Kongsberg has finished the longest multi-sensor AUV pipeline assessment. Two subsea pipelines connected to the oil refinery at Mongstad was inspected using the HUGIN 1000 Autonomous Underwater Vehicles (AUV).
The HUGIN 1000 was controlled from the HNoMS Maloy, the Royal Norwegian Navy vessel while the inspection was held in Hjelte fjord near Bergen from 9 to 11 February, 2011.
Equipped with the EM3002 multibeam echo sounder, HISAS 1030 synthetic aperture sonar and an optical camera with LED lighting, the HUGIN 1000 inspected about 30 km of the subsea pipelines on a two-pass mission lasting 8 h.
During the first pass, the HISAS 1030 sonar tracked and detected the pipelines using the PipeTracker software, which was developed in tandem with the Norwegian Defence Research Establishment (FFI). During the second pass, the HUGIN 1000 used the optical camera and the EM 3002 multibeam to inspect the pipelines by following the pipeline tracks previously identified. The recorded data was post-processed into bathymetry maps of the pipeline and high-resolution sonar images. The complete process was applied to the second pipeline with the same time frame.
Maintaining a steady speed of 4 knots at 4-25 m altitude with a water depth of 180-560 m, the two pipelines were inspected at a faster pace using the HUGIN 1000. Moreover, the robust design of the HUGIN 1000 ensures smooth operation at low altitude and high speed with clear images from the camera.