Subsea technology companies demonstrated a new underwater surveying technique that could significantly shorten the time needed to map underwater structures and offshore sites. The event was organized by DOF Subsea to showcase the capabilities of dynamic mobile mapping. The new technique uses a 3D laser scanner fitted to an ROV to create highly detailed, point cloud images of subsea assets and environments. By combining the 3D laser data with precise underwater acoustic and inertial navigation information, it is now possible to generate centimeter resolution engineering models from which accurate measurements can be instantaneously and repeatably captured.
In conventional marine construction support terminology, metrology is the work done by surveyors and ROV to acquire various subsea measurements, typically between flanges on separate pieces of subsea infrastructure. These measurements allow precise fabrication of subsea jumpers and spool-pieces. Traditionally the vessel time to acquire the measurement data can take between six and eight hours per metrology. The adoption of a smart combination of proven technology can reduce data acquisition (and hence vessel) time to around two hours.