Robot fish to catch pollution

By Fiona Harvey in London
Published: March 20 2009 02:00 Last updated: March 20 2009 02:00

The sea of northern Spain is shortly to be invaded - by robots.
Scientists are building a shoal of robot fish to be let loose in the port of Gijon to check on the quality of the water.

Modelled on carp and costing about £20,000 ($29,000) each to make, the fish are to be lifelike in appearance and swimming behaviour so that they will not alarm their fellow marine inhabitants.

The robots, the first of their kind, are equipped with tiny chemical sensors capable of detecting pollutants in the water.

These let the fish home in on the sources of hazardous pollutants, such as leaks from vessels or undersea pipelines.

The fish were developed by the University of Essex in Britain and BMT Group, a UK-based engineering consultancy.

They are the result of a three-year research project funded by the European Commission.
"Using shoals of robotic fish for pollution detection in harbours might appear like something straight out of science fiction [but] there are very practical reasons for choosing this form," said Rory Doyle, senior research scientist at BMT.

"In using robotic fish we are building on a design created by hundreds of millions of years' worth of evolution which is incredibly energy efficient.

"This efficiency is something we need to ensure that our pollution detection sensors can navigate in the underwater environment for hours on end."

Each robotic fish is about 1.5 metres (5ft) long and can swim at a maximum speed of about one metre per second. Whenever they find traces of pollutants, the fish can relay the information to the shore.

The robots are autonomous, rather than remote-controlled, and run on batteries that are recharged every eight hours or so when the fish return automatically to a charging point. The final touches are still being made to the design of the fish, which are scheduled to be released into the port's waters next year.

Professor Huosheng Hu of Essex university said: "[The fish] will be able to detect changes in environmental conditions in the port and pick up on early signs of pollution spreading, for example by locating a small leak in a vessel. The hope is that this will prevent potentially hazardous discharges at sea, as the leak would undoubtedly get worse over time if not located."
http://www.ft.com/cms/s/0/0b63f9f4-14ef-11de-8cd1-0000779fd2ac.html