Influence of lunar regolith compressibility on sampling performance of thick wall spiral drills  

作　　者：Yong PANG Tao ZHANG Hongyu WEI Ting ZENG Yinliang ZHANG Guidong MO Kun XU Shen YIN Guoxin WANG Xingwang ZHANG Xiaoming LAI Xilun DING 

机构地区：[1]Beijing Spacecrafts,China Academy of Space Technology,Beijing 100094,China [2]School of Mechanical Engineering and Automation,Beihang University,Beijing 100191,China [3]School of Electromechanical Engineering,Guangdong University of Technology,Guangzhou 510006,China

出　　处：《Chinese Journal of Aeronautics》2023年第2期350-362,共13页中国航空学报（英文版）

基　　金：financially supported in-part by the Pre-research project on Civil Aerospace Technologies by CNSA(No.D020201);the National Natural Science Foundation of China(No.51905105,51775011,11932001,51635002,and U2013603);the Natural Science Foundation of Guangdong Province(No.2020A1515011262);the State Key Laboratory of Robotics and Systems(HIT)(No.SKLRS-2020-KF12);the Technology Innovation Strategic Special Funds of Guangdong Province(No.2019A050503011)。

摘　　要：A 2 m class robotic drill was sent to the Moon and successfully collected and returned regolith samples in late 2020 by China.It was a typical thick wall spiral drill(TWSD)with a hollow auger containing a complex coring system to retain subsurface regolith samples.Before the robotic drill was launched,a series of laboratory tests were carried out to investigate and predict the possible drilling loads it may encounter in the lunar environment.This work presents how the sampling performance of the TWSD is affected by the regolith compressibility.Experiments and analysis during the drilling and sampling process in a simulated lunar regolith environment were conducted.The compressibility of a typical lunar regolith simulant(LRS)was measured through unidirectional compression tests to study the relationship between its inner regolith stress and bulk density.A theoretical model was established to elucidate the cutting discharge behavior by auger flights based on the aforementioned relationship.Experiments were conducted with the LRS,and the results show that the sampling performance is greatly affected by the flux of the drilled cuttings into the spiral flight channels.This work helped in scheduling reasonable drilling parameters to promote the sampling performance of the robotic drill in the Chinese Chang’E 5 mission.

关 键 词：Drilling mechanics Lunar drilling Lunar regolith compressibility Regolith sampling performance Thick wall spiral drill 

分 类 号：P18[天文地球—天文学]