Dynamic-compacting based lunar soil simulant preparation for subsurface exploration

Abstract

Compared to other technical methods, drilling and coring by only using the compound motions of rotation and penetration can sample subsurface lunar soils relatively efficiently. Considering that drill tool's power consumption and soils' coring morphology are both determined by external operating parameters and physical properties of in-situ soils, the influence by drilling parameters on a certain formation should be investigated firstly. To remove the coupling effect by lunar soils' physical properties, one type of homogeneous lunar soil simulant along the longitudinal direction is urgently necessary for verification experiments. Herein, a dynamic-compacting based lunar soil simulant preparation method is proposed to tamp the raw soil material into a relatively dense and uniform state. A group of optimized lunar soil preparation parameters has been acquired by analyzing the dynamic interaction process. Experiments under a high speed camera's online monitoring indicated that under over 12 cycles of tamping the raw soil can be compacted into a homogeneous state along about 200 mm depth, which is consistent with the analytical results. The longitudinal density of the compacted soil simulant is also close to the value of lunar soil. Therefore, further orthogonal sampling experiments will be conducted in this lunar regolith simulant.