Powered Tow Body Operations

摘要

The Powered Tow Body (PTB) is a new class of vehicle that combines a conventional tow body and an Unmanned Underwater Vehicle (UUV) into a powered, towed UUV. The PTB is both towed by the surface craft and propelled by its on-board propulsion system. Power is sent down the tow cable from the surface craft to the PTB. The PTB propels itself forward, introducing a "hook" in the catenary of the tow cable. The "hook" increases the steadiness of the PTB by reducing the transmission of forces and motions from the surface to the tow body. The increased steadiness means that side scan sonar, synthetic aperture sonar, and other motion-sensitive payloads can operate effectively even when towed from smaller craft such as Unmanned Surface Vessels (USV). This approach has several advantages for survey operations. The first is endurance. Mission endurance increases, because it is limited by diesel on the boat and not the batteries onboard the vehicle. Further, more power is available to the payload sensors. Second is data availability. Similar to a conventional tow body, sensor data can be examined or communicated real time without waiting for the vehicle to return to the ship. Third is weight. The PTB achieves depth using forward thrust and not weights or depressors, simplifying launch and recovery. Finally, with the addition of batteries, the same vehicle can be used as a UUV, providing a broad range of capabilities with a single vehicle.