Dynamics of Extra-Vehicular Activities in Low-Gravity Surface Environments

  • Spencer, David A. (Georgia Institute of Technology, School of Aerospace Engineering) ;
  • Gast, Matthew A. (Georgia Institute of Technology, School of Aerospace Engineering)
  • Received : 2013.02.04
  • Accepted : 2013.02.18
  • Published : 2013.03.30


Human spaceflight experience in extra-vehicular activity (EVA) is limited to two regimes: the micro-gravity environment of Earth orbit, and the lunar surface environment at one-sixth of Earth's gravity. Future human missions to low-gravity bodies, including asteroids, comets, and the moons of Mars, will require EVA techniques that are beyond the current experience base. In order to develop robust approaches for exploring these small bodies, the dynamics associated with human exploration on low-gravity surface must be characterized. This paper examines the translational and rotational motion of an astronaut on the surface of a small body, and it is shown that the low-gravity environment will pose challenges to the surface mobility of an astronaut, unless new tools and EVA techniques are developed. Possibilities for addressing these challenges are explored, and utilization of the International Space Station to test operational concepts and hardware in preparation for a low-gravity surface EVA is discussed.


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