Page 650 - The ROV Manual - A User Guide for Remotely Operated Vehicles 2nd edition

23.3 Autonomous ROVs 651
FIGURE 23.7
Lockheed Martin’s Marlin AUV.
once the technology is properly integrated, enable faster, safer, and more efficient means of survey- ing offshore platforms and installations compared to traditional methods. They have developed the Marlint AUV (Figure 23.7), a 10 ft long (3 m) vehicle that can carry a 250 lb (113 kg) payload, travel at speeds up to 4 knots, and conduct offshore inspections in less time than ROVs (due to logic-driven operations versus teleoperations), and generate high-resolution 3D geo-tagged models of the surveyed structure within days of survey completion. The Marlin’s advanced autonomy enables safer operations (by requiring fewer people at sea to perform inspections) thus reducing risk to operators. Fully autonomous operations also allow safer vehicle launch and recovery. With its hov- ering capability, the highly maneuverable vehicle is capable of getting into tight places for surveys and inspections. Considering the damage done by recent storms in the Gulf of Mexico (and else- where), there may be considerable work for such systems in the future. During recent surveys in the Gulf of Mexico, the Marlin showcased its ultrahigh-resolution Coda Octopus Echoscopet 3D imag- ing sonar by conducting a structural survey of an underwater platform, allowing for a full 3D sonar point cloud rendering of the target structure (Figure 23.8) in less than 4 hours. Using AUVs equipped with the necessary sensors and instrumentation to conduct surveys of offshore platforms and installa- tions will, once fully integrated, help operators perform more frequent surveys while at sea, receive higher fidelity information, and conduct safer operations compared to using divers or ROVs.
Research conducted by Subsea 7 and SeeByte has resulted in the development of the Autonomous Inspection Vehicle (AIV). Development of the prototype vehicle was done in conjunc- tion with Chevron and BP as part of their AUV Strategic Research and Technology Development Program. The now operational AIV is a battery-powered inspection-class ROV used to conduct effi- cient underwater inspections of subsea infrastructure to include structures, risers, etc. The AIV includes a hydrodynamic design optimized for the demanding subsea environment, a 3D forward-looking sonar,
(Courtesy Lockheed Martin.)