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Marine Electronics


January 2013 Issue

Quasar ROVs Handle Explosive Ordnance Disposal in North Sea
Hallin Marine's (Singapore) contract to locate and remove unexploded World War II bombs from the German sector of the North Sea has been extended to 11 months. The project, begun at the start of 2012, continues similar work carried out in June 2011 and deploys two Quasar 125-horsepower, work-class ROVs.

The Quasar 125 is rated to 3,000 meters and has a 250-kilogram payload. Fully certified for Zone 2 (Class 1 Division 2) hazardous-area operations, it is fitted with a 92-kilowatt hydraulic drive system, a manipulator, video cameras with motorized pan and tilt, and up to six 250-watt lamps, all controllable from the surface.'

The site being cleared is part of the new OWP Riffgat offshore wind farm. The Quasars, with a Teledyne TSS (Watford, England) TSS 440 pulse induction system, allows long-range detection of buried subsea targets. Although designed to sense buried pipelines or cables, the TSS 440 has proved highly effective for locating munitions buried in the seabed. Hallin has also provided a zip jet pump to assist in the retrieval of suspected explosive devices.

The Quasar submersibles have been operating from the Coastal Challenger and Zwerver III shallow-draft support vessels. No unexpected detonations have occurred so far, nor has loss or damage to an ROV.

Algorithms Enable AUVs to Avoid Obstacles Independently
Engineers at Stanford and the Monterey Bay Aquarium Research Institute (MBARI) have developed a system that allows AUVs to better anticipate obstacles in their path. The software system developed by Sarah Houts, a doctoral candidate in Stanford's Aerospace Robotics Laboratory, would for the first time allow vehicles to autonomously image twisting ravines and other hazardous topographical features. Until now, scientists could image these tricky spaces only by remotely steering a vehicle from aboard a ship.

Taking a series of photographs of the same areas over time helps scientists monitor the seabed for change. Noting changes in species and habitats can help, for instance, in measuring climate change.

Houts built on the terrain-relative navigation (TRN) system developed by Stephen Rock, the director of the Aerospace Robotics Laboratory, and MBARI engineer Rob McEwen. TRN allows a vehicle to know its location by matching its altitude to an existing terrain map. But the AUV also needed the ability to anticipate and avoid obstacles, so it applies algorithms to steer itself around obstructions in its path.'

''' The engineers ran a successful field test with the new AUV system in Monterey Bay in November. In a test that was planned for December, they were to compare that flight path to the one the AUV takes using algorithms.

Rock expects his group to begin running missions with the new system by next year. He said that this work is part of a 'tremendous shift' from ROVs to AUVs.

Wave Glider Sets World Record In Pacific Crossing
The first Pacific-crossing (PacX) Wave Glider, Papa Mau, completed in December its 9,000-nautical-mile journey across the Pacific Ocean to set a new world record for the longest distance traveled by an autonomous vehicle.

Papa Mau, built by Wave Glider manufacturer Liquid Robotics (Sunnyvale, California), weathered gale-force storms, fended off sharks, spent more than 365 days at sea, traveled around the Great Barrier Reef and surfed the East Australian Current to reach its final destination in Hervey Bay near Bundaberg, Australia.

The glider measured more than 1,200 miles of a chlorophyll bloom along the Equatorial Pacific. These blooms indicate proliferation of phytoplankton that is fundamental to ocean life and climate regulation. While typically monitored through satellite imagery, direct validation of chlorophyll blooms at this resolution provides a link between scientific modeling and in-situ measurement of the Pacific Ocean.

Liquid Robotics is providing open access to this data as part of its PacX Challenge, a global competition seeking new ocean applications and research using the PacX data. The winner will receive a $50,000 research grant from BP plc (London, England) and six months of Wave Glider data services.

The five PacX finalists are: J. Michael Beman, of the University of California Merced; Nicole Goebel, of the University of California Santa Cruz; Andrew Lucas, of the Scripps Institution of Oceanography; Elise Ralph, of Wise Eddy (Boston, Massachusetts); and Tracy Villareal, of the University of Texas.

AUV With Sensor Suite Maps Oil Spills in Arctic
AUVs are part of the new methods being developed to detect oil spills as oil exploration expands to the Arctic, The Economist reported in December.

Researchers from the Scottish Association for Marine Science conducted tests in 2012 at the Cold Regions Research Engineering Laboratory in New Hampshire by equipping an AUV with a suite of sensors, including multibeam sonar. Under the ice, the AUV fired pulses of sound upwards. Ice and oil reflected the sound waves back, enabling mapping of the presence of oil. The oil layer's thickness was measured to within millimeters. The accuracy and reliability of this method could be improved by combining multiple detection systems, including cameras, sonar and lasers.

While detection and mapping technologies for spilled oil in the Arctic are fast improving, cleanup options remain limited to skimming or burning the oil, or applying chemical dispersants to break it down for digestion by naturally occurring bacteria.

Mini-ROV Inspects Sunken Scallop Boat Off Cape Cod
The U.S. Coast Guard and Massachusetts state police divers used in late November a Teledyne Benthos (North Falmouth, Massachusetts) MiniROVER ROV to inspect the 40-foot fiberglass Twin Lights scallop boat that capsized and sank earlier that month, Cape Cod Times reported. The ROV dove to 198 feet in churning water.

Capt. Jean Frottier, 69, is thought to have gone down with the vessel. A nearby lobster boat rescued the crewman Eric Rego.

The boat was found on the seafloor 2 miles north of Race Point, Massachusetts, using a side scan sonar.


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