NASA's space robot assembled, awaiting first assignment
- — 18 March, 2008 18:36
With power flowing and arms, cameras and even a tool belt in place, NASA's space robot is ready for work.
Tuesday night's space walk was the last one needed to get Dextre up and running. Now, the 12-foot-tall robot with a 30-foot wing span will undergo a series of tests to make sure it's in full working order -- and wait for its first assignment.
"It's great to have it up there," Beutel told Computerworld. "No matter how much you test on the ground, you're going to have hiccups and you have to deal with it in space. We're learning how to work and build stuff in space. This is what we need to learn."
The robot is expected to take on most of the maintenance jobs required outside of the space station, thus cutting back on the number of dangerous space walks the astronauts must make. Dextre can work with objects as large as a phone booth or as small as a phone book.
A challenge for the engineers on the space station and on the ground is that the robot went into space in nine different pieces. It never was fully assembled on Earth as it would have been crushed by its own weight - 3,400 pounds. The first time it would be in one piece and operated as a whole, would be orbiting at 15,700 miles per hour, 220 miles above the Earth.
In the space walk Monday night, two astronauts attached a foot-square camera on a three-foot rigger extending out from Dextre's hip. The camera will be one of five that eventually will be set up - one on its foot, one on each gripper and two on its hips - to give Dextre and its operators a "stereo view" of what the robot is working on.
Michel Wander, a systems engineer who worked on Dextre at the Canadian Space Agency, said astronauts also attached a tool holder assembly to Dextre Monday night. The attachment, set up much like a tool belt, holds tools, like a socket extension and a robotic microconical, that Dextre will need to do maintenance work on the outside of the International Space Station.
The astronauts also attached a platform that will hold spare parts, so when Dextre moves to a worksite, it can carry the parts it needs with it.
"Right now, because both arms are attached, he looks pretty gangly and humanoid," said Wander. "After Monday night, if they need him, they could use him. But that's not planned. He still needs some testing."
Wander pointed out that Dextre already has undergone its first round of testing, with engineers checking each of the robot's 15 joints to see if they are moving properly or if there's too much slippage. He noted that all the joints tested within acceptable parameters but one joint was close to the limit in terms of slippage. After working with it and re-running the test a few times, all was well.
Beutel noted that the crew of the space shuttle Endeavour, which lifted off last week for a 16-day mission, has already performed more space walks in one mission than any other crew. So far, they've done five space walks, which have involved assembling Dextre, as well as attaching the new Japanese lab to the space station.
"If we have any chance of pushing out into the universe, starting with our own solar system, we have to learn how to live in space," said Beutel. "We're taking baby steps to here to do that."