Yes Runs Doom Satellite: ESA Cubesat Obeys Voice Command
Norwegian radio amateurs spoke a command from an Oslo rooftop on July 27 and an ESA-linked satellite, PRETTY, launched the 1993 shooter Doom. Tanagra Space supplied the software. The team says the first orbital voice control could help rescue services hear distress calls.
A European Space Agency-linked cubesat called PRETTY launched the 1993 shooter Doom after Norwegian radio amateurs spoke a command to it from a rooftop in Oslo on July 27, in what its team describes as the first demonstration of orbital voice control. Yes, it runs Doom: the satellite transcribed the spoken words on board and opened the game.
Playing a video game was never in the design plan for PRETTY. The cubesat is run by a consortium that includes ESA.
How the command worked
Jon Bergli Heier, call sign LB9BJ, spoke the command at night. In part it was "PRETTY play Doom Doom Doom." The satellite picked up the transmission, transcribed it with on-board voice recognition and started a play session.
It was a one-player affair. PRETTY then produced a "postcard" containing a frame of the gameplay, a transcription and signal diagnostics. It also sent back its recording of the spoken command.
The software came from Estonia's Tanagra Space. OPS-SAT Space Lab managed the experiment on behalf of ESA.
Seven attempts, 59 days
Success did not come quickly. Radio amateurs made six unsuccessful attempts during passes over Poland and Norway between April and July. The seventh, by the Oslo Group of the Norwegian Radio Relay League, worked.
The Norwegians spent 59 days and about 7200 NOK, or $775, pizza included. A raw recording of a July 3 attempt, retransmitted to Earth, showed the words were unrecognizable. Further work found the satellite's receiver channel was too wide to pick up the voice signal, so the team narrowed it.
Doppler shift and an antenna not built to relay voices added to the difficulty. The system ran on open-source tools: GNU Radio handled signal processing and Sherpa-ONNX handled speech recognition.
Why the team cares
Tanagra Space says the technique could one day help people in trouble. "Someone in distress at sea or in a remote area could transmit 'mayday' or "help" on a radio," the company stated. The hope is that a satellite could use transcription and AI to alert rescue services.
Future spacecraft might also apply the approach to non-voice radio signals. One idea is a satellite that detects deep-space radio signals and sends operators the most relevant data after analyzing them with on-board AI.
PRETTY is not the first satellite to play Doom, but receiving voice commands was the achievement here.
"We are radio amateurs, with the emphasis on amateurs," said Eskil Hadland, call sign LB6AJ, in Tanagra's statement. "Our tiny ground station shouted at an ESA spacecraft, and was heard."
