HOUSTON – Spacewalking astronauts added hands to a robot outside the international space station early Friday as experts on the ground devised a plan they hope will fix a problem getting power to the giant machine.
The Canadian robot, named Dextre, needs to have power to heat its joints, limbs and electronics. The $200 million machine designed to help maintain the orbiting outpost could be damaged if left cold for days.
Canadian engineers initially suspected the trouble could be with a timer, and they created the software patch to fix it.
But Pierre Jean, Canada's acting space-station-program manager, said experts now believe the problem stems from a design flaw in the temporary cable that is supposed to provide power to Dextre until it is fully assembled.
If that's the case, Jean said, Dextre should have no trouble powering up once the astronauts finish putting it together and install it on the station next week.
To be sure, the crew plans to hook up Dextre to the space station's robotic arm later Friday.
If the problem is with the temporary cables, Dextre should receive power from the arm. If it doesn't, engineers will have to find another fix.
"I think at this point in time we're pretty confident that by 10 o'clock tonight we should have the answer to this particular question," Jean said.
In the worst case, spacewalking astronauts could go back out to disassemble Dextre and leave it in pieces at the space station. That way, the robot would not have to be heated.
The crew still ran the software patch to see if it helped, but it didn't.
While spacewalkers Richard Linnehan and Garrett Reisman worked on the robot, two of their crewmates used a robotic arm to remove a Japanese storage compartment from shuttle Endeavour's cargo bay and attach it to the space station.
It's the first part of Japan's massive Kibo lab, which means "hope." Shuttle Discovery is scheduled to deliver the main part of the lab in May.
The spacewalk, which lasted seven hours, was the first of five planned during Endeavour's unusually long stay at the space station. Three of them will focus on Dextre, one of the Canadian Space Agency's main contributions to the space station.
The 3,400-pound robot, when assembled, is 12 feet high and has a shoulder span of nearly 8 feet. It's designed to help spacewalkers with some of their more routine maintenance chores, with the eventual goal of reducing the amount of time astronauts spend outside.
It was the first spacewalk for Reisman, who flew up on Endeavour and will live aboard the station until June. It was the fourth spacewalk for Linnehan, who worked on the Hubble Space Telescope in 2002.
Toward the end of their outing, the spacewalkers were treated to a stunning view of city lights in the midwestern United States, probably Chicago.
"Oh, wow. Wow. Wow. Wow," Linnehan said. "It's a pretty amazing view."