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Perception of body angular displacement while free-floating in microgravity during parabolic flight.
Gilles Clément1,2, Olga Kuldavletova3, Gaëlle Quarck3
1KBR, Houston, TX, United States. gilles.r.clement@nasa.gov.
Summary
Human motion perception differs across rotation axes in microgravity. Astronauts may face challenges with orientation-dependent tasks due to inaccurate self-motion estimation without gravity cues.
Area of Science:
- Human physiology
- Neuroscience
- Space biology
Background:
- Accurate self-motion perception is vital for spatial orientation.
- Environments like spaceflight lack typical visual and gravitational cues.
- Understanding motion perception in microgravity is crucial for astronaut safety and performance.
Purpose of the Study:
- Investigate human perception of passive whole-body rotation in microgravity.
- Analyze self-motion perception during yaw, pitch, and roll rotations.
- Determine axis-dependent differences in motion perception without gravity.
Main Methods:
- Six participants underwent passive whole-body rotations (30-420 degrees) in microgravity during parabolic flight.
- Rotations were performed about yaw, pitch, and roll axes.
- Perceived angular displacement was reported, with visual/auditory cues eliminated and motion tracked by inertial sensors.
Main Results:
- Perception errors were larger for pitch and roll rotations compared to yaw.
- Inaccurate estimation of rotation amplitude increased with larger angular displacements.
- Perception gain showed greater variability for pitch and roll, and was higher for roll, potentially influenced by velocity.
Conclusions:
- Axis-dependent differences in microgravity motion perception exist, likely due to absent otolith input and altered tactile feedback.
- Gravity's role in perceiving pitch and roll motion is significant.
- Inaccurate rotation estimation poses operational challenges for astronauts and informs vestibular rehabilitation.
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