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NORBIT velocity 2014 For more Solutions visit 16 opment of their all-new curved-array multibeam sonar system." since 1998, he says, seahorse has been in- volved in the marine surveying sector, provid- ing seismic surveying, offshore positioning, dredging, coastal engineering, geological sci- ences, acoustic sensor manufacturing and services in hydrographic disciplines. "This put us in a good position to help NorbiT sonar developers to better understand the challeng- es associated with bathymetric mapping and therefore direct r&D efforts towards solv- ing or simplifying these from the ground-up," Mutschler says. "The resulting NorbiT iWbMsc is a tightly integrated, wide-swath multibeam sonar kit with co-located attitude and coupled GNss/ iNs solutions in a small form factor. The critical requirement to meet or exceed strict specifica- tions, as published by the international Hydro- graphic organization, Us Army Corps of Engi- neers, rijkswaterstaat, etc., is maintained." seahorse Geomatics and NorbiT are linked, Mutschler says, "in a boundary-free synergistic working relationship that combines discrete passions for acoustics pioneering and increasing bathymetric mapping efficiencies." The result is the most compact high-perfor- mance sonar available, a revolutionary bottom- mapping solution capable of delivering water- data products of the highest quality. in addition to providing key technical input, says Eriksen, "Mike is our go-to-market partner. He does our system testing and client contact. He represents our products at trade shows and per- forms demonstrations." A truly groundbreaking system Mutschler says the NorbiT iWbMsc system is broadband-enabled, allowing up to 80 kHz FM pulses centered at 400 kHz, and incor- porates a curved receiver array of multiple pi- ezoceramic elements. "This allows for narrow beams to be maintained across a wider angular swath width than typical planar/flat receiver arrays." This results in smaller beam footprints on the bottom surface for increased data reso- lution and accuracy. Multibeam sonar systems are most often mounted on floating or submerged survey vessels that are heading, pitching, rolling, heaving in dif- ferent directions, with varying dynamics at play on or under water surfaces. The NorbiT mul- tibeam sonar measures several hundred beams, each having a unique two-way travel time and across-track pointing angle from nadir which must be combined with accurate survey platform positioning, attitude—roll, pitch and heading— and sound speed to derive a final and repeatable XYZ location on a common projection. "When the different sensors are separated, ver- tical and horizontal uncertainties are increased due to offset measurement errors, sensor mis- alignments and platform flexing," Mutschler explains. To solve this, Norbit puts the NovAtel GNss+iNs deep within the sonar hardware. "The sTiM300 iMU is situated directly inside the already compact sonar head," says Mutschler. "The benefits include fixed and very small lever arm offsets which effectively eliminate sensor-to-sensor flexing, simple setup and integration with a single LAN cable for complete data acquisition on a laptop, and a compact size for simple mounting on nearly any sized platform, from a sea kayak to a large survey ship." NovAtel's ryan Dixon states: "The big deal here is that we are getting a level of correction in rela- tion to price not available in the past. because of the integration there is less possibility of error." Applications abound Mutschler describes a key application for the new system: "in the case of safety of navigation, ves- sel captains and pilots regularly assess the risk level of entering a port utilizing charted informa- tion that includes hydrographic data on bottom depths and material type." They may decide, he explains, to allow the keel to be plowed some 30- 90 cm through a sandy or muddy bottom and " " Norbit puts NovAtel GNSS+iNS deep within the sonar hardware.

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