Researchers simulate hand movements in zero gravity with exoskeleton
An exoskeleton is intended to prepare astronauts on Earth to perform complex hand movements in zero gravity. Tests are still needed.
During a parabolic flight under microgravity, a test subject performs a hand movement previously learned with an exoskeleton under gravity.
(Image: DFKI)
Scientists from the German Research Center for Artificial Intelligence (DFKI) and the University of Duisburg-Essen (UDE) have developed an exoskeleton that can simulate hand movements in zero gravity. This allows training conditions similar to microgravity to be replicated on Earth. Hand movements, for example, for repairs and scientific experiments in zero gravity, could thus be practiced in advance.
A person's fine motor skills can be measurably impaired by microgravity; write DFKI and UDE in a press release. However, for difficult tasks in zero gravity, such as repairs on board a space station and conducting experiments there, every hand movement must be precise. In addition, the cognitive and physical load increases when faulty hand movements have to be repeated.
The exoskeleton developed in the MIkroBEM project by the Robotics and Innovation Center of DFKI and UDE is intended to help simulate fine motor movement sequences under gravity on Earth, similar to space conditions. It compensates for the weight of the human arm through targeted force support, thereby reducing the load. The simulation of zero gravity is achieved using artificial intelligence (AI). This allows the supporting force to be individually controlled depending on the user of the exoskeleton to simulate conditions as realistically as possible.
Testing
To determine whether a training effect can be achieved using the exoskeleton, the researchers used two groups of test subjects. The first group practiced the task of touching the center of a screen with the index finger of their right hand using the exoskeleton over a period of several weeks. The arm was covered to avoid movement-correcting interventions through visual feedback. During the experiment, the researchers recorded the muscle and brain activity, heart rate variability, and movement trajectories of the test subjects. The second group did not practice the task. They were merely instructed about the experiment and its setup.
The two groups of test subjects then had to perform the task under zero gravity. For this purpose, they participated in the 46th parabolic flight campaign of the German Aerospace Center (DLR) in Bordeaux in May. Parabolic flights with the specially equipped Airbus A310 “Zero G” generated periods of weightlessness lasting 22 seconds each. A total of eleven minutes of microgravity was achieved per flight.
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The scientists recorded data from a total of 180 parabolic flights. There were no measurement failures. The data will now be evaluated to determine whether there is a training effect from the pre-training with the exoskeleton. Data already collected suggests that this is the case. The newly collected data is intended to validate these results as much as possible after evaluation.
If the training effect is confirmed, astronauts could potentially be better prepared for their tasks in space before their space missions with such a robotic exoskeleton.
(olb)
