Clients require accurate positioning and DOB data for their subsea pipelines, as well as accurate multibeam data for the seafloor topology.
The rental market for subsea pipe trackers is quite bare. The TSS660 pipe tracker is currently one of the two main purchasing options available on the market and is designed ideally for use on a larger ROV.
We decided to trial the TSS660 on our observation class size Blue Volta eROV – the world’s first ROV to be developed specifically for deployment from a USV. In winter 2021, in the Dutch sector of the North Sea, we deployed the Blue Volta from our 12 m USV, Blue Essence. This proved to be a fast, safe and cost-effective solution.
The eROV and USV pilots found that when the USV went faster, maintaining the heading became easier. But when the vessel went too fast, this impacted on data quality. The pilots of both systems quickly learned how to work together to achieve the optimum speed and position, to gather accurate and high-quality pipeline data.
The data was collected around the clock; our onshore remote operations centre (ROC) in Holland covered the day shift and our ROC in Aberdeen covered the night shift. Despite the harsh winter weather conditions, we completed multiple pipelines DOB data. This ability to gather high-quality data on a 24/7 basis is a huge benefit for any offshore project working to tight project timescales.
The USV gathered data at up to 1500 m an hour, which is comparable to the speed achieved by standard crewed inspection vessels, which typically have around 90 people onboard. The potential cost savings and reduced carbon footprint for clients are huge. For example, even efficient conventional survey vessels use approximately 7,000 litres of fuel a day, compared to our USV and eROV solutions significantly lowering its carbon footprint, by consuming 200 litres per day. All completed with no offshore personnel involved, the safety risks are dramatically reduced.
I have been amazed at the control and power of our eROV system and its ability carry out the depth of burial pipeline survey.
We are working to develop a small and slimline DOB solution on a ‘skid’ that has the same footprint as the eROV, to give us a more compact, hydrodynamic and stable solution during survey operations. This stability will aid improvement in data quality and efficiency.
We are also exploring new ways to follow the subsea pipeline autonomously. Fusing the feedback from the pipe tracker directly into our flight control system. This will eradicate latency and pilot errors.
The Holy Grail of DOB inspections with a small observation class vehicle is to obtain DOB data and a good swathe of quality positioning multibeam echosounder (MBES) data simultaneously. To this end, we will continue our search for the ultimate single-pass pipeline inspection operation that combines our USV and eROV equipped with multiple state-of-the-art sensors. Our innovation teams are busy driving their focus towards a faster, safer, cost-effective pipeline inspection solution.
Fugro Blue Volta fitted with the TSS660 pipe tracker
Our inspection, repair and maintenance services; monitoring and remote systems technologies; and diverse testing and engineering capabilities support the long-term safety, integrity and performance of marine assets.
With the maritime industry transitioning to remote and autonomous operations, the need for safe, efficient and sustainable remote inspection is ever-growing.