From de-risking to value creation: First Canopus & Ramses LBL solutions deployment on an O&G project

In the summer of 2021, UTEC and iXblue collaborated to successfully provide deepwater remotely operated vehicle (ROV) positioning services for a complex pipelay and structural installation offshore East Africa for a major subsea contractor.

The project was unique for two reasons. This was the first time that UTEC had used the iXblue sparse LBL solution to position ROVs. Moreover, the project saw the first deployment of iXblue’s proprietary sparse LBL technologies for a commercial project in the energy market.

Sparse LBL: Innovative subsea positioning

Sparse LBL is a method that uses inertial navigation system (INS) equipped subsea vehicles and achieves similar or better positioning performance than traditional LBL while using fewer transponders. This is made possible by merging the precise range measurements to an acoustic transponder with the very precise short-term movements from an INS to optimise navigation accuracy.

UTEC has 15 years of experience providing positioning and survey support for hundreds of pipeline and structural installation projects around the world, and has developed industry-leading knowledge and capabilities in subsea positioning systems. This has included supporting the development of sparse LBL positioning, including the use of prototype systems, because UTEC recognised its potential to provide clients significant cost savings over conventional LBL positioning systems.

Sparse LBL positioning only became feasible with the development of commercially available INSs. These use gyros and accelerometers to measure motion. When combined with acoustically measured ranges from seabed transponders, this can provide high-accuracy ROV positioning.

iXblue is a leading manufacturer of fibre-optic based gyro systems, subsea acoustic positioning systems, autonomy systems, and sonar systems. The company’s subsea inertial navigation systems (Octans, Rovins and Phins Subsea) have become standard fit on many ROVs and autonomous underwater vehicles (AUV). iXblue is therefore well placed to offer a complete sparse LBL positioning system. The sparse LBL system works by integrating this hardware and the data as follows:

1. Initially, the vehicle’s INS position has a large error ellipse, represented by the blue circle surrounding the ROV in Figure 1.
2. The ellipse error is then updated thanks to an iXblue Ramses transceiver measurement of the range to first the beacon and its transmission to the INS. The position on the axis between the vehicle and the transponder is now well known.
3. As the ROV moves along the route, the INS measures precise relative movement between acoustic interrogations.
4. As the vehicle moves relative to the beacon, the error ellipse progressively improves on multiple axes, gradually resulting in a more accurate position.

Following this principle, each range measurement helps in computing a new position, as opposed to classical triangulation algorithms, for which at least three simultaneous range measurements are required to establish a position. It is therefore possible to navigate with fewer transponders without making any compromise on performance.

iXblue’s sparse LBL positioning system is based on its Canopus transponder and ROV-mounted Ramses transceiver, and their seamless integration with INS. Canopus offers exceptional power efficiency, which enables it to operate for up to three to four times longer than competitors’ transponders and thus reduces the time (and money) spent swapping out exhausted units. Sparse positioning also means fewer transponders to be deployed and recovered, with associated vessel time savings.

Figure 1

A unique project

In 2019, UTEC had the opportunity to propose a sparse LBL solution for a project following an invitation to tender from a major subsea contractor. The tender specified the need for conventional LBL positioning; however, UTEC also presented a proposal based on a sparse LBL solution, which interested the client, as it had also been evaluating the value of sparse LBL systems for future projects.

iXblue supported UTEC’s sparse LBL proposal and also met with the client to discuss how Canopus and Ramses could unlock time and cost savings on this and future projects. UTEC evaluated competitor sparse LBL positioning solutions and concluded that the iXblue system had clear technical and commercial advantages, including the longer battery life, backed up with proactive support. This combination would achieve the most cost-effective solution for UTEC’s client.

Through a combination of a good technical proposal, an attractive commercial offer and support from iXblue, UTEC was awarded the contract, now based on the use of sparse LBL positioning. There was a clear stipulation from the client: the choice of the sparse LBL system and its use on the project was UTEC’s responsibility. This placed great emphasis on iXblue’s technologies to deliver as promised. Although Canopus and Ramses LBL systems had been presented to the industry during trials and demonstrations and used on a North Sea rig move in 2018, neither had been deployed on an actual commercial project within the energy industry, and UTEC would be the first user of the system.

