The after the Italian physicist Edoardo Amaldi (1908-1989) named third ATV (Automated Transfer Vehicle) of the European Space Agency ESA has docked fully automatic and absolutely accurate to the International Space Station in the night from Wednesday to Thursday.
In this manoeuvre the rendezvous and docking sensors RVS TGM (Telegoniometer) and RVS VDM (Videometer) of Jena-Optronik GmbH have been used. This was the seventh docking monoeuvre within a total of 15 successful years where the sensors proved their performance capabilities. On two shuttle missions to the MIR space station in 1997 the prototype of the sensor showed its performance.
Today, in addition to the ESA, the Japanese space agency JAXA as well as the American Cygnus are using the highly precise opto-electronic sensors on board of their HTV-transport vehicles.
After the launch of the ATV-3 from Guayana Space Center aboard the launch vehicle Ariane 5 ES the RVS starting its work from a distance of 1500 meters to the ISS.
To determine the distance and position of the ISS during the approach, short laser flashes are emitted, which are reflected from reflector mirrors on the ISS. The sensor calculates from the propagation of the laser light the distance to the space station. Using the precision scanning mirror sensor, the ISS is sampled and its location determined. The ATV onboard computer uses this information to control the automatic rendezvous with the ISS. The ATV-3, which has a weight of 20 tons and a span width of 22 meters, is currently the largest transport vehicle to the ISS that supplies the astronauts with food and water and provides important tools for scientific experiments to the space station. After a controlled undocking the ATV will burn up in Earth's atmosphere.