Rov in The Future

How current subsea inspections technologies are transforming the industry

The world of subsea inspections has drastically changed over the last 5 years and continues to do so as it adapts to the new challenges offshore operators face. The integrity of subsea installations has always been one of the most strategic topics and the maintenance of it is of great significance in order to ensure production. The ever-increasing squeeze in energy prices has built more pressure for operators to find faster, more accurate and more cost-effective means of inspections yet ensuring their assets remain operational at all times. New technologies are transforming the way data is captured, analysed, transmitted and visualised to support this.

Technology is paving the way into a future where this is a reality. Organizations that embrace what these new technologies have to offer have a lot to gain that can transform their operations. Yet many operators face the challenge of not knowing what new tech is out there and whether it’s suitable for their business. In order to understand the current landscape of technologies one has to explore how this technology has evolved over the years, the current state of play and what technologies could shape up the future.

ROVs serving us for 40+ years.

For the last 4 decades, inspections of subsea assets have mainly been carried out by Remotely Operated Vehicles (ROV) that are piloted on the sea’s surface from a dedicated boat. There were two significant problems being faced when ROVs where operated: the growing cost of carrying out these inspections and the shortage of these conventional inspection resources.

The cost of inspection has traditionally been high as a result of the large vessels used to carry out the inspection work resulting in a significant number of crew needed for the operation. Footage from the ROV was captured in the field, with data stored locally on the vessel and then given to the engineers back at HQ for analysis. The time to access the captured data was often delayed by days to months for use and couldn’t’ be leveraged efficiently for organizational learning and operational improvement. Furthermore, data that was captured was of use only once and couldn’t easily be stored & accessed in a format that would enable future decision making and assessments. Fast forward 40 years and innovations are now key weapons in the fight to eliminating risks and human error from the offshore subsea inspection process.

Technological innovation

Bringing onshore tech into the subsea

To bring innovation and improved inspection and data captured techniques the ROV industry has traditionally looked at the onshore inspection methodologies and technologies for inspiration. Image based mapping (IBM) and 3D photogrammetry are technologies that traditionally have been used for surveying on land assets. These technologies are quickly gaining traction within the oceanographic community as cost effective means to carry out subsea surveys.

Many comparisons have been drawn between IBM and traditional laser scanning techniques including Light Detection and Ranging (LiDAR) to determine the accuracy, limitations and advantages of both methods when applied underwater. Previous studies have compared IBM and laser scanning when airborne and although the findings proved to be impressive, when used for subsea exploration, IBM proved to be the more reliable of the two.

When considering LiDAR or photogrammetry, both offer advantages and disadvantages – the choice is really determined by the environment, terrain, and the size of the area. LiDAR works in a similar way to sonar and radar but uses light instead of sound or radio waves to measure distance, whereas photogrammetry uses scaled high-definition pictures. For mapping and surveying bare earth regions, photogrammetry is a great choice, but for areas with heavy vegetation or other obstructions, LiDAR provides the best fit.

One of the biggest advantages of image based 3D photogrammetry is that it allows for smaller ROVs to move with greater freedom, while still maintaining very high fractions of millimetre accuracy over long ranges. This provides a solution for full freedom of movement around an asset as if it were frozen in time to paint a clearer picture of a subsea environment.

Most laser based systems require a stationary platform, or integration with subsea positioning devices, resulting in lower definition footage at a greater cost. It also requires several relocations to cover long distances and manual intervention to piece together data.

3D photogrammetry delivers many operational benefits, enabling offshore construction, condition monitoring and decommissioning surveys with fewer people and smaller vessels. 3D point clouds can be streamed via a satellite link, unlike video which can be constrained by bandwidth, further reducing the need for personnel offshore.

It enables accurate measurements to be taken where previously unreliable estimations were used. Proving the feasibility of this technology and providing a step change in efficiency and safety for hazardous and extreme offshore subsea environments.

From small environmental surveys to large-scale mapping – the scope for using IBM technology is huge. And when assessing subsea assets for damage, corrosion or determining levels of marine growth, the speed and precision of IBM far outweighs LiDAR.

What does the future hold for ROVs?

Future ROV tech will continue to support ways of faster, more accurate and more cost-effective inspections. There is an increasing demand for offshore subsea inspection, from Oil & Gas Decommissioning to the Renewables industry. This future can be a reality with the uptake of Artificial Intelligence (AI) and Autonomous Underwater Vehicles (AUV) inspections all supported by modern technologies. The adoption of this technology can pave the way for:

Lowering costs: a AUV will be able to carry out an inspection significantly quicker than an ROV which will result in lower cost of operations
Improved control over HSE: by eliminating the need for ROV pilots, smaller vessels can be used which reduces the overall carbon footprint of the vessel as well as lowering the amount of crew exposed to lifting operation risks

Enhanced quality: Post processing 3D data will enable a quicker way of inspecting the assets, enabling more informed decision making.

The ROVs of the future will be untethered to improve manoeuvrability and have the ability to send data wirelessly back to the operators on the ship on nearshore. Being autonomous means they will be able to navigate without human control, not only be able to monitor assets more effectively but also, over time and with machine-learning, create models of these assets that can accurately assess their lifetime condition.

Conclusion

ROVs continue to evolve to meet the needs of the industry as over $500 billion of assets is currently working on the seabed and all of it needing periodic inspection, maintenance or repair. With the ever-increasing need for inspection of these assets, 3D image modelling is the future of survey delivered by autonomous subsea vehicles.