Autonomous underwater Vehicle or AUV

It is a self-propelled, unmanned, untethered underwater vehicle capable of carrying out activities with little or no human supervision.
AUVs are often used as survey platforms to map the seafloor or characterize physical, chemical, or biological properties of the water.
A large variety of AUVs are for employing the ability to obtain superior data quality, obtaining high-resolution maps of the deep seafloor, or to establish a pervasive ocean presence, for example, using many small AUVs to observe oceanographic field