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Integration of TLS and sonar for the modelling of semi-immersed structures
Published in Belén Riveiro, Roderik Lindenbergh, Laser Scanning, 2019
Emmanuel Moisan, Philippe Foucher, Pierre Charbonnier, Samuel Guillemin, Mathieu Koehl, Pierre Grussenmeyer
In this chapter, the focus is on building 3D models as accurate as possible. For the aerial part, out of water, it is classic to use laser scanning in a static acquisition framework, which makes it possible to reach accuracies better than the centimetre. Today, there are recent sonar technologies which, thanks to a mechanical scanning system, allow the use of multibeam echosounders with an implementation close to that of static laser scanners, even if the precision obtained in comparison with the laser is less (Lesnikowski and Rush, 2012; Moisan et al., 2016). The method described in this chapter, whose scope extends beyond canal tunnels alone, mixes mechanical scanning sonar (MSS; Lesnikowski and Rush, 2012) and terrestrial laser scanner (TLS; Grussenmeyer et al., 2016) technologies to construct a reference model of the infrastructure. This one, directly usable by the manager for the documentation or the inspection of the infrastructure, can also serve to evaluate the results obtained by other surveying methods, in particular mobile mapping systems.
Shallow marine sediments characterisation of the Bagnoli brownfield site, Pozzuoli Bay (Italy)
Published in Chemistry and Ecology, 2020
M. Vallefuoco, S. Tamburrino, M. Sacchi, A. Guarino, G. Di Martino, R. Tonielli, M. Sprovieri, S. Passaro
Bathymetric data were collected by using a Teledyne Reson SeaBat 7125 multibeam echosounder, a multi-frequencies multibeam (200–400 kHz) that provides measurements until a maximum depth of data of 450 m. The equipment is characterised by 512 beam receivers and the equipment is completed by a real-time interfacing with DGPS (Trimble BX982) for positioning and by an SBG EkinoxU inertial system for dynamic motion compensation (heave, pitch, roll, yow and velocity).
Modelling of the reef benthic habitat distribution within the Cabrera National Park (Western Mediterranean Sea)
Published in Annals of GIS, 2021
Dulce Mata, Jose Úbeda, Adrián Fernández-Sánchez
During the geophysical survey, the team was working simultaneously with a multibeam echosounder (MBE) model EM3002D, a high resolution system at 300 kHz frequency (Kongsberg 2006) and a Topographic Parametric Sonar PS040. The navigation was in parallel lines, maintaining an equidistance of 150 meters and following IHO standards. This distance generated 25% overlapped areas between records.