Unmanned surface vehicles or autonomous surface vehicles ) are boats that operate on the surface of the water without a crew.
Development
As early as the end of World War II, remote-controlled USVs were used in minesweeping applications. Since then, advances in USV control systems and navigation technologies have been achieved, resulting in USVs that can be operated remotely, USVs that operate with partially autonomous control, and USVs that operate fully autonomously. Modern applications and research areas for USVs and ASVs include commercial shipping, environmental and climate monitoring, seafloor mapping, passenger ferries, robotic research, surveillance, inspection of bridges and other infrastructure, military, and naval operations.
Oceanography
USVs are valuable in oceanography, as they are more capable than moored or drifting weather buoys, but far cheaper than the equivalent weather ships and research vessels, and more flexible than commercial-ship contributions. Wave gliders, in particular, harness wave energy for primary propulsion and, with solar cells to power their electronics, have months of marine persistence for both academic and naval applications. Powered USVs are a powerful tool for use in hydrographic survey. Using a small USV in parallel to traditional survey vessels as a 'force-multiplier' can double survey coverage and reduce time on-site. This method was used for a survey carried out in the Bering Sea, off Alaska; the ASV Global 'C-Worker 5' autonomous surface vehicle collected 2,275 nautical miles of survey, 44% of the project total. This was a first for the survey industry and resulted in a saving of 25 days at sea.
Military
Military applications for USVs include powered seaborne targets and minehunting.
A saildrone is a type of unmanned surface vehicle used primarily in oceans for data collection. Saildrones are wind and solar powered and carry a suite of science sensors and navigational instruments. They can follow a set of remotely prescribed waypoints. The saildrone was invented by Richard Jenkins, a British engineer and adventurer. Saildrones have been used by scientists and research organizations like the National Oceanic and Atmospheric Administration to survey the marine ecosystem, fisheries, and weather. In January 2019, a small fleet of saildrones was launched to attempt the first autonomous circumnavigation of Antarctica. One of the saildrones completed the mission, traveling over the seven month journey while collecting a detailed data set using on boardenvironmental monitoring instrumentation. In August 2019, SD 1021 completed the fastest unmanned Atlantic crossing sailing from Bermuda to the UK, and in October, it completed the return trip to become the first autonomous vehicle to cross the Atlantic in both directions. The University of Washington and the Saildrone company began a joint venture in 2019 called The Saildrone Pacific Sentinel Experiment, which positioned six saildrones along the west coast of the United States to gather atmospheric and ocean data.