Autonomous Vehicle Maps the Arctic Seafloor

Far above the Arctic Circle, an autonomous surface vehicle set out to map the seafloor in an effort to improve nautical charts in areas where there is scarce data and vessel traffic is increasing.

A team of engineers and students from the University of New Hampshire’s (UNH) Center for Coastal and Ocean Mapping, together with personnel from NOAA’s Office of Coast Survey, recently returned from an Arctic voyage that deployed an unmanned surface vehicle (USV) from the NOAA hydrographic ship Fairweather, a first from a NOAA vessel in the region.

The Fairweather spends each summer surveying the seafloor in West Coast and Alaskan waters to improve the nation’s nautical charts. In the Arctic, many of these charts are built from scant sounding data, often from measurements that are hundreds of years old, because there is no additional data. As summer shipping increases in Arctic waters, a national effort is underway to improve the charts to ensure safety, but short summers, limited good weather, remote locations and the vast amount of seafloor to survey makes for a daunting task.

Now, as the capabilities of autonomous survey systems are rapidly advancing, developing autonomous system technology and procedures is a key piece of Coast Survey’s autonomous systems strategy, which ultimately targets more efficient and effective data acquisition.

The robotic boat that was deployed on this summer’s voyage, UNH’s Bathymetric Explorer and Navigator (BEN), increased the survey coverage of the ship’s efforts by as much as 25 percent during day operations alone, and if integrated into the ship’s routine production survey operations could be operated by existing shipboard personnel.

BEN is a robotic vessel designed to aid the ship’s crew in the colossal task of seafloor survey. It was co-designed by UNH engineers and its manufacturer, ASV Global Inc. based in Houston. It is 4 meters long, has a top speed of 5.5 knots and a 16-hour endurance. Autonomy software operated aboard the vessel is a combination of open-source robotic operating systems and software developed by engineers Roland Arsenault and Val Schmidt at the center to tailor BEN’s behaviors for hydrographic seafloor survey. BEN is outfitted with state-of-the-art sonar and navigation systems to meet the seafloor survey requirements for nautical charting and safety of navigation. The navigation system provides exact positioning and attitude while BEN plows the ocean’s surface, while the sonar paints a swath of measurements below and to the sides of the vessel.

On Saturday, July 28, the Fairweather made the first successful launch of a USV for an operational hydrographic survey from a NOAA vessel in the Arctic. The team conducted four additional deployments, including an extended overnight survey made in coordination with the ship.

In this proof-of-concept expedition BEN operated daily along with the ship’s manned survey launches. The two-person team of BEN’s operators, which included engineer Andy McLeod, graduate student Lynette Davis along with NOAA hydrographers from the ship’s crew, stayed aboard the Fairweather.