Autonomous underwater vehicles can work for a long time without getting tired and at depths impossible for a diver. Divers can operate typically up to 60 meters, requiring use of special gases and tools when operating at higher depths. Additionally, the time divers can spend at such a high depth is quite limited. The sea bottom is deep (up to 11,000 meters) and many installations are below the operating depth of divers, such as oil rigs or communications pipelines.