Newcastle University engineers have developed a robotic cleaning system able to navigate its own way across a ship’s hull and remove marine growths. It offers an effective replacement to environmentally-damaging biocides
The self-navigating robot cleaner makes it possible to improve maritime fuel consumption, while also reducing the environmental impact of previous cleaning approaches. It is a result of the HISMAR project, funded under the EU Sixth Framework Programme (FP6), which set out to develop a multi-purpose inspection and maintenance platform for ships’ hulls with an advanced navigation system.
The innovative system first maps the hull of a ship automatically, recording the locations of every weld, rivet and indent, as well as areas of differing thickness. Once attached magnetically to the hull, it can then use this collected data to plan a route across the surface, cleaning as it travels.
Cleaning is carried out using adjustable jets of sea water. By blasting sea water against the hull, various particles of marine growth are removed efficiently. Once the particles have been separated from the hull they are sucked inside the robotic unit, and processed inside its main chamber. In total the unit processes 150 litres of water a minute, filtering the marine growth particles to remove bio-fouling elements. In doing so, particles that may have previously impacted on the local marine environment are rendered harmless.
Once in use, the robot can continuously patrol the hull, preventing marine growth or slime from ever building up. The robot is intended for use in port and is relaunched at each stop. This regular cleaning enables ships to travel more efficiently through the water, dramatically reducing drag and lessening the amount of fuel consumed.
In addition, the robotic system also offers a far more environmentally friendly cleaning method. Until recently, ships were regularly treated with anti-fouling paints that contained tributyltin (TBT) as an added biocide to prevent marine growth from forming. This substance has now been banned worldwide as it contaminates water surrounding the vessel. This robotic system offers a green alternative as it does not have the same detrimental impact on marine life and the environment.
The HISMAR project: http://www.hismar.eu/
‘Robot cleaners go to hull’ (The Engineer on-line):
Photo: Courtesy of HISMAR