Astronauts move Dextre to new perch
Astronauts shifted the Canadian-built Dextre robot to a new location outside the International Space Station on Tuesday after devoting nearly a week to putting together the two-armed addition to the station.
Dextre — a 3.7-metre-tall robot with 3.3-metre arms — will remain at its new location on the U.S. lab, Destiny, for at least a few months.
Before they could move the robot on the end of the space station's Canadarm 2, astronauts aboard the linked shuttle Endeavour and space station had to fold up its arms. It was a slow process that took an hour for each seven-joint arm.
When the robot finally clamped onto the lab, flight controllers had to take extra steps to resolve a computer software problem. It was not unexpected, and the robot had a solid grip on the lab, said flight director Kwatsi Alibaruho.
Dextre was launched into space in nine pieces aboard a transport bed, or pallet, that served as the robot-construction zone. Three spacewalks were needed to put the robot together. First the hands were attached to the arms. Then the arms were connected to the torso. Finally, on Monday night, the eyes and tool belt were added.
The Canadian Space Agency supplied the $200 million-plus robot, conceived as an assistant to spacewalking astronauts. It may be months, possibly even a year, however, before the robot is put to the test. That's how long it will take to check out the robot and have an appropriate job present itself.
Dextre's initial checkout went well, with just one minor flaw. When the waist joint was commanded to turn in preparation for the robot's relocation, it moved in the opposite direction, Alibaruho said Tuesday night. Engineers believe the problem can be easily remedied via software.
At its new location, Dextre will be out of the way when Japan's massive Kibo lab arrives in May. The first part of Kibo, a storage compartment, flew up on Endeavour.
Astronauts take a break
With their 16-day mission hitting the halfway mark, Endeavour's astronauts finally got some time off. It's the longest planned shuttle flight to the space station ever. The crew will get more free time Wednesday afternoon.
The pace will ramp back up Thursday evening, when two of the crew float outside to test a caulking gun and high-tech goo. NASA wants to see how well the astronauts can fix deliberately damaged shuttle tile samples.
The experiment should have been conducted last year but was bumped because of a more pressing space station problem.
It's one of the many safety measures developed after Columbia was destroyed during re-entry in 2003 because of a gashed wing.
The fifth and final spacewalk of Endeavour's mission — to move the shuttle's thermal-shield inspection boom over to the space station — is set for Saturday night. They'll also try again to hang science experiments to the outside of the European lab, Columbus. Monday night's attempt failed because of some sort of interference.