Autonomous Underwater Vehicle. A small unmanned submarine. Unlike a remotely operated vehicle (ROV), it can function without a physical connection to the surface.
Autonomous Underwater Vehicle BLN Breach Lane Navigation BMDA3 Battlespace METOC Data Acquisition, Assimilation, and Application
Autonomous Underwater Vehicles are underwater robots that are not remote controlled and operate with artificial intelligence. Just like ROVs they are used instead of divers for difficult operations, e.g. on great depth. More info.