffler, Benny Rievers, Alain Robert, Hanns Selig. 2020-12-21. MICROSCOPE instrument description and validation. https://arxiv.org/abs/2012.11232

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