Shuttle astronauts equipped the 12-foot tall humanoid named DEXTRE with a tool kit, camera and lights. At more than $200 million, the Canadian built machine is designed to assist the spacewalkers. Even with abundant safeguards built into every mission, there is an inherent, unspoken paranoia, which is a good thing to have because it keeps all involved in the space business on their toes.
"It isn't until you hear what they call MECO, which is main engine cutoff that the engines have performed well and the shuttle is successfully in orbit that you kind of breathe a sigh of relief until they get ready to do the de-orbit burn and come back. Then of course, you're holding your breath for another hour or two until the gear hits the runway."
JA Leary, a software engineer with Rocketdyne, spent years designing processing software for the space shuttle. With the safety of those onboard the shuttle at stake, he knows what it's like to be involved with high-pressure projects outside the space craft, where lives hang in the balance.
"One ofthe reasons they have that robot out there...the new one that they're installing is because they want to cut down on the amount of time that the astronauts have to spend outside the station doing this type of work. Because it doesn't take much for an accident to happen and it's not just that. It's the stress that they're under. It's being out there for seven to eight hours at a time. The physicial and emotional strain on them is extreme."
The latest spacewalk require plenty of muscle as one astronaut worked from the tip of the station's 57-foot long robot arm, while another floated next to DEXTRE. Leary says they made it look easy.
"We know from past experience that is a very harsh environment and when you design hardware on the ground, you hope that the engineering parameters that you've designed it under are going to behave once you get it up into space. Sometimes that doesn't always happen, but the one thing that NASA is very good at and has been good at for fifty years is being troubleshooters."
Lear says it's important that engineers and scientists remain pro-active to put shuttle astronauts in the best position to succeed.
"You're not always dealt the best set of cards when you're dealing with environments like this. But, usually NASA and the powers that be are able to pull out a flush most of the time."
More spacewalks are planned for Thursday and Saturday nights.
Pat Hernandez, Houston Public Radio News