NASA Wants to Build Robotic Pit Stops for Satellites

NASA has a big satellite problem: The damned things keep breaking. This is to be expected, in a way. Satellites are giant machines made up of machine parts — nuts, bolts, what have you — that float in space miles above the surface of the Earth. They need fuel to power their propulsion units that keep them in orbit. Sometimes they get hit by stuff. And every time something like this happens to a satellite in orbit, the space agency has to load a bunch of astronauts up on a rocket ship and send them up to fix it. This gets expensive, which is probably why NASA is developing a robotic service station to hang out in space and fix the satellites when they zoom by.

Engineers on the ground at the Kennedy Space Center and the Goddard Space Flight Center are working hard on building these satellite servicing satellites. For now, the tools are being perfected as part of the Robotic Refueling Mission (RRM) on the International Space Station. NASA delivered the RRM on the Atlantis space shuttle’s final mission in July 2011, and it’s been up there ever since testing out its repair techniques. The RRM is about the size of a washing machine and weighs 550 pounds. On the ISS, it’s been working with the Canadian built Special Purpose Dexterous Manipulator, a.k.a. Dextre, which serves as the space station’s robotic handyman.

The machine’s capabilities sound pretty simple for now. “The four RRM tools cut and manipulate wires, unscrew caps, open and close valves and transfer fluid demonstrating that a remote-controlled robot can service and refuel a satellite in orbit,” explains the space blog SEN. “In March 2012, Dextre performed the most intricate operation ever attempted by a space robot, cutting two twisted wires each only 0.5mm in diameter using the RRM Wire Cutter Tool.”

The real challenge comes later this year, when the RRM has to pull off its first on-orbit refueling mission. What’s simple for gas station attendants is made unreasonably complex by the challenges of space and, well, getting a robot to do all the work. To pull this mission off, the RRM will have to use all its tools to move and cut wires, unscrew the gas cap and connect a refueling hose and eventually transfer liquid ethanol into the satellite. Then, of course, it has to put everything back in order and send the satellite on its jolly way. Again, sounds simple here on Earth. Much harder up in space.