Much attention has been paid to a Canadian milestone in space as astronauts Julie Payette and Bob Thirsk became the first two Canadians to ever orbit the earth at the same time. But while Canada’s humans are grabbing the headlines, its robots are doing the heavy lifting.
After five days of carrying astronauts, lifting massive pieces of equipment and “walking” up and down the spine of the International Space Station, NASA says its robots are performing perfectly in its most technically complicated mission yet.
The seven-person crew of the space shuttle Endeavour, including Payette, are docked and working with the crew of the space station to install the final pieces of the Japanese laboratory on the orbiter. The work, which began on Saturday, simply couldn’t be done without robotic arms – one on the Endeavour and two on the space station – doing all the heavy lifting, said Michael Curie, a spokesman for NASA.
“It’s very exciting to see all the robotic equipment perform to the expectations that we’ve all had,” Curie told Computerworld. “It’s wonderful when you get everyone together in space after a year or two of training, and everything they’ve practiced using robotics is working just as planned. It’s amazing to watch it all working against the beautiful blue background of the Earth.”
Holly Ridings, lead space station flight director for the Endeavour mission, said in a previous interview that this is one of the most technical ever undertaken by NASA.
The robotic arm on the space station, dubbed Canadarm II, and the robotic arm on Endeavour have been working steadily since this past Saturday when they worked hand-in-hand to unload and maneuver the final part of the Japanese Kibo lab into place.
The arm on the station lifted a 4-ton piece of the Japanese complex out of the shuttle’s payload bay. This piece, which has been dubbed a “front porch”, will be permanently attached to the outside of the Japanese module. It is designed to hold its own payloads, as well as host experiments that need to be conducted in outer space.
Once the station’s robotic arm, called the big arm, extracted the porch from the shuttle, it handed off to the space shuttle’s own robotic arm. While the shuttle’s arm held the porch, the station’s arm moved itself about 50 feet down the length of the space station by basically moving much like a child’s Slinky toy.
Either end of the big arm can be used as the base, just as either end can be used as a gripping hand. Once the arm handed off the porch, its gripper end swung over and attached to the space station and the end that was originally attached to the station let go and freed itself to be used as the gripping hand.
At that point, the big arm reached out and took back the porch and moved it into place against the Japanese module where it automatically attached itself.
“It’s fabulous,” said Curie. “When you consider how large and massive these objects are and how easy the robotic arms make it look, it’s astounding. We’re doing things today that weren’t even imagined in 1981 when the shuttle program first flew.”
Since then the two arms have been used to lift a massive cargo carrier out of the space shuttle and moved it to an area where the astronauts could reach it.
The carrier holds equipment on its two sides. On one side a spare antennae for the station was attached, along with a spare pump for a cooling system and a motor that runs along the backbone of the station like a train on a rail. The other side of the carrier held six batteries, which are designed to hold power drawn out of the station’s solar arrays. The batteries are being installed today.
With the cargo carrier out of the space shuttle, on Monday an astronaut attached himself to the end of the big arm and while he grabbed hold of a spare part, the big arm slowly and gently moved him to where the parts needed to be stowed. Taking each spare one at a time, the astronaut made three separate trips on the robotic arm over the course of five hours in space.
“It moved him slowly and methodically because of the size of the spares and the close proximity of the other pieces of the space station,” said Curie. “It would not have been feasible for a spacewalker to have carried these objects from one place to another without the robotic arm. It made what would have taken three space walks possible to do in one.”
Curie added that this kind of work — where a human is attached to a robot 220 miles above the Earth’s surface – takes a lot of confidence in the machine
“It’s not only a trust in the robotic arms but in the crew members who are using them,” he noted. “The [astronauts] practice as a team for over a year to make sure they understand what is required. It looks easy because they’re very proficient at it and because the hardware is very trustworthy.”
On Thursday, the new robotic arm on the Japanese laboratory will be taken out for its first official spin. It’s been tested but this week it will be used in a real operation for the first time. This third arm will be used to set up the new lab and get the experiments into place.
“This is the very first time that three robotic arms have been used on one mission. It won’t be the last, but it will be the first,” said Curie. “I think humans and robotics will be tied together as we move forward in the exploration of space.”
Source: Computerworld.com
