Norcliffe, H. R.*; Watts, P.; Carrier, D. R.: Comparative Study of Human Locomotion in Microgravity

Because human locomotion evolved with the burden of gravity, locomotion is difficult in space. The absence of significant gravitational force could make human flight commonplace in a space station. To address this possibility, we analyzed mechanisms of animal locomotion applied to an astronaut in a space station. Our analyses indicate that humans could fly, but with relatively poor performance. Acceleration and turning agility would be much less than we are accustomed to on Earth, but limits on initial acceleration could be overcome, in most cases, by pushing-off from solid surfaces. With an initial take-off jump, relatively small wings mounted on the arms would give an astronaut a capacity to turn and change body orientation in a controlled manner. Because we are not structured to flap our arms as birds and bats do, we could produce greater accelerations using various methods of drag-based propulsion. Unfortunately, turning agility with drag-based propulsion would be limited by the intermittent generation of turning forces that is necessitated by the recovery stroke. The most versatile system of transport would likely be a space bike that would allow an astronaut to convert the muscular power of the human leg into a directed momentum flux of air, albeit with much less effort than needed on earth. Our results yield insight into the effect of gravity on the evolution of viable forms of animal locomotion. Our analyses also reinforce the efficient use of rotation by modern engineering.