The Magazine for Underwater Professionals
Marine mapping and monitoring with robots
One of the great things about the SUT is the breadth of its areas of interest. It is not constrained to repeat presentations on the same subjects month after month but has the opportunity to explore a range of subjects as varied as the seas themselves.
In a recent London evening meeting, Dr Russell Wynn, chief scientist of Marine Autonomous and Robotic Systems (MARS) at the UK National Oceanography Centre (NOC), provided a presentation on the use of marine autonomous systems (MAS) for marine mapping and monitoring and how robots can be used to meet the needs of science, business and policy.
The NOC is located in Southampton and Liverpool. It is owned by the UK Natural Environment Research Council (NERC) and is responsible for undertaking integrated ocean research from the coast to the oceans. Key activities include ocean observing, seabed mapping and marine survey; data management and scientific advice (for policy making).
At the start of his presentation, Dr Wynn highlighted the increased need for seabed mapping and marine survey data for both scientific and commercial applications. Onshore, we have ordnance survey maps detailing all corners of the UK; offshore there are vast areas of our territorial waters for which there is no reliable survey information.
Historically, most of the NOC’s survey activities have been performed from vessels but these are expensive to maintain and operate. Luckily, there is now an alternative – autonomous marine vehicles – and the NOC has one of the largest fleets of these in the public domain.
Dr Wynn went on to describe the range of vehicles operated by the NOC. These include ROVs capable of diving to the bottom of the ocean and a depth of 6000 metres, torpedo shaped vehicles capable of remote survey operations over extended ranges and durations (including under arctic ice), gliders capable of repeat sawtooth shaped dives through the water column and some recently designed vessels for monitoring surface conditions.
Dr Wynn highlighted some of the survey operations conducted by the NOC using its autonomous vehicles. These included surveys of deep offshore canyons with walls of fragile coral growths and inspections of protected marine areas to establish whether the protection status has been effective, or not.
Of particular interest was the recently conducted MASSMO (Marine Autonomous Systems in Support of Marine Observations) project in which a fleet of unmanned robotic vehicles patrolled the seas off southwest UK in October 2014. Phase 1 of the MASSMO project saw a range of vehicles operating for up to three weeks, carrying sensor loads designed to investigate broad-scale oceanographic and biological processes over the continental shelf up to 150 kilometres offshore. Phase 2 saw the vehicles working close inshore off Plymouth for several days, carrying acoustic receivers to detect tagged fish in and around Marine Protected Areas.
The MASSMO project showcased the potential for unmanned surface vehicles to collect high-quality data from the marine environment; the new Autonaut USV travelled 400 kilometres in 12 days during Phase 1, whilst towing a 25-metre-long acoustic array. The USVs had to operate in challenging ‘open ocean’ conditions, with winds greater than 70 mph (113 kph) and waves greater than seven metres high experienced during Phase 1. Cameras mounted on the USVs captured these stormy conditions, and collected more than 3800 still images and videos including seabirds, floating litter, fishing/naval vessels and a surfacing harbour porpoise.
Dr Wynn concluded his presentation by showing some of the images collected during the MASSMO project. From these, there was no doubting the obvious potential for autonomous vehicles for collecting high-quality scientific and environmental data. After an enthusiastic session of questions from the audience we adjourned to the foyer to refresh ourselves on a generous supply of cheese and wine kindly sponsored by the Leviathan Facility.
Offshore decommissioning was the subject of the North of England Branch meeting held at the International Centre for Life in Newcastle and sponsored by Crondall Energy.
Chaired by Ian Frazer from Crondall Energy, the meeting, attended by more than 60 people, sought to explore the current status of the offshore decommissioning industry and what might lie ahead for it in the future.
The evening was kicked off by Don Orr, the decommissioning assurance manager for BP, who gave an interesting insight into the decommissioning activities in the North Sea looking at the past, present and the future for the industry. With more than 60 platforms removed to date, involving 150,000 tonnes of substructure and 200,000 tonnes of topside, and contracts in place for the removal of Brent and Murchison platforms, it was a clear message that decommissioning activities had certainly started. Looking into the future, there are currently ten decommissioning programmes under consideration by DECC, some of which have a significant subsea content.
Don also presented some of the results from a recent Oil & Gas UK survey of operators’ aspirations for the execution of decommissioning projects. This included collaboration between operators, campaigning across assets, improvements in technology and increasing efficiency as the industry matures. Don finished with a fascinating overview of some of the decommissioning projects BP has recently completed including the North West Hutton pipelines and the Schiehallion FPSO risers.
New technology will undoubtedly have a big part to play in the future of offshore decommissioning. A great example of this being the new Allseas vessel Pioneering Spirit, which was described by Steve Smith, the industry sector manager for Bosh Rexroth. Steve started with an overview of the Pioneering Spirit, which is a colossal catamaran vessel 382 metres long and 124 metres wide, with an impressive lifting capability of 48,000 tonnes. The vessel is capable of removing a jacket structure in a single piece, and lifting a complete topside. Steve presented the details of the topside lifting system, including the lifting beams, central hydraulic unit, the X/Y drive and Z drive systems, together with an overview on how the system is deployed to remove an entire platform topside.
Steve ended up with a view of the future where Allseas is working on the next generation of lift vessels with a capability of 72,000 tonnes.
The evening was rounded off with a presentation by Neil Etherington, the group development director for Able UK, who gave an excellent overview of the challenges relating to the onshore dismantling of offshore platforms and the reuse and recycling activities. Able UK has developed its facilities and capabilities over many years of onshore demolition projects, ship dismantling and offshore platform dismantling projects.
Neil presented some of the details from the dismantling of the North West Hutton jacket (10,000 tonnes) and topside (20,000 tonnes), where the accommodation unit was refurbished and reused as office and welfare accommodation at the Able UK facilities at Seaton Port on Teesside. He also presented an overview of the work planned for the dismantling and recycling of the Brent offshore platforms. This included the plans to take delivery of the complete topside transported from the field to Teesmouth by the Pioneering Spirit and the final delivery by barge to the new quay currently under construction at Seaton Port. The work will involve the dismantling of around 100,000 tonnes of material of which in excess of 97% will be recycled.
The evening highlighted the wide range of activities involved with the decommissioning of offshore facilities and the challenges associated with decommissioning projects. All of the presentations sparked a range of interesting questions and discussion, which was carried on over the buffet dinner.