Untethered autonomous underwater vehicle (underwater autonomous robot), also known as underwater autonomous vehicle. Unlike the ROV, the AUV has no physical connection to the mother ship. It relies on its own power and the intelligent autonomous navigation of the machine. Unlike the ROV, the AUV is connected to the surface mother ship by the umbilical cable, which requires both downward transmission of power and real-time two-way transmission of control signals.
Compared to ROVs, AUVs have the advantages of a wide range of activities, greater diving depth, no umbilical entanglement, access to complex structures, no need for a large surface support system, small deck footprint, and low operating and maintenance costs. However, due to the limitation of relevant technology development level, AUVs are not as mature as ROVs at present.
The AUV is an ideal instrument platform for obtaining high quality data and images that cannot be obtained by conventional means due to low noise emission and the ability to get close to the object to be observed (such as seabed terrain tracking at a set altitude). Combined with low cost, good concealment and high safety (unmanned), AUVs are gradually becoming an important means of ocean observation and exploration. It is widely used in Marine scientific investigation, exploration and development of Marine resources, maintenance of underwater structures, laying of submarine oil and gas pipelines, submarine hydrothermal research and military applications. Auvs have been successfully applied to the exploration of offshore oil and gas, gas hydrates, polymetallic nodules and hydrothermal sulfide deposits and other Marine mineral resources.(From Solid Buoyancy Materials)