P. Santos, pjsantos(at)ualg.pt
P. Felisberto, pfelis(at)ualg.pt
F. Zabel fredz(at)wireless.com.pt,
S.M. Jesus sjesus(at)ualg.pt
LarSys, Universidade do Algarve, Campus de Gambelas, PT-8005-139 Faro, Portugal.
and
L. Sebastião l.sebastiao(at)isr.tecnico.ulisboa.pt,
LarSys, IST, Universidade de Lisboa, 1005 Lisboa (Portugal).
.
Comments: download pdf (not available).
Ref.: 173rd Meeting of the ASA, Boston, MA, USA, June
2017.
Abstract
n seismic geo-acoustic exploration, the use of ships equipped with long streamers is of major concern
due to the complexity of the operations. The European project WIMUST aims to improve the efficacy of
actual geo-acoustic surveys through the use of AUVs towing short streamers. A Dual Accelerometer Vector
Sensor (DAVS) was developed in order to complement the streamer’s data, allowing for the reduction of
their size and facilitating the operation of the WiMUST distributed configuration. Each DAVS consists
of two tri-axial accelerometers and one hydrophone aligned along a vertical axis. This configuration
has the ability to cancel or significantly attenuate the direct and the surface reflection paths, which
are undesirable in seismic imaging. Calibration tests with the DAVS have already been performed; this
paper presents experimental results on the estimation of azimuthal directions when the DAVS is in motion.
Signals in the 1-2kHz band were emitted by a source deployed in a shallow pond at 1.5m depth and acquired
by the DAVS mounted on a MEDUSA class AUV, which was following a pre-programed path with a 0.26m/s nominal
speed. The azimuth estimates are coherent with the MEDUSA trajectories even in curved paths where the
thruster noise increases.
ACKNOWLEDGMENT: This work was funded under project WiMUST contract 645141, H2020 program of the EU.