Project “Mobile Underwater Vector Gravity Sensor” (MoVeGra)
The objective of MoVeGra is to mature the technology of a novel type of vector gravity sensor to be used on Autonomous Underwater Vehicles (AUV). This proposal is the follow-up of a larger project, GRAVIMOB, which developed and built the first prototype and tested it during a cruise (GRAVIMOB 2016, funded by the French Oceanographic Fleet-FOF).
the objectives of ANR research axis 01 as this new sensor will allow:
- improving the knowledge of the crustal structure (porosity, alteration) and fluid circulation associated with hydrothermal vents, which impact the fluxes of diverse elements, and,
- evaluating the economic potential of the mineral deposits associated with these environments.
The concept of GRAVIMOB is based on direct measurements of accelerations along three axes (De Saint Jean, 2008). The system is composed of six accelerometers mounted in two co-linear triads, integrated on a glass sphere, which also holds the data loggers and additional sensors (Figure 1). It is therefore a vector gravity meter allowing, after data processing, to determine the three components of the gravity acceleration.
GRAVIMOB sensor (left), sphere in a frame for AUV AsterX (centre), AUV AsterX (right) AUV AsterX @IFREMER
Main partners: LGO ESGT (Le Mans)
Collaborations: IGN, SHOM, IFREMER
Prototype built by MAPPEM Geophysics, funded by CPER Bretagne
Test cuise GRAVIMOB (NO Europe, AUV AsterX), May 2016, funded by FOF, Labex MER, LGO
Test cruise GRAVIMOB-2 (NO Europa, AUV) evaluated A+ by the French Coastal Fleet Committee (CNFC)
Bibliography
Roussel, C., J. Verdun, J. Cali, M. Maia, and J. F. d’EU. “Integration of a strapdown gravimeter in an autonomous vehicle.” ISPRS – International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XL– 5/W5 (April 9, 2015) : 199–206. doi :10.5194/isprsarchives-XL-5-W5-199-2015
Thèse (DGA): Roussel, C. Expérimentation d’un gravimètre mobile léger et novateur pour la mesure du champ de gravité en fond de mer, 2017 (https://tel.archives-ouvertes.fr/tel-01635884)
