Design and manufacturing of rover wheels with knitted superelastic textiles.

Abstract

Recent interest in resuming manned space missions to the Moon, and eventually expanding to put humans on Mars, requires improving the vehicles previously used for driving on other planetary bodies. One such improvement is better rover wheel designs that enhance the ability of these wheels to survive driving across adverse terrain at higher speeds and loads without any permanent damage to the wheels, since some previous designs have sustained damage from prolonged driving. This research aimed to design a superelastic non-pneumatic wheel to enable large recoverable deformations and energy absorption while driving on other planetary surfaces. This goal was achieved by incorporating a superelastic knitted textile as the wheel's surface and a superelastic load-bearing radial structure. Novel manufacturing methods were established to create the superelastic knitted textile tread, allowing for customization of the properties of the textile, such as force response or Poisson’s ratio. A combination of theoretical and empirical modeling was used to design the superelastic radial structure of the wheel. A superelastic wheel prototype was created for laboratory benchtop testing and field testing, which successfully proved the validity of the theoretical modeling, demonstrated the qualitative performance of the wheel, and revealed improvements needed in future superelastic wheel designs. This research establishes a methodology to design future superelastic extraterrestrial and earth-bound off-road terrain wheels. Beyond wheels, the fundamental understanding of the impact of manufacturing and structural design parameters on the mechanical performance of superelastic knitted textiles will enable the design of textiles with large, fully recoverable deformations, large forces, and substantial energy absorptions for medical and wearable devices and consumer products.