Rendezvous and docking
The second set of ATV lessons focus on the 'ATV Rendezvous and Docking' manoeuvres. The trainees learn to perform the operations needed when the ATV arrives at the Station - a process called 'rendezvous' since the ATV is 'meeting the Station'.
After launch, ATV may orbit the Earth for a number of days prior to starting rendezvous with the ISS. Since the first ATV flight is considered a test flight, there are two demonstration days prior to the docking day.
During these demonstration days, the ATV Control Centre (ATV-CC), in Toulouse, France, and the crew on board ISS send various commands to the spacecraft and check that the ATV responds correctly to each command.
The demonstration of these manoeuvres ensures that the sensors and the guidance, navigation and control system onboard ATV can safely approach and dock with the ISS. ATV docking is lead by sensors that recognise the correct docking area and initiate the process in a very precise manner.
So why do the astronauts have to train for ATV docking if it is automated?
To begin with, the ATV is a new vehicle that has never flown in space before. In addition, its primary sensor for close range navigation has never been used before on another spacecraft. Therefore, the first ATV flight is considered a test flight.
The crew can see the ATV using a video camera mounted on the Station and a specially designed target on the ATV. With this video image, the crew can judge whether the ATV is flying within a corridor aligned with the docking port on the Station. This ability allows the crew to monitor ATV and provides an additional level of safety to what is already implemented onboard the spacecraft.
Finally, given that the ATV is the size of a double-decker London bus and it docks with the ISS, which is a manned space station, every possible precaution is used. For these reasons, the astronauts are trained to monitor the rendezvous and docking of the ATV.
The docking and undocking manoeuvres are trained both in a simulator and in the high fidelity ATV mock-up.
In the simulator, the crew learns how to handle the control workstation called TORU. The workstation includes the 'Simvol' screen – with which the astronauts monitor the ATV's approach to the Station – and a Russian laptop which is the same as one used on the Station.
Step two of the docking and departure training sees the trainees move inside the mock-up, where they operate in situ. There, an instructor guides the trainees and at the same time acts as the ground voice communication.
