An astronaut has successfully controlled a robot on Earth with micrometer precision, despite being 400km up and travelling at speeds of 28,800km/h.
Andreas Mogensen, the first Dane in space, used a feedback system to "feel" what he was doing 400km away. He commanded the Interact Centaur rover in real-time, using a joystick to drive it around before taking control of its robotic arm to place a peg into a hole on a circuit board.
The experiment was designed to replicate connecting a wire on another planet. With a tolerance of just 150 micrometers -- or less than one sixth of a millimetre -- it required precision and delicacy from both robot and human operator.
The first attempt at the experiment took 45 minutes, but a second run took only 10 minutes. During the second experiment Mogensen was able to "touch" the peg and sense how it felt using force-reflective technology in the joystick. Video streams captured by the robot gave him an overall view of his surroundings.
The main challenge of the experiment was the lag between a signal being sent and the robot acting on it. Signals sent by Mogensen travelled approximately 90,000km -- from the International Space Station, to Houston, Texas, on to the European Space Agency's research and technology centre centre in Noordwijk, the Netherlands and then back again. This results in a 850-millisecond delay.
Similar technology could one day be used by astronauts on Mars, allowing them to control robots from great distances with absolute precision.