All AUVs have an integral navigation and control system which works without any human participation. They carry various types of sensors, cameras, and spot lights, along with a GPS system. Apart from this, AUVs also carry sonar, which helps in various functions such as detecting divers, tracking targets, and collecting different underwater parameters. In this way, the AUV can measure the depth, speed, length, and various other specifications of the desired target. AUV collects all these information and sends it to a control and command center located on the shore.
The construction of an AUV is similar to that of a submarine. A small AUV looks like a missile and has a small propeller at the rear for propulsion. A pair of fins is also provided at the sides for stabilization and changing directions. AUVs have a streamlined shape which facilitates moving underwater with reduced stresses.
The navigation of AUVs is generally done by two ways, either on a pre-decided path which is programmed in the AUV or through direction provided by the control and command center. The pre-decided path method is generally used in applications such as pipeline monitoring wherein the route and coordinates are already known. AUVs are generally navigated using the underwater acoustic positioning system, wherein the ship or the control and monitor center is taken as the reference position and the positioning of the AUV is calculated on the basis of GPS data of the reference. All the AUVs run on batteries and have a specific operation period, after which they need to be recharged.