Sunday, September 24, 2017


OceanRINGS banner

OceanRINGS is a set of smart technologies for subsea operations developed at the Mobile & Marine Robotics Research Centre (MMRRC), University of Limerick, Ireland. These technologies, developed under the OceanRINGS project, are applicable to the growing international off-shore oil and gas sector, and also for future deployment, monitoring, and maintenance of ocean energy devices. The primary achievement of the OceanRINGS project has been the development of a control and navigation suite for offshore commercial ROVs, far beyond state of the art. This technology helps in reducing shiptime and increases safety, leading to significant saving in ROV operations.

OceanRINGS symbolically represents the dual character of smart technologies:
The Inner and Outer Rings can be rotated/expanded independently of each other, indicating that any module can be transparently interchanged between the Virtual and Real-World Environment.

Specifically, OceanRINGS is a hardware/software and web service platform which enables product demonstration both offline, in a virtual environment (e.g., in a lab or trade show) and online, in real-world (for run-time survey application). This duality of operation opens up new frontiers for the applications of modern control, modelling and simulation tools in marine technology development. It provides a framework for researchers to develop, implement and test advanced control algorithms in a simulated virtual environment under conditions very similar to the real-world environment. Since virtual and real-world components are compatible on a signal level, switching between them is easy and transparent. New control algorithms can be developed in virtual environment and once they work there, they will also work in the field.

Under the OceanRINGS project MMRRC developed an improved user interface with touch screen controls and more intuitive 2D and 3D real-time displays that allow better situation awareness and enable ROV pilots with average skills to achieve exceptional results. The 2D display integrates graphical and numerical displays to provide a real-time visualization of navigation data. On the 3D display, the ROV pilot can see the real-time augmented reality visualisation of ROV in the underwater environment.

2D Real-Time Display
3D Real-Time Display
Pilot Interface

An important feature developed under the OceanRINGS project is a fault-tolerant thruster control system. The control system enables the ROV to be functional even in case of thruster faults. In a fault-free case, the control system uses the thrusters in an optimal way, minimizing the energy consumption. If thruster faults are present, the control system automatically accommodates the faults, keeping full controllability of ROV for low speeds and providing opportunity for safe continuation of a mission in presence of thruster fault(s).

There are five basic control modes: three in the horizontal plane (headings) and two in vertical plane (heaves). For the horizontal plane the heading mode can be "Follow Course", "Independant" and "Fixed Point". In the vertical plane the heave mode can be either "Constant Depth" where the ROV is being kept on the same distance from the sea surface, or "Constant Altitude" where the ROV is following the seabed profile and is keeping the same distance from the seabed. The heading mode describes the heading (direction of the ROV's cameras) of the ROV considering the course on which the ROV is. For the "Follow Course" mode, the heading and the course will be the same all the time, "Independant" mode means that ROV will keep the same heading no matter what the course is and "Fixed Point" mode describes the mode where, according to the course changes the heading changes to keep a selected point in front of the cameras.

Heading Mode: Follow Course
Heading Mode:Independent
Heading Mode: Fixed Point
Heave Mode: Constant Depth
Heave Mode: Constant Altitude