In a somewhat bizarre, but still pretty cool plan to help defend their ports and ships, the United States Department of Homeland Security (US DHS) is funding the development of BIOSwimmer, an unmanned underwater vehicle (UUV) shaped like — of all things — a tuna.

The tuna was picked because that species has evolved into one of the fastest and most maneuverable fish of their size. The positioning of the tuna's dorsal and pectoral fins, as well as its basic shape and mode of swimming, will give BIOSwimmer the speed and maneuverability to search and inspect areas where previous UUV designs have had difficulty.

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Unmanned underwater vehicles are divided into two types: ROVs are Remote Operated Vehicles that are controlled by a human operator on a ship or on land that tracks the location of the vehicle and can see what it sees. AUVs are Autonomous Underwater Vehicles that are a type of robot, operating without the regular human input. BIOSwimmer falls into the latter category.

Developed for the DHS by Boston Engineering Corporation's Advanced Systems Group (ASG) in Waltham, Massachusetts, BIOSwimmer will be able to enter the flooded bilges and tanks of ships, easily maneuver around ship propulsion and steerage systems, and enter or inspect sea chests, looking for threats to national security and potential invasive species.

"It's all about distilling the science," says David Taylor, program manager for the BIOSwimmer in the DHS Science and Technology Directorate's Borders and Maritime Security Division. "It's called 'biomimetics.' We're using nature as a basis for design and engineering a system that works exceedingly well. Tuna have had millions of years to develop their ability to move in the water with astounding efficiency. Hopefully we won't take that long."

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