On space station, droids get a workout
'Smart' orbs, now being tested on the space station, may become NASA's worker bees in space.
Cue the John Williams theme and roll the vanishing intro – Obi-Wan Kenobi's Jedi-training droids have arrived on the International Space Station (ISS).
Or at least David Miller's versions have arrived. The free-floating spheres are set to test new concepts for "smart" satellites. Able to fly in precision formation, the robots may one day hold the key to building everything from huge space telescopes that can peer deeply into the universe to constellations of small, cheap satellites that can monitor changes on Earth.
The shuttle Discovery last week brought the second of three droids that are undergoing experiments as they arrive.
If the experiment, dubbed SPHERES, sounds like science fiction, perhaps that's because it was inspired in part by it. While working on formation "flying" for satellites, Dr. Miller, director of MIT's Space Systems Laboratory, challenged his students to build prototypes.
"I rented the first 'Star Wars' movie and showed the class the scene where Luke is practicing the use of the Force with a floating droid," he explains. "I said: 'I want three of those. How do we start doing this?' "
The result: spheres the size of bowling balls crammed with computers, position sensors, and tiny thrusters made to maneuver with precision.
After years of testing – including trials aboard a NASA jet whose flight path allows occupants a brief experience of weightlessness – the first of three spheres arrived in April aboard a Russian Soyuz spacecraft. A second arrived with Discovery, currently docked at the International Space Station, and the third is slated to arrive on Discovery in December.
Each orb weighs nearly nine pounds. Twelve thrusters use gentle puffs of carbon dioxide to change the orb's orientation and location. Each orb can figure out where it is by using 24 tiny microphones to listen for chirps from pager-size ultrasonic beacons placed on the station's walls.