HE REFUSES to work when cold, can move only one arm at a time – and, at £100 million, his services don't come cheap.
But with 11ft arms, hands the size of microwave ovens and a formidable tool pouch at his hip, Dextre is the first robotic handyman in orbit.
Going where no android has gone before, the gangly robot – nicknamed C-3PO's great- grandfather – yesterd
ay became the newest crew member aboard the International Space Station, where it will perform heavy construction and maintenance tasks considered dangerous or difficult for its human colleagues.
Dextre – or special-purpose dexterous manipulator – was flown to the ISS aboard the space shuttle Endeavour in nine pieces and assembled during a risky eight-hour spacewalk 220 miles above the Earth.
Astronauts described the robot's rising from its transport crate as being "like Frankenstein's monster coming alive", while its developers at the Canadian Space Agency (CSA), which works in co-operation with Nasa, likened it to the fictitious android heroes of the 1977 film Star Wars.
"I see this as the great-grandparent of robots like R2-D2 and C-3PO. It's an operational robot that's pushing the limits of what we can do in space today," said Daniel Rey, manager of the Dextre project for the CSA.
The astronauts Richard Linnehan and Michael Foreman, both 50, put together Dextre – pronounced Dexter – while floating outside the ISS as it orbited Earth at 17,500 mph.
"It is really eerie out here. It's pitch black and there is just this big, white kind of humanoid-looking thing below me," Mr Linnehan told mission controllers in Houston over the radio.
Standing 12ft tall and weighing 1.5 tons, Dextre has a human-looking torso that swivels at the waist, arms with seven joints and hands with retractable claws that can grip tools and objects from the size of a telephone directory to a telephone box.
As Nasa and its international partners hurry to complete construction of the ISS by 2010, Dextre will be used to carry out external jobs that could otherwise be fulfilled only by sending astronauts on punishing spacewalks.
It is operated by human commands and has dexterity and sensory abilities far superior to those of spacewalking astronauts, whose bulky spacesuits and thick gloves make precision tasks tricky.
The robot can move up and down, left and right and can tilt, pitch, yaw and even open compartment doors to rummage in its own toolbox, remove what it needs and use it to perform DIY jobs.
"Dextre is unique in that it's able to remove and replace items on the space station rather than just move them around," said Michel Wander, a CSA engineer. "It can unbolt a computer or a camera or a component that has failed and replace it."
Dextre will live on the end of the Canadarm, from where it will have a bird's eye view of Earth. It has four "eyes" in the form of sophisticated video cameras that feed images to astronauts inside the station, allowing them to monitor its performance, and lights so that it can work in the dark.
To guard against a robotic mutiny, Nasa officials have laid down a code of conduct to keep Dextre in check and prevent it from running amok.
"Dextre may not injure a human being or, through inaction, allow a human being to come to harm," they stated in an e-mail to Endeavour's crew, paraphrasing science-fiction writer Isaac Asimov's three laws of robotics.
"Dextre must obey orders given to it by human beings, except where such orders would conflict with the first law. Dextre must protect its own existence as long as that does not conflict with the first or second law."
Garrett Reisman, another of Endeavour's seven crew, said of Dextre: "I wouldn't say we're worried it's going to run amok and take over the space station, or turn evil or anything, because we all know how it's operated and it doesn't have a lot of its own intelligence.
"But he's enormous and to see him with his giant arms is a little scary; it's a little monstrous."
But Dextre's sophistication was lost on one Nasa staffer involved in assembling the robot. As the android was powered up and raised into position, the human was heard to observe over the radio that it "kind of looks like a scarecrow".
HOW THE CREW GOT 'MEDIEVAL ON MR DEXTRE'THE already challenging outing to get Dextre up and running ended up using brute force rather than hi-tech to resolve a problem, as spacewalkers Richard Linnehan and Michael Foreman struggled to release one of the robot's arms from the transport bed where it had been latched for launch.
Two of the bolts wouldn't budge, even when the astronauts banged on them and yanked as hard as they could. They had to use a crow bar to get the arm out. "We're really having to get medieval on Mr Dextre," said Foreman.
The other arm came out much more smoothly and quickly, paving the way for Linnehan to pull up Dextre's body 60 degrees. That was the ideal position for plugging Dextre's gangly arms into its shoulders.
"The whole team did a spectacular job today," Mission Control radioed the crew after the spacewalk. "You guys ought to be proud of yourselves."
Zebulon Scoville, the lead spacewalk officer for Endeavour's mission, said the ground team was ecstatic when Linnehan and Foreman got the last bolt out. "The crew performed beyond what could ever be expected of them," Scoville said.
The full article contains 930 words and appears in The Scotsman newspaper.
