New models of unmanned underwater vehicles are set for testing this year

Scientists at Nekton Research in Durham, N.C., say their new family of tiny unmanned underwater vehicles has the potential to dramatically reduce the cost of acquiring underwater sensor data

by J.R. Wilson

DURHAM, N.C. — Scientists at Nekton Research in Durham, N.C., say their new family of tiny unmanned underwater vehicles has the potential to dramatically reduce the cost of acquiring underwater sensor data while speeding underwater searches.

Developing these so-called micro autonomous underwater vehicles (microAUVs), which are no larger than bathtub toys, began with the MicroHunter, a low-cost platform for single- or multiple-unit environmental sensing missions. Nekton engineers developed Microhunter in cooperation with Duke University in Durham, N.C., with funding from the Defense Advanced Research Projects Agency (DARPA) in Arlington, Va.

Still in development, MicroHunter prototypes are about eight to 14 inches long and have only one moving part. The tiny MicroHunter will only be suitable for a limited number of specific missions, but provides the basis for a larger microUAV — the Ranger — that will be the workhorse of the breed, says Chuck Pell, Nekton science and technology director.

"MicroHunters are one class of small microvehicle using a rather unique system for guidance that essentially copies the mechanism that certain micro-organisms use to orient themselves," Pell says. "We extracted the algorithm and rendered it as a physical system, so essentially it is a robot cell."

Potential applications for MicroHunter include:

  • verifying satellite data on near-surface sea targets;
  • general operational oceanography in support of military, survey, and other activities; — detecting and tracking acoustic beacons on downed aircraft, divers, or shipping containers;
  • detecting explosives and bio- and chemical-warfare agents;
  • information retrieval from remote or denied areas and underwater harbor patrol;
  • biological and physical oceanographic research; and
  • water quality monitoring.

Nekton scientists say the Ranger microAUV is about 39 inches long, weighs about 11 pounds, and uses a different guidance system from the MicroHunter. The Ranger "is autonomous and is intended for environmental monitoring and other basic missions," Pell says. "We're trying to reduce the number of dollars people have to put into the water to get better higher-resolution data out faster."

Typical Ranger missions might include gathering data to create three-dimensional maps of water column properties, pipeline leak detection, and mine countermeasures. Rangers also could deploy from larger submarine-launched UUVs for high-level search and detection. The large UUVs would launch the microUAVs for close-in detection and classification tasks.

"The purpose of Ranger is to be a stand-alone or individual component of a multi-agent underwater system that delivers a good performance/cost ratio and minimizes its deployment logistics compared to current systems," Pell says. "Ranger is designed for single-user deployment, launch, and recovery, with a user-friendly interface, auto-calibration, and networked inter-vehicle communications."

Nekton officials say they plan to develop and build a fleet of Rangers for testing this year in individual and "swarm" operations modes. While they do not currently envision airdropping the Ranger, Pell says users could deliver them by air, with proper engineering. They are small enough to be carried in a backpack and hand-launched into the water.

The development model currently has a 4-hour operating time, with a speed of about 10 knots. Their goal for operational versions is to run longer and farther, although Pell declines to give specifics.

"Ranger is only the first of a long line of vehicles in that size range that we eventually envision carrying any sensor that will fit into that package," he says.

Further development will enable deployment in groups to create distributed sensor arrays, offering researchers simultaneous or nearly simultaneous data over a large 3-D volume for greater spatial and temporal resolution. Pell predicts such a wide-area array approach will greatly expand the possibilities for underwater sensing, while freeing up people, ships and other resources for other tasks.

For more information contact Nekton Research by phone at 919-405-3993, by fax at 919-405-3994, by e-mail at info@nektonresearch.com, by post at 4625 Industry Lane, Durham, N.C. 27713, or on the World Wide Web at http:/ /www.nektonresearch.com/.

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