Abstract

Sampling extraterrestrial soil, which reveals the composition and origination of celestial bodies, is one of the key technique in planet detecting. Penetrating soil with hollow cylinder is one simple, highly reliable and environmentally adaptable way to sample soil, but the sampling depth is limited by the penetration force of the sampling system. The penetration characteristics of the sampler are determined by the structural parameters and soil parameters. The study first presents a model to predict the inner wall friction in the frame of Janssen theory and continuum model hypothesis for future food production projects. The outer wall friction is then modeled according to the hypothesis that the soil outside the sampler is a semi-infinite body. The bearing force of the soil underneath the bottom of the sampler is calculated via the ground ultimate bearing capacity theory. The overall penetration force is the sum of the inner wall friction, outer wall friction and the bearing force. The consistency of the model predictions and experimental data is verified. The research in this study provides a theoretical basis for lunar surface sampling.

Keywords:

Food production projects, Janssen theory, lunar surface sampler, penetration,

References

1. Houston, W.N., H.J. Hovland, J.K. Mitchell and L.I. Namiq, 1972. Systems for extraterrestrial subsurface exploration. Proceeding of the Lunar Science Conference, 3: 3255.
   
2. Houston, W.N., J.K. Mitchell and W.D. Carrier, 1974. Technologies for exploring the Martian subsurface. Proceeding of the Lunar Science Conference, 5: 2361.
   
3. Jing, Y.M. and H.P. Zheng, 2008. Some surface area and porosity characterizations of lunar soils. Acda. Phys. Sin., 57: 7360.
   
4. Roberts, I., 1984. Particle size and shape distribution for lunar fines sample. Proc. Roy. Soc., 36: 226.
   
5. Vanel, L., P. Claudin, J.P. Bouchaud, M.E. Cates and J.P. Wittmer, 2000. Effects of granular size on stress transmission in a granular column. Phys. Rev. Lett., 84: 1439.
   CrossRef    PMid:11017537    

Competing interests

The authors have no competing interests.

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Copyright

The authors have no competing interests.