Analysis on Depth Homing Characteristics of a Deep Fluted Auger for Lunar Soil Sampling

The sampling and in-situ analysis of water ice in the lunar polar regions is currently one of the major international research focuses in the field of deep-space exploration. The use of space robots equipped with deep fluted augers to drill into and sample water-ice-bearing lunar regolith permafrost is considered a sampling method with significant engineering feasibility. However， from a scientific perspective， the ability of this method to accurately determine the depth of origin of lunar regolith samples has not yet been verified. To address the scientific need for establishing a complete profile of lunar regolith through sample analysis， this study verifies the depth-resolution performance of deep fluted auger drilling. Based on a theoretical analysis of the flow characteristics of lunar regolith in deep fluted augers， permissible ranges for drilling procedures are established. Furthermore， the depth-resolution characteristics of the deep fluted auger are investigated through experimental testing. The experimental results show that more than 85% of the samples in the drill rod’s spiral flutes originate from the final 40 mm of drilling prior to rod retrieval， and this conclusion is largely unaffected by variations in drilling speed within the studied parameter range. Therefore， by employing step-by-step drilling and rod retrieval sampling within the same borehole， it is possible to establish a complete profile of the borehole.