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Lockheed Martin Corporation is conducting a multi-year technology developmentprogram to advance the state of the art of Autonomous Underwater Vehicle (AUV)inspection technologies for the offshore oil & gas industry. The scope ofthis project is to develop and demonstrate AUV technologies for conductingautonomous structural survey and inspection of subsea facilities for a widerange of applications, including pre/post-hurricane inspection of offshoreplatforms, pre/post-decommissioning structural survey, and deepwater facility /riser inspection. This paper will describe the results of Lockheed Martin'srecently completed technology demonstration project, Autonomous Inspection ofSubsea Facilities, including laboratory simulation, local offshore trials, andtechnology validation trials in the Gulf of Mexico against offshore productionplatforms. This project was jointly funded by the Research Partnership toSecure Energy for America (RPSEA), Lockheed Martin and sea trials weresupported by Chevron Energy Technology Company Capabilities demonstrated duringoffshore trials included (1) autonomous real-time three-dimensional (3D)imaging and modeling of an underwater facility, (2) detection and highlightingof changes to the facility in real time, and (3) feature-based navigation, theaiding of the AUV's navigation along its path based on feature detection andrecognition. The paper will describe the results achieved, and will highlightthe performance improvements over current platform inspection methods, including significant improvements in operating efficiencies, and thedevelopment of highly accurate 3D models for use in structural integritymanagement. Finally, the paper will outline the potential benefits of evolvingAUV and sensor technologies for applications such as structural survey, pipeline inspection, subsea facility inspection, and light intervention, including potentially game changing improvements in cost, performance, safetyand reliability that will enable more cost-effective operations in deepwaterand/or remote subsea fields. Introduction Subsea Integrity Management is defined by the Energy Institute Guidelines forthe Management of Integrity of Subsea Facilities as " the management of a subseasystem or asset to ensure that it delivers the design requirements, and doesnot harm life, health or the environment, through the required life." A keyelement in any integrity management program is regular in-service inspections. As the industry moves into deeper and harsher environments, challenges faced byoperators include the high cost of subsea inspection and the limited inspectionintervals available. Inspections provide a snapshot of the structural health ofthe system. Integrity management practices in deepwater fields rely heavily ongeneral visual inspection of subsea equipment. Remotely operated vehicles(ROVs) and divers are the primary means used today to conduct inspections -ROVs exclusively in deepwater (greater than 100-meter water depth) and diversgenerally limited to less than100-meter water depth. In both cases supportvessels larger than 70 to 100 meters with support crews numbering more than 30and with 100+ tons of equipment are required to collect the simplest visualinspection record. The quality and usefulness of the records are highlydependent on the seawater's visual clarity, illumination, camera and recordingequipment, and ROV or diver stability. An ROV inspection of a deepwaterfacility can provide visual evidence of structural degradation, impact damage, corrosion, valve damage, leaks, vibration, and other structural damage (Figure 1). Benchmarking the condition of subsea equipment following installation andtracking its status over time can provide a history of the deterioration rate. Video inspections include: well heads, valve positions, pipeline endterminations (PLETs), pipeline end manifolds (PLEMs), underwater terminationmanifolds (UTMs), flowlines, jumpers, moorings, risers, and associated cablingand equipment on the sea bed. This equipment is often spread over many squarekilometers requiring the support vessel to maneuver in DP mode for days. Inspection speed is totally dependent on the coordinated movement of the ROVand support vessel and the skill of the ROV pilot.

Emerging autonomous underwater vehicles (AUVs) developments across the oil and gas industry now include pipeline inspection; structural survey; deepwater inspection, repair and maintenance (IRM); and field resident systems for remote/harsh environments. As these capabilities mature, AUVs will become an increasingly important tool for deepwater field operations. Early adoption of AUV standards will facilitate more rapid deployment of AUV technologies and enable the industry to reap a wide range of safety, environmental, operational, and economic benefits for its deepwater fields. The development of industry standards for AUV interfaces will facilitate more rapid implementation of AUV capabilities and lead to more cost-effective, compatible system designs by AUV vendors and field hardware manufacturers. The development of regulatory standards for the interpretation and acceptance of autonomous inspection results is also an essential step toward the achievement of more cost-effective operations and regulatory oversight of deepwater subsea fields. This paper describes a future vision for the use of AUVs in deepwater field operations, the benefits to be realized, and the future capabilities of AUVs that must be anticipated and facilitated within AUV standards to achieve that vision. Additionally, this paper describes the goals and objectives of DeepStar Project 11304, which is laying the groundwork to achieve accelerated standardization of AUV interfaces and the development of regulatory standards for AUV inspections.

Advances in autonomous inspection of deepwater subsea facilities are examined to illustrate the favorable enhancement of safety, reliability, reduction in risks, economic benefits and superior data products compared to conventional means. These benefits provide operators with significant improvements over general visual inspection by the addition of sensors that produce 3D models of the structure being inspected. Examples are provided illustrating test data from operations conducted from 2011-2013.Additional benefits include rapid response when a loss of well containment requires large standoff distances between the host vessel and the sensing platform. Three dimensional georegistered models of the entire scene can be rapidly collected within hours of the incident providing responders with a clear vision of the underwater scene along with in-situ status of critical components.Introduction of new sensors support even more advanced capabilities leading to autonomous metrology, hydrocarbon detection tracking and fingerprinting, non-contact corrosion potential measurement, thermal measurements and three dimensional underwater scanning lasers.Application to deepwater life of field inspection will be presented with evidence gained from offshore trials in 2011 and 2012. This emergent technology supports Subsea Facility Inspection Repair and Maintenance, Integrity Management Inspections of Marine Risers, Moorings and anchors, Subsea Pipelines, Flowlines, Umbilicals, and supporting subsea infrastructure.

Integrity Management of deepwater fields requires routine general visual inspections of critical infrastructure. To date the only means of conducting general visual inspection is through the use of ROVs. Deepwater ROV spreads are large and heavy requiring large support vessels with dynamic positioning capability and a significant number of personnel at sea. The capabilities of unmanned underwater vehicles have been enhanced through developments in Autonomous technology progressing to the point that autonomous underwater vehicles can now routinely conduct general visual inspection of subsea facilities. Benefits of Autonomous inspection include: Reduced cost of operations Faster inspection Automatic Change Detection Georegistered inspection data Simultaneous operations from a single support vessel Large standoff distances from the facility being inspected Increased safety of operations Reduced environmental impact Reduced specification requirements on support vessel o Smaller footprint o Dynamic Positioning not required 2 OTC 22438 o Fewer personnel at sea o Reduced Mobilization Costs o Faster response to emergency inspections Lockheed Martin's Marlin ™ Autonomous Underwater Vehicle recently completed a series of tests in the US Gulf of Mexico demonstrating autonomous change detection of a fixed offshore platform. Examples of the Marlin's capabilities from these tests are illustrated. Deepwater Field Owners now have a new tool that can bring significant operational and financial benefits to Life of Field Integrity Management.