Sure, bathymetry has been a market for years, and the mapping of sea floor beds is pretty much old hat, but high-precision 3D scanning and modeling of underwater assets? That’s something that’s growing in a hurry.
Much of the demand is coming from the offshore drilling industry. As demand for new sources of petroleum increases, and the offshore market has more rigorous demands for safety and spill prevention following the Deepwater Horizon incident, so too is demand increasing for better information to both reduce risk and create efficiency. Sure, they’re doing it above water, making sure drill bits don’t meet with interference and that all the giant moving pieces offshore line up correctly, but they’re also doing it underwater, making sure that pipes that are fabricated on land fit snugly when the installation process begins.
A report from the Offshore Technology Conference happening this week, from JPT Online, highlights how this is being applied:
Lockheed’s AUV was mated with a sonar scanning system and used to create a detailed map of an old Chevron platform in the Gulf of Mexico. It created the 3D image while the craft spiraled around the platform, which shows signs of age. The test concluded that it spotted all the platform’s anomalies, such as bent beams. The scanning took 40 minutes, a fraction of the time it would have taken using older technology. The deepwater test program was able complete all the tasks it had planned to do in six days instead of the planned three weeks, said Jacobson.
Other RPSEA-supported projects that apply new ways of creating 3D images, with data from scans imported into software commonly used for digital model making, are pushing a new generation of sonar and laser methods offering better and quicker imaging.
Six days vs. three weeks is a nice savings, indeed. Of course, I can’t be sure from the article, but I suspect they’re using BlueView technology here. Attendees at last month’s SPAR International conference saw a very impressive presentation from BlueView on how their technology is being applied in the petrochemical sector. Here’s an example of their technology being combined with an ROV (remotely operated vehicle vs. the AUV, which is autonomous, referred to above) to inspect a downed offshore rig:
In this case, multiple overlapping scans were collected from a Schilling UHD ROV and then registered with Leica Geosystem’s Cyclone software without the aid of any position or navigation data. According to BlueView’s Ed Cheesman, control can be put out as well, in the form of large spheres, which helps with the registration and leads to increased accuracy.
“We were getting three to five cm translational accuracy,” he said, “over about 30 meters. Most specs say they want 10 cm over 40 meters.”
The job Cheesman presented at SPAR was the company’s first in the petrochemical sector, done for Fairfield Energy in the North Sea. The company needed to build what’s known as a spool piece and then install it underwater.
“We needed to know how long is the piece of pipe they need to make and what is the orientation of the two flanges,” Cheesman said. “They actually built the spool piece from the measurements we took, and then they scanned the spool, and then they did a test run with Cyclone, and then they installed it. Most importantly, the spool fit.”
I’ve got some information on 3D being used for underwater bridge inspection as well. Look for that in a follow-up post.
