High-Resolution 3D Laser Imaging for Inspection, Maintenance, Repair, and Operations

Abstract

Abstract In January 2011, 3D at Depth was awarded a RPSEA contract to bring high-resolution three-dimensional (3D) laser imaging technology from the lab into an underwater environment for the oil and gas industry. Throughout the project, CDL Inc. provided expert engineering support and materials to marinize the system. Thus far the project has included design of the core technology for reliable operation in a deep-water environment; pool testing; reliability testing; integration with a work-class ROV; demonstration in a ROV test tank; and turbidity testing. Open water testing is to commence in the first half of 2013. 3D laser imaging is a powerful data collection system that provides 3-D information for a specific area of interest. It is the predominate technology for terrestrial survey, construction, as-built analysis, and large-scale retro-fits. The 3D laser imaging market is a mature multi-billion dollar industry with an eco-system of software, expertise, and best practices. Developing the technology to provide high-definition subsea laser imaging enables the deep water industry to use the current state of the art in 3D metrology and related best practices developed for the terrestrial market. This paper builds on last year's paper (OTC 23006-PP) and will discuss updates to the system and demonstrations that have occurred over the last year. Top of the line terrestrial laser scanners produce cm spatial and range accuracy at up to one- hundred meters range. Due to the absorption of water, realizable deep-water systems are limited to tens of meters range depending on the target and water conditions. To our knowledge, this is the first time millimeter class measurement accuracy will be demonstrated at greater than 8m range for an underwater laser system mounted to a ROV. This technology is essential for improving the safety and reliability of deep water assets. The lack of timely and accurate survey-quality 3D measurements poses an integrity management challenge for such assets. A lack of accurate data results in either higher risks or higher costs to build and maintain environmentally safe production and product transportation systems. The speed and precision of the technology developed by this project reduces operating costs for underwater inspection, maintenance, and repair; reduces environmental risk through more accurate inspection; significantly improves construction practices and quality / reliability; reduces risks to high value assets; and provides rapid access to sharable survey-quality as-built data before, during and after construction.