Introducing the AusOcean "rig"



You might often hear us talk about our monitoring "rigs"; we've coined this term to describe our sea-surface platforms. You may have seen one, but do you know what they do? Well, read on.

The AusOcean "rig" is a low-cost sea surface platform for supporting ocean science in coastal waters. Despite their relatively small size, rigs have been successfully deployed in South Australian coastal waters for many months at a time, proving to be very reliable against harsh oceanic conditions. Our toughest deployment location to date is Smith Bay on the north coast of Kangaroo Island where seas can reach 5m!

Rigs have been strategically designed to meet the following requirements:

  • Low cost
  • Stability
  • Seaworthiness
  • Maritime safety
  • Flexible support for multiple sensors

The rig is a custom pontoon design in a light-weight modular construction. The pontoons, braced by steel crossbars, provide a stable and buoyant platform, similar to the bridge deck of a catamaran. Two solar panels span each side of this platform to provide battery charging. Projecting vertically from the platform is a high visibility tube, known as the mast, housing system electronics. Both the pontoons and the mast are built from low-cost, durable stormwater-grade PVC, and the frame is made from metal (galvanized steel and aluminium). The rig's batteries are located in a water-proof compartment just above sea level, contributing to the rig's low centre of gravity and stability. The rig is further stabilized by a bridle system connected to subsurface bar (the "bridle bar") and a weight suspended below the bar (the "centre weight"). In addition to providing the function of a keel, this system maintains mooring line tension. The pontoons, mast and batteries can be easily disassembled and reassembled.


Traditional, vertically-oriented "pear-shaped" buoys with heavy keels (to provide ballast), provide either limited space and/or poor orientation for solar panels. In contrast, the rig's design affords the maximum horizontal surface area for its size, in turn maximizing the capacity of the rig's solar panels.

The rig's electrical system is either 12V or 24V DC (configurable). Power is generated by two 40W solar panels, and energy is stored in two 14Ah 12V batteries, providing 336Wh of energy (28Ah). Each rig has an ESP8266 microcontroller which performs mission-critical functions, such as the navigation light, battery monitoring and power management.

Rigs are connected to the Internet, and therefore form part of the so-called Internet of Things (IoT). By virtue of being connected, rigs are remotely manageable via AusOcean's cloud service. This allows us to remotely monitor rig functions such as battery voltage, sea surface temperature (SST) and humidity. This data is transmitted straight to the “cloud”, where it is stored, shared and analysed in real-time. Real-time application aids in our ability to effectively detect and respond to any potential failures, and trust us, there are many! The ocean can be a harsh environment to work in.

We are constantly looking at novel ways to tackle ocean science and conservation challenges. A top priority of ours is continuous underwater video. Unlike BRUVS (Baited Remote Underwater Video) these cameras are designed to be deployed for months at a time collecting valuable data on natural species compositions. Video can also help us monitor important environmental parameters such as turbidity - the cloudiness or haziness in the water due to particle suspension. Unlike most consumer video cameras ours are designed for continuous streaming of video data up to depths of 20m. By using passive Power over Ethernet (PoE), we combine a 24V DC power supply with data over a single Cat 6 waterproof cable. This provides both power and network so we can live-stream collected footage.

Our goal is to transform the way in which ocean data is collected and communicated, a belief central to our operations is the development of open-source technologies. Open source approaches to tackling environmental issues means embracing collaborative tools and workflows which enables processes and progress to be fully transparent. By contributing to, and supporting open source practices, we hope to accelerate research and encourage transparency.

Rigs are built by students as part of our student-led citizen science program Network Blue. For more project info head to https://www.ausocean.org/projects/networkblue.

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