Which Humanoid Robot Stands Up Best In Space?

Robonaut 2 Robert Markowitz/Bill Stafford/NASA/JSC

Robonaut, built by NASA and GM, is a head, torso and arms that will be anchored inside the International Space Station. After testing and upgrades, it will graduate to spending time attached to the station’s exterior, where it will be most useful. Astronauts’ bulky gloves make handling tools difficult; Robonaut could hang on to runaway tools and aid with more-complicated tasks. And whereas an astronaut takes at least six hours to prep for a spacewalk, Robonaut could boot up for emergency repairs in minutes.

Recognizing the need for more spacebots, the German Aerospace Center, DLR, has constructed Justin, a robotic torso with similar talents. “There is a friendly competition between us,” says Gerd Hirzinger, DLR’s head of robotics. Germany will probably need to work with other countries to put Justin on a Mars rover or the ISS, but one day the ’bot could rove on its own spacecraft, repairing satellites. Here’s how the two robots match up.

Round One: Strength
Justin: Even in microgravity, it takes force to move mass. Each of Justin's carbon-fiber arms can lift 31 pounds
Robonaut: Robonaut can lift just 20 pounds per arm, but that's enough to shift the ISS's giant solar batteries

Winner: Justin

Round Two: Vision
Justin: Stereo vision from two high-definition cameras and object-recognition software
Robonaut: Stereo vision plus an infrared camera for sonar-like depth perception to easily track moving objects

Winner: Robonaut

Round Three: Hands
Justin: Justin's four chunky fingers could have difficulty with normal tools, but its hands could swap out Mr. Potatohead-style for other gadgets
Robonaut: Robonaut's five human-size fingers let this robot use the same tools as astronauts. No special implements required

Winner: Robonaut

Round Four: Controls
Justin: From Earth, a person would control Justin by wearing an exoskeleton with force feedback
Robonaut: In the future, an astronaut will determine Robonaut's movements using a virtual reality helmet and a light-based motion-tracking system similar to an Xbox Kinect

Draw

Round Five: Power Supply
Justin: Mounted on its own spacecraft, Justin could get power from solar panels, with batteries for backup
Robonaut: Robonaut would wear exchageable battery backpacks for spacewalks, with conversion equipment to run off the ISS electrical system

Winner: Robonaut

Round Six: Programmed Dance Moves
Justin: John Travolta's twist from Pulp Fiction
Robonaut: Tai chi-like demonstrations of flowing grace and strength

Winner: Justin

And the winner is... Robonaut 2
Infrared vision, five-fingered hands and a tested power scheme make it the superior spacebot.