Visualisation, simulation and control in subsea operations
Recovering offshore oil and gas reserves in water depths as great as 6,000 feet presents huge challenges for operators in the installation, inspection and maintenance of equipment on the seabed. These can only be addressed by the use of autonomous and remotely controlled equipment and techniques. Increasingly, visualisation, simulation and control technologies are playing a key role in the remote operation of subsea and ocean floor equipment.
Fugro General Robotics Limited (FGRL) based in Milton Keynes, UK, is a highly experienced provider of subsea visualisation and simulation systems. FGRL’s core product is DeepWorks which uniquely is available in different configurations to provide an ROV trainer, an engineering simulator and a live operations visualisation tool.
The DeepWorks ROV pilot training simulator uses dynamic simulation, with hydraulic and electrical component libraries to reproduce the actual subsea conditions and ROV tooling that define the physical environment in which ROV pilots must work. DeepWorks brings fully force-modelled physics simulation to subsea and ROV simulators, so that any object in the world model feels and behaves like the real thing. It provides “touch and feel” interactive simulation so the simulator pilot gets the same tactile response as if he were actually using a tool to move or adjust a subsea component in the field. DeepWorks also interconnects with cables, tethers, vessels and other real world items all of which can be controlled, driven, and winched in realistic fashion. Different visibility conditions can be simulated, with varying light levels, water fogging and suspended particles together with realistic sonar data. The resulting information is truly 3D and allows immersive documentation, live data recording, training and marketing material to be built on real physics-based outcomes.
For planning purposes, running DeepWorks Engineer on your PC desktop provides a sophisticated dynamic simulation engine which models the true hydrodynamic responses of offshore equipment when acted upon by environmental conditions. An engineer can quickly drag and drop components from the extensive libraries to build subsea scenarios containing items like vessels, pipes, cables and ROVs. The engineer can also add his own custom components by importing 3D engineering models and defining key properties.
By adding Fugro GRL’s real-time monitoring library to DeepWorks Engineer, full situational monitoring of topside and subsea mobile assets during complex offshore missions is achieved. DeepWorks Engineer Live takes input from live systems including Fugro Starfix, and NMEA Standard inputs such as GPS, Gyro and USBL data. A live 3D World View enables both management and offshore teams to react more quickly to operational developments giving a clear and accurate picture of what is really happening subsea. Teams can combine live data such as vessel location with simulated data like pipeline location during a pipe-lay. As the operation unfolds the full situation is recorded in the 3D world for subsequent review.
Norway's SimSea AS has ordered a DeepWorks ROV simulator, integrated to run synchronously with a Kongsberg offshore vessel simulator to provide a seamless operations training platform for the launch, recovery and operation of an ROV. This will be delivered in Q4.
DeepWorks can also speed up the evaluation of subsea engineering designs by modelling complex subsea machinery in great detail. This simulation makes it much simpler to evaluate and change ROV and tool designs prior to manufacture and reduces reliance on expensive and time consuming prototypes. Full hydraulic and electrical circuit modelling combined with a suite of actuators and manipulators, means virtually any ROV or tool can be created. This has direct application to training, field engineering and cost-effective product development.
Fugro Subsea Services Ltd in Aberdeen makes extensive use of DeepWorks for the rapid evaluation of subsea engineering tools and designs, and for the effective planning and validation of new tool operating procedures. This includes training the pilot to perform the newly engineered mission before deployment. Fugro Subsea Services Ltd bought DeepWorks due to its ease of use, specifically because a subsea engineer can quickly customise it for a particular task whereas competitor systems require a programmer to make the changes. This allows Fugro Subsea Services Ltd to use DeepWorks to deal rapidly with unexpected issues as they arise. If during a site inspection for a client, equipment failures are detected – possibly threatening production - then DeepWorks allows more rapid prototyping and proving of tools to fix the problem.
For ROV pilot training the underlying ROV systems are fully modelled, which allows supervisors to temporarily “break” individual circuits or components to test how well pilots understand their equipment. Introducing such failures enables trainees to learn the necessary remedial actions and to recognise the circumstances in which missions can be completed safely, albeit more slowly, when the ROV systems are compromised or a worsening sea state is encountered. Trainees can easily repeat a scenario until they get it right. All of their different mission tracks are recorded and can be returned to at any point for review.
Rapid Prototyping of Subsea Tools
Monitoring structural integrity on offshore platforms can be time consuming, expensive and potentially hazardous if divers are employed. Fugro GRL has assisted in the development of a ROV deployable underwater tool for non-destructive testing of subsea structures.
TWI in Cambridge has developed a prototype Long Range Ultrasonic Tool (LRUT) designed to be deployed by ROV and clamp around vertical or horizontal jacket tubulars. Fugro GRL created a simulation of the deployment of the tool by ROV and a simulation of the tool’s operation in attaching itself to the tubular. Carrying out a simulation of the tool’s operation was useful in reducing risk and cost prior to the underwater trial, in providing an early learning opportunity for engineers, and to allow design changes to be made based on the simulation rather than waiting to discover problems in the trials phase. The simulation has provided important proof of concept for the application of this tool.
Using DeepWorks, FGRL was able to model the articulated mechanism of the ultrasonic manipulator as well as its electro-hydraulic supply system from the ROV. The tool can be tilted up and down, rotated and clamped around vertical and horizontal tubulars. The LRUT model was quickly generated using CAD models supplied by TWI. DeepWorks’ simple drag and drop user interface allowed the model to be rapidly configured and early simulations were possible within a day. Refactoring and modifications were easily carried out by engineers without the need for any programming skills.
“Sea trials are among the most expensive aspects of subsea product development, and here simulation can play an important part in keeping costs down by reducing the amount of live testing that is needed,” said Dr Jason Tisdall, Managing Director of Fugro GRL. “FGRL was happy to work with the TWI consortium, cooperation in which we both broadened our expertise.”
FGRL’s customers frequently come up with new applications’ requirements, sometimes at very short notice. Successful product development requires a stable but flexible platform and the ability to adapt quickly to changing needs. DeepWorks has been developed on the latest C# .NET platform, and uses state-of-the-art automated workflow tools to enable new features to be incorporated quickly whilst ensuring quality through tight build and release control. A typical example was when a customer required a new input device to drive a simulation from a midi controller in which a bank of eight sliders could be used to drive the winch controls on lift lines and umbilicals simultaneously. In this instance, a beta copy of the software was released in only four days with the final release code delivered, following extended testing, in just three weeks.
From proof of concept through to project review and documentation, DeepWorks provides an integrated suite of tools to help subsea operators complete each project task efficiently and effectively. Simulation and control technologies now give operators an unprecedented insight and ability to intervene directly in the design, development, deployment, operation and maintenance of subsea and seabed equipment, thus minimising risk and speeding up the production process.