Researchers Wave Bye Bye to Dangerous Offshore Maintenance with New Wave-Predicting Robots

Researchers from the University of Edinburgh and the National Robotarium are working towards giving autonomous sub-sea robots the ability to better predict, and counteract, wave patterns to reduce the cost of off-shore renewable energy projects.

"A major limitation at present is robots’ ability to perceive and counteract environmental disturbances effectively, which fundamentally restricts the current use of small sub-sea vehicles," explains Kyle Walker, first author on the paper that resulted from his PhD work. "By forming a prediction of future wave disturbances and integrating this within the control system, we're able to expand this range with little to no change to the robot hardware. In terms of translating this technology into the field, this is a huge benefit and makes our system applicable to most vehicles currently available on the market."

Offshore renewable projects require upkeep, inspection, and maintenance, in often turbulent conditions. For humans, there's real risk involved; for autonomous robotic systems, issues with the unpredictability of the conditions. Taken together, the problems account for a big chunk of the cost involved in offshore energy harvesting — which Walker and colleagues aim to solve, by using new tools to enable undersea robots to better predict and counteract wave patterns.

The team's work, tested in a wave tank reproducing conditions recorded by a North Sea buoy, uses sensors tethered to the sea floor to measure the direction and height of incoming waves. This data is fed in real-time to undersea robots, which process it in order to better predict upcoming disturbances — and to work against them, so the robot remains firmly positioned wherever it is required.

Initially, the researchers are concentrating on proving that the robots can hold themselves steady against the conditions you'd expect to find in real-world offshore environments. The next step: extending the system so the robots can not only remain stable but carry out complex work, required to maintain offshore energy harvesting equipment, at the same time.

"Increasing the use of autonomous robots to help maintain offshore renewable installations could have a transformative effect on cutting the cost of producing clean energy," says Francesco Giorgio-Serchi, project lead, of the work's potential. "Advancing this technology further could help bring about a step change in the adoption of unmanned robots at sea and drastically increase the degree of automation in the offshore sector."

The team's work has been published in The International Journal of Robotics Research under open-access terms.