The Knifefish is an

autonomous In developmental psychology and moral, political, and bioethical philosophy, autonomy, from , ''autonomos'', from αὐτο- ''auto-'' "self" and νόμος ''nomos'', "law", hence when combined understood to mean "one who gives oneself one's ...

unmanned underwater vehicle Unmanned underwater vehicles (UUV), sometimes known as underwater drones, are submersible vehicles that can operate underwater without a human occupant. These vehicles may be divided into two categories: remotely operated underwater vehicles (RO ...

(UUV) under development by General Dynamics Mission Systems and

Bluefin Robotics Bluefin Robotics is an American robotics company, headquartered in Quincy, Massachusetts, which specialises in the design and manufacture of military and civilian autonomous underwater vehicles (AUVs) and related technology. The company was foun ...

for the

United States Navy The United States Navy (USN) is the maritime service branch of the United States Armed Forces and one of the eight uniformed services of the United States. It is the largest and most powerful navy in the world, with the estimated tonnage ...

. It is a propeller-driven

minesweeping Minesweeping is the practice of the removal of explosive naval mines, usually by a specially designed ship called a minesweeper using various measures to either capture or detonate the mines, but sometimes also with an aircraft made for that ...

robot designed to replace the Navy's trained

dolphin A dolphin is an aquatic mammal within the infraorder Cetacea. Dolphin species belong to the families Delphinidae (the oceanic dolphins), Platanistidae (the Indian river dolphins), Iniidae (the New World river dolphins), Pontoporiidae (t ...

s and

sea lion Sea lions are pinnipeds characterized by external ear flaps, long foreflippers, the ability to walk on all fours, short and thick hair, and a big chest and belly. Together with the fur seals, they make up the family Otariidae, eared seals. ...

s after the retirement of the 50-year-old

Marine Mammal Program The U.S. Navy Marine Mammal Program (NMMP) is a program administered by the U.S. Navy which studies the military use of marine mammals - principally bottlenose dolphins and California sea lions - and trains animals to perform tasks such as sh ...

in 2017. The Knifefish was first unveiled at a Navy exposition in April 2012, and was originally intended to operate in concert with the Navy's

littoral combat ship The littoral combat ship (LCS) is either of two classes of relatively small surface vessels designed for operations near shore by the United States Navy. It was "envisioned to be a networked, agile, stealthy surface combatant capable of defeat ...

s (LCS) as part of a specialized counter-mine system.

Design and operation

The robot is a derivative of the

Bluefin-21 The Bluefin-21 is an autonomous underwater vehicle (AUV) developed by Bluefin Robotics for defence, commercial or scientific use. It found its most famous use in April 2014 in the search for the wreckage of the missing Malaysia Airlines Flight 37 ...

, a civilian UUV designed by the

Quincy, Massachusetts Quincy ( ) is a coastal U.S. city in Norfolk County, Massachusetts, United States. It is the largest city in the county and a part of Metropolitan Boston as one of Boston's immediate southern suburbs. Its population in 2020 was 101,636, making ...

-based company Bluefin Robotics. In 2014, the Bluefin-21 gained widespread recognition after it was deployed to search the seafloor of the

Indian Ocean The Indian Ocean is the third-largest of the world's five oceanic divisions, covering or ~19.8% of the water on Earth's surface. It is bounded by Asia to the north, Africa to the west and Australia to the east. To the south it is bounded by ...

for the wreckage of

Malaysia Airlines Flight 370 Malaysia Airlines Flight 370 (MH370/MAS370) was an international passenger flight operated by Malaysia Airlines that disappeared on 8 March 2014 while flying from Kuala Lumpur International Airport in Malaysia to its planned destination ...

. The Knifefish is a

torpedo A modern torpedo is an underwater ranged weapon launched above or below the water surface, self-propelled towards a target, and with an explosive warhead designed to detonate either on contact with or in proximity to the target. Historically, s ...

-shaped robot in length and in diameter, with an operational weight of . It is powered by a

lithium-ion battery A lithium-ion or Li-ion battery is a type of rechargeable battery which uses the reversible reduction of lithium ions to store energy. It is the predominant battery type used in portable consumer electronics and electric vehicles. It also s ...

, which allows it to operate for up to 16 hours on pre-programmed search missions. It uses onboard

synthetic aperture sonar Synthetic aperture sonar (SAS) is a form of sonar in which sophisticated post-processing of sonar data is used in ways closely analogous to synthetic aperture radar. Synthetic aperture sonars combine a number of acoustic pings to form an image wit ...

to detect floating or buried

naval mine A naval mine is a self-contained explosive device placed in water to damage or destroy surface ships or submarines. Unlike depth charges, mines are deposited and left to wait until they are triggered by the approach of, or contact with, any ve ...

s, and can identify a wide variety of mines and mine-like objects using an onboard

database In computing, a database is an organized collection of data stored and accessed electronically. Small databases can be stored on a file system, while large databases are hosted on computer clusters or cloud storage. The design of databases spa ...

and analytical computer. The Knifefish can then mark detected mines and record their locations in its database; the robot later uploads the data to its parent LCS, which destroys 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. The Navy is considering increasing the endurance of the Knifefish to take over minehunting in addition to searching for buried and high-clutter mines. Due to reliability issues with the Remote Multimission Vehicle (RMMV), only 10 will be upgraded and fielded in 2018. The Navy is also pursuing adding a towed sonar to the Common Unmanned Surface Vehicle (CUSV) for fielding in 2020. For certain mine countermeasure missions, the Knifefish is superior to the RMMV, but it doesn't have the endurance to cover large minefields; if endurance can be enhanced, the MCM package would be simplified, as the sensor is embedded in the vehicle rather than towed, and the CUSV would only be used for minesweeping.

Development

By December 2012, the Navy had ordered eight Knifefish units, at a total cost of US$20 million. 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. The Knifefish was scheduled to begin sea trials in 2015, and to enter into active service in 2017, coinciding with the end of the Navy's

. Sea acceptance testings were completed off the coast of

Massachusetts Massachusetts (Massachusett language, Massachusett: ''Muhsachuweesut assachusett writing systems, məhswatʃəwiːsət'' English: , ), officially the Commonwealth of Massachusetts, is the most populous U.S. state, state in the New England ...

in 2018. On 20 July 2020, the U.S. Department of Defense awarded General Dynamics roughly $13.5 million for ongoing engineering on the Knifefish.

References

External links

Bluefin Robotics website
* * {{General Dynamics Mission Systems Unmanned underwater vehicles Military robots Mine warfare countermeasures General Dynamics Mission Systems Equipment of the United States Navy Robots of the United States