Robo-fish Swarm Unleashed 

 

A smaller version of the robo-fish began swimming around in a special tank at London’s aquarium in 2005, wowing visitors with its lifelike movements and brightly shimmering scales.

A school of autonomous robotic fish will be released into a Spanish port to help monitor pollution. Information gathered from the robo-fish will be transmitted to the port’s control center using a wireless Internet signal when the devices surface, and the data gathered will be used to create a real-time 3-D pollution map of the harbor’s area.

The five-foot-long battery-powered robots work by mimicking the swishing movements of a fish’s tail, according to University of Essex robotics expert Huosheng Hu, whose team is manufacturing the machines. Hu said the robo-fish will be equipped with sensors to monitor oxygen levels in the water and detect oil slicks spilled from ships or contaminants pumped into the water from underground pipes.

The robotic fish will patrol the harbor of Gijon, in northern Spain under a 2.5-million-pound ($3.6 million) grant from the European Union. Hu said Gijon was chosen because port authorities there had expressed an interest in the technology.

The plan might seem “like something straight out of science fiction,” said Rory Doyle, a researcher working on the project, but he explained that there was a very simple reason for choosing fishlike machines to monitor the harbor’s environmental health.

“The design of fish which nature has produced is a very energy-efficient one,” Doyle said. “The fish’s efficiency is created by hundreds of millions of years’ of evolution. Submarines come nowhere near it.”

The robo-fish won’t need remote guidance — their sensors can help them avoid obstacles such as rocks or moving ships, said Doyle, who works for the engineering consultancy BMT Group Ltd., a member of a consortium manufacturing the machines.

They will be designed to adapt quickly to changes in the port environment, with advanced swarm intelligence techniques used to control and coordinate them. The fish can also swap navigational information with each other using a form of sonar. When their batteries are nearing the end of their eight-hour capacity, they can swim back to a power hub to recharge.

Each robo-fish costs about $28,000 to make, and BMT estimates their maximum speed at about one yard per second.

A smaller version of the robo-fish began swimming around in a special tank at London’s aquarium in 2005, wowing visitors with its lifelike movements and brightly shimmering scales. Hu said the new fish will have to be bigger to withstand higher water pressures and powerful Atlantic tides. He also noted that issues such as data security, communication and clean energy will be interesting challenges.

Hu doesn’t yet know precisely what the machines will look like or even what they will be made of, but he acknowledges the bigger fish probably won’t have the charm of their showy, blue-and-silver aquarium-dwelling cousin.

“This project’s more focused on robustness,” Hu said. “Appearance doesn’t have a high priority.”

Hu hopes to release the robo-fish into the water within the next 18 months.

Copyright 2009 The Associated Press.