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During this fnal phase of testing, provide a next generation tool for struc- offshore testing of the prototype 3D tural integrity management.

laser imaging hardware and software are The long-term benefts of AUV-based being conducted in local offshore waters laser imaging for structural integrity man-

Subsea adjacent to Lockheed Martin’s Palm Beach agement could be signifcant. First, the facility. The objectives are to demonstrate feld operator reaps the benefts that AUV 3D laser images from a mobile AUV with inspections can offer over current ROV accuracies at the sub-centimeter scale, and inspection methods for deepwater felds, to prove that AUV-based 3D laser imaging including smaller vessels, smaller crew,

Lockheed Martin’s Marlin AUV will be is a viable alternative for inspection of and elimination of the ROV umbilical. outftted with a 3D laser for ofshore subsea structures such as trees, jumpers, These benefts translate to lower overall trials 1Q 2014. Photo: Lockheed Martin.

pipeline end terminations, manifolds, life-of-feld cost for structural integrity pipelines, fowlines, risers, and moor- management, and will enable more ing lines. Tests include AUV-based laser frequent inspections at an affordable cost. imaging of mock-up test fxtures and/or Autonomous 3D modeling and change local wreck sites using the Marlin AUV detection can also positively affect accu-

Marlin Mk3 preliminary that represents the same operational test racy and operational effciency. Not only specifcations cases as those evaluated in Lockheed’s do inspections become more effcient, but

Wet weight – 350lb simulation laboratory. AUV-based 3D also, factors such as human fatigue and (160kg) laser imaging can perform a wide range inspection data overload are eliminated

Payload 3 3 capacity

Volume – 20ft (0.57m ) of inspection tasks, including generation from the equation.

Power – 4kw peak of geo-registered “as-built” models of The availability of detailed 3D models structures on the seabed or in the water from prior surveys can beneft structural 33 hours (mission

Endurance column, periodic survey of subsea infra- analysis and defect evaluation, and the dependent) structure and comparison against a base- application of third-party software tools

Speed 0-5 knots line model, and autonomous detection from other industries, such as terrestrial

Range 100nm (185km) of structural defects or other out-of-spec survey, will also enable increased opera- conditions that exceed threshold values. tional effciency.

Depth 13,124ft (4000m) rating

Once an out-of-spec condition is AUV-based 3D laser imaging has the detected by the AUV’s onboard per- potential to become a transformational

Length 17ft (5.2m) ception autonomy software, a pre- tool for structural integrity management,

Width 3ft (0.9m) programmed “revisit” maneuver can enabling autonomous, real-time high

Height 4ft (1.4m) be invoked to reposition the AUV and resolution 3D modeling, change detection,

Weight 5500lb (2500kg) obtain more video, sonar, and/or laser and structural integrity assessment while in air data. Additionally, such conditions can be offering signifcantly improved safety, automatically fagged to the operator upon may impact pipeline safety using a refer- higher operating effciencies, and reduced completion of the inspection mission. ence model of the pipeline and seabed costs to deepwater feld operators.

This provides the dual beneft of (1) more obtained from a previous baseline survey.

Similar scenarios could be expected rapid and accurate identifcation and John Jacobson is a for AUV-based laser inspection of risers, review of critical conditions by integrity senior program mooring lines, and other subsea infrastruc- management engineers and (2) reduc- manager for ture. In addition, the ability to conduct tion in operator fatigue and subsequent Lockheed Martin’s subsea installation and construction tasks operator errors caused by long hours of Offshore Systems and such as high-accuracy seabed bathymetry, monotonous review of inspection data. Sensors program and jumper metrology, and wellhead vertical-

The future implications of this tech- is based in Houston, ity measurements from a moving AUV nology for structural integrity manage- Texas. He holds a could offer signifcant advantages ment are wide-ranging, with numerous . Bachelor of Science degree in Physics and

Building on the success of its 300m rated potential applications in deepwater a Master of Science degree in Computer

Marlin AUV, Lockheed Martin is currently felds. An example of a potential applica- Engineering from the University of developing a new Marlin variant, the Mk3, tion would be an AUV pipeline inspec- Southern California. which will be capable of operations in tion conducted with 3D laser imaging, water depths up to 4000m. In addition to Dan McLeod is the feature-based navigation, and real-time carrying a full suite of conventional survey deputy director of 3D modeling and change detection. As and inspection sensors such as multi-beam Offshore Systems & another example, a new survey would be sonar, side scan sonar, and HD video, the Sensors at the able to autonomously detect and measure

Marlin Mk3 will employ high-resolution Lockheed Martin, movement of the pipeline, changes in 3D sonar and 3D laser sensors to perform Riviera Beach, pipeline contour (potential buckling or autonomous pipeline inspection and deep- Florida. Mission over-bending), changes in scour, berm water facility inspection. Systems & Training and free span conditions, anode deple-

Business.   He holds a Bachelor of Science tion since the last survey, changes to When completed, the Marlin Mk3 is degree in Ocean Engineering from Florida pipeline surface conditions (pits, cracks, expected to provide deepwater operators

Atlantic University.

dents), and new anomalies or debris that with 3D laser imaging capability that will

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