Super spider prepares to crawl to the rescue

A 10ft robotic spider that can climb walls or carry a 100kg (220lb) person could soon replace rescue workers in hazardous environments such as radiation accidents.

The bright yellow eight-legged robot - named Robug 3 - was designed and built by scientists at Portsmouth University, Hampshire. It is powered by compressed air and has a front-mounted camera, infrared sensor and a laser scanner that can see through smoke-filled rooms.

It was developed to meet the needs of the nuclear industry - where the dangers of sending a human rescuer into a radiation-filled environment might be unjustifiable. Instead, Robug 3, which cost pounds 800,000 to develop in partnership with universities in Germany, Belgium, Denmark and Poland, could go and drag or lift an injured worker.

Gurvinder Singh Virk, professor of control engineering at Portsmouth University, said: "We were asked by the European Commission to build a rescue robot following the Chernobyl disaster. The people in Brussels were really frightened about what could be done if something like that happened again. The idea was to make a machine that could handle anything. It can walk, climb over debris, and even climb up sheer walls when it has to."

The legs have suction pads and each can bear 65kg, so only two legs are needed to support the robot while it is wall-climbing.

Prototypes of Robug are being used by the nuclear industry in Britain, Italy and France, and by the CERN (European Council for Nuclear Research) particle physics project in Switzerland. But the designers also see its potential for industry, mining and the military.

The main problem at the moment is the robot's speed. It can only manage about two yards a minute, because it has to trail a cable to its power source and to the human operator who watches and directs its movements via a television screen.

And the effect on those waiting to be rescued might be unnerving too. Professor Virk admitted that the sight of Robug crawling up a wall can be a shock: "When it's about eight feet above you it really looks frightening," he said.

One of the biggest design problems was making the legs flexible enough for the robot to squeeze through doors, said Dr Bing Luk, who worked on the technical development. Each leg is about a metre long, but can fold into the body.

Robug 3 is likely to be the first of a mechanical family adapted for different jobs which might include maintenance, inspection and safety tasks on ships and in chemical plants, mines and construction. Professor Virk said the scientists were also talking to officials from the Defence Evaluation and Research Agency at the Ministry of Defence.