Discrete Element Modeling of Drilling Process into the Lunar Regolith Simulants of JSC-1A

Understanding the responses of lunar regolith during the drilling process in a low gravity environment is an important problem for geotechnical engineering in the realm of space exploration. Evaluation of the in situ physical and mechanical properties of lunar regolith will be essential for the development of in situ resource utilization (ISRU) capabilities as well as the construction of a permanent base on the Moon. However, due to limited access to the low gravity environment on the lunar surface, it is difficult to perform physical model tests to simulate the drilling process into the lunar regolith (or its simulants). The discrete element modeling (DEM) provides a useful numerical tool to investigate the behavior of the lunar regolith during the drilling process. This paper presents a discrete element modeling of drill-regolith interaction to evaluate the regolith behavior during the drill penetration process under the simulated lunar environment. The contact parameters for the discrete element modeling are calibrated using the triaxial testing results from lunar regolith simulants of JSC-1A. The responses during the drilling process such as tip and frictional resistance are monitored to evaluate the change of mechanical properties of the lunar regolith simulants with the depth.