AGBRESA – "In 'space', you have plenty of time, but no fuel station nearby" – docking training
Navigating a spacecraft through the endless expanse of the cosmos and performing difficult manoeuvres under adverse conditions to dock safely with the Space Station – what sounds like the childhood dream of any hobby astronaut is in fact a routine task for participants in the AGBRESA bed-rest study. Learning how to control a spacecraft with six degrees of freedom or 6df, to use the more usual term, is one of the numerous experiments that study participants are required to complete. The spaceflight, however, is carried out in a lying-down position in Cologne to be compatible with the requirements of the bed-rest study. By the time the study is over, the participants will each have completed 20 docking 'sessions' in total, acquiring the necessary skills to control a spacecraft and – if everything goes according to plan – dock it safely with the Space Station.##markend##
Some participants are quick learners, while others need a little more time. But Bernd Johannes, a space psychologist at the DLR Institute of Aerospace Medicine who developed the program, is well aware that speed tends to be counterproductive:
"Daredevils who are experienced gamers and quickly learn to control our system of movement using the joystick run into difficulties when they fly too fast and forget that there is no resistance to movement in space. Quite often they will crash or drift off and are then surprised when the program doesn't compensate in any way. That's why I always tell them that there's one thing that is not in short supply in space – time. In contrast, only limited quantities of fuel and oxygen are available."
Slow and steady wins the race
The computer enthusiasts among the bed-rest participants find it easier to develop their flying skills but tend to travel too fast. Others with no gaming experience generally take longer. But Bernd Johannes has not identified any differences between men and women in the preliminary studies; while the learning curve might take a little longer among the women, the end performance is the same for both genders.
A new aspect of the AGBRESA study docking experiment is that there is now a 3D version of the training program. In order to determine whether this option facilitates intuitive learning of the difficult flight manoeuvre, half of the bed-rest participants wear virtual reality googles to test the new 3D version, while the others complete the experiment using the standard 2D version. Bernd Johannes predicts that stereoscopic vision with a VR headset will enable greater spatial awareness and will therefore improve the learning process. An eye-tracking feature was also incorporated to record eye movements during the training as a means of determining a possible correlation with performance. This is because the test subjects are required to gauge speed depending on the distance to the destination, namely the Space Station.
The system underlying the 6df program was designed and implemented by Bernd Johannes himself at the Institute of Aerospace Medicine. Its modification for the bed-rest study was also done there; the institute's own workshop built the assembly in which the participants complete the experiment lying down while operating the joystick and looking at the monitor above their heads: "You can't get equipment like this off-the-shelf," Johannes proudly declares. The program he has worked on for 14 years already is also self-made; he developed it himself and has tested it with 22 participants at DLR, 30 in Philadelphia, USA and 17 in Moscow, Russia, before creating an adapted version to test the skills of the AGBRESA participants. The ability to manually dock a spacecraft with a space station has become an important aspect of crewed spaceflight. The application was developed to investigate and support the acquisition and maintenance of these docking skills during long-term missions. Not only motor skills but also psychological skills play a role in the training. Understanding the complex spatial situation and the simultaneous, synchronous control of six degrees of freedom using two different joysticks are among the key skills that are acquired during the training.
Like the Russian original
Each training session lasts 45 minutes. The docking experiment only takes place during the bed-rest phase of the study. The participants are taken to one of the two docking rooms in Module 5 adjacent to the participant's quarters, where they complete the flight test. The space vehicle is controlled using two joysticks which function in exactly the same way as their original Russian counterparts. "For many of our test participants, the training is the highlight of the week!," say Bernd Johannes and his doctoral candidate Sarah Piechowski with visible delight. Now that half of the training programme has been completed, they are starting to notice that the participants are becoming more adept at flying and are pleased with the large amounts of data that they have already started to analyse. This is a reward for the immense dedication of the test participants and the investigators, who are on site almost every day.