针对深层月壤采样过程钻具参数对钻具受力及月壤采样量的影响问题，开展了离散元仿真分析。建立考虑扭转、弯曲力矩及等效引力作用的新型三维离散元月壤模型，通过三轴仿真试验进行细观参数标定，得到内聚力0.90 kPa、内摩擦角42.25°的满足真实月壤宏观力学指标的仿真模型。选取钻头立齿形状、头体形状，钻杆导程、牙宽，回转转速等重点钻具参数进行对比分析，仿真结果表明：圆柱立齿有利于月壤采样，而八角立齿有利于钻具受力，"漏斗"形头体相比于"圆锥"形头体受力较小；钻杆导程的增加会使得月壤采样量增大，但同时也会使得钻具受力增大，钻杆牙宽取3 mm时月壤采样量最大、钻具受力最小；回转转速过大，月壤采样量会急剧减小，回转转速过小，钻具受力会急剧增大。
A discrete element simulation analysis is carried out to analyze the influence of drilling tool parameters on the force of drilling tools and soil sampling in the deep lunar soil. A novel 3D discrete element model considering the bending and twist moment and equivalent attractive force is built firstly, and then, a triaxial simulation test is conducted to calibrate the micro-parameters. The mechanical macro-parameters of the model are calculated:the cohesion is 0.90 kPa and the internal friction angle is 42.25°, meeting with that of the real lunar soil. Key parameters of drill tool such as drill bit tooth shape, body shape, drill stem lead, tooth width, rotary speed are compared and analyzed. The simulation results show that the cylindrical vertical teeth are beneficial to soil sampling, and octagon vertical teeth are beneficial to drill force; drill force of the funnel shaped head is less than that of the cone shaped head; the increase of drill pipe lead will increase the soil sampling, but it will also increase the load; the width of drill pipe thread of 3mm is suitable for more soil sample and less load; with the rotating speed increasing rapidly, the lunar soil sample decreases seriously; with the rotating speed decreasing rapidly, the drill load increases obviously.
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