The two-way communication system incorporating force feedback that astronaut Andreas Mogensen will be using to operate the Interact Centaur rover down on Earth and perform sub-millimetre precision ‘pin-in-hole’ experiment. As the astronaut moves his haptic joystick and support arm, the resulting signals travel from the ISS in 400 km altitude Earth orbit up to a constellation of
TDRSS satellites in geosynchronous orbit 36 000 km up, then down to a ground station in New Mexico, relayed in turn to NASA Houston and then via a trans-Atlantic fibre-optic cable to ESTEC in Noordwijk, the Netherlands, ending up received by the rover. He then receives video and force feedback data in return. The signal must cover a long distance of nearly 90 000 km.The resulting two-way time delay approaches one second in length.