This presented significant risks for both iXblue and UTEC: failure of the system to deliver would result in delays and extra costs for the client, while UTEC would also incur replacement costs and suffer reputational damage and thus potential loss of future work. Equally, failure could damage the reputation of iXblue’s new LBL technology such that it could lose market trust.

Risk assessment and management

Project failure was never an option. Working together, UTEC and iXblue surveyors, engineers and senior management sat down and, in a risk assessment process, identified four key risks that could negatively impact the project: manufacturing delays, the absence of necessary system capabilities, a lack of adequately trained personnel, and design or manufacturing faults leading to system failures.

Manufacturing constraints

UTEC was concerned that iXblue would be unable to manufacture the required number of Canopus and Ramses units in time for the project start date. Consequently, a delivery date was imposed so that, if missed, there was sufficient time to change to an alternative supplier and redesign aspects of the project. Despite impacts from the COVID-19 pandemic, the required number of units were successfully delivered by the iXblue teams on schedule.

System capabilities

Both UTEC and iXblue had concerns that the Canopus and Ramses systems could not perform some of the complex positioning tasks required by the project. UTEC surveyors listed the necessary positioning tasks for comparison with the capabilities of the system and identified the missing capabilities, all of which were already on iXblue’s development roadmap. Consequently, iXblue prioritised their development and implementation. The new capabilities were successfully proved in tests offshore iXblue’s La Ciotat base in the South of France. UTEC personnel were unable to attend in person owing to COVID travel restrictions but successfully witnessed the tests arranged by iXblue via remote access to the positioning computers and live video streaming from the test vessel.

Trained personnel

As this was the first time that the Canopus and Ramses systems were being deployed, UTEC field personnel needed training in how to operate the systems. Lockdown and travel restrictions due to the pandemic presented a major challenge, resulting in training having to be done remotely.

iXblue designed a programme consisting of two training sessions, feedback from which identified changes necessary for easier operation. For instance, field staff felt that the user interface for the system was inefficient. They provided a list of improvements that were subsequently implemented by iXblue’s software developers. The improvements were then successfully tested by some of the field staff operating the software on iXblue’s test vessel via a remote-control link.

Further actions included the deployment of an iXblue engineer on the installation vessel to oversee the initial stages of the programme. Additionally, a satcom link was established between onshore iXblue specialists and the actual Ramses units fitted to the ROVs. This enabled the onshore support team to configure and operate the system directly should the offshore personnel encounter problems. Although the link was not required, it was proved operational and thus provides an option for reducing the number of offshore personnel needed on future projects.

Reliability

When deploying new systems for the first time, there is always the potential for reliability issues. UTEC and iXblue considered the consequences of multiple failures caused by design or manufacturing faults and implemented several measures to minimise the risk of potential failures; these included ensuring that more spare units than normal were on the vessel.

More importantly, iXblue’s design and manufacturing procedures were audited by UTEC using a process more rigorous than that typically used for audits of routinely used equipment. Again, these audits had to be carried out remotely; however, iXblue’s electronic quality assurance and control systems enabled the audits to run smoothly and provided assurance of system reliability.

Project outcome

By undertaking a detailed risk assessment and implementing mitigation measures, UTEC was able to successfully deploy the Canopus and Ramses positioning system on the project. And the system performed excellently: predicted time and cost savings were achieved, and a wealth of experience, to be used on future projects, was gained by all parties.

“Both UTEC and iXblue had to commit the people and time to ensure a successful first-use of Canopus and Ramses. We now have the knowledge and experience that enable us to offer this system for other projects. The risk assessment process will be applied to future first uses of new systems. We anticipate that this will enable us to provide additional cost-saving solutions for our customers,” comments Paul Smith, Group Managing Director at UTEC.

Olivier Cervantes, VP Energy Market at iXblue, concurs.  “I agree with Paul and add that I was impressed by the commitment of the UTEC teams in the quality audit of our system and how they have challenged our technical teams. Converting risk taking into value creation through a careful assessment of potential issues was one of the challenge, all of this during an historical global pandemic. Spirit of teamwork, trust and the willingness towards an improved solution, allowed us to push the limits of the technologies, bringing an “open architecture” Sparse LBL to the market standard.”