Knifefish (robot)

The Knifefish is an unmanned underwater vehicle (UUV) under development by General Dynamics Advanced Information Systems and Bluefin Robotics for the United States Navy. It is a propeller-driven minesweeping robot designed to replace the Navy's trained dolphins and sea lions after the retirement of the 50-year-old Marine Mammal Program in 2017. The Knifefish was first unveiled at a Navy exposition in April 2012, and is intended to operate in concert with the Navy's littoral combat ships (LCS) as part of a specialised counter-mine system. The Navy plans to begin sea trials of the Knifefish in 2015, and to enter it into active service in 2017.

Design and operation
The robot is a derivative of the Bluefin-21, an earlier unmanned vehicle designed by the Quincy, Massachusetts-based company Bluefin Robotics. The Knifefish is a torpedo-shaped robot 19 ft in length and 21 in in diameter, with an operational weight of 1700 lb. It is powered by a lithium-ion battery, which allows it to operate for up to 16 hours on pre-programmed search missions. It uses onboard synthetic aperture sonar to detect floating or buried naval mines, and can identify a wide variety of mines and mine-like objects using an onboard database and analytical computer. Detected mines will then be marked and their locations stored in the Knifefish's database; the robot will later upload the data to its parent LCS, which will destroy the mines. The Knifefish may be modified to transmit its data in real-time, if the Navy considers such a capability necessary after the robot's sea trials. Each LCS will be capable of operating two Knifefish UUVs, which will scan the seabed near the ship and reduce the risk of mine damage to the LCS itself.

Development
Eight Knifefish units had been ordered by December 2012, at a total cost of US$20 million. They are scheduled to begin sea trials in 2015, and to enter into active service in 2017, coincident with the end of the Marine Mammal Program. In April 2013, General Dynamics completed its critical design review of the Knifefish, and began developing software and hardware for the operational version of the robot.