In lunar soil drilling, stones have significant influences on sampling. Herein, stones are classified into greater stones and supramaximal stones based on their sizes. Five simulation conditions with different sizes and positions of the stone were designed. The stone trajectories, sampling efficiencies, velocity field, stress field and load curves were compared and analyzed. The results indicated that the resultant axial force and torque were mainly decided by the load of the bit. The stone affected the stress of the particles around it obviously, but had little effect on the velocity field. A greater stone, having diameter smaller than that of the virtual cutting circle of the drill bit, has little influence on the lunar soil drilling process. However, a supramaximal stone, with diameter larger than that of the virtual cutting circle, significantly affects the lunar soil drilling process. If supramaximal stones are near the edge of the virtual cutting circle, they are easily spun out and can cause obvious discrete pulse peaks of axial force. If the supramaximal stones are screwed inward, they can easily cause a jam in front of the drill bit, making the soil injection difficult. An experiment result verified the effect of the supramaximal stone.

在月球土壤钻探中，石头对采样有重要影响。在此，根据大小将结石分为大结石和超最大结石。设计了五种不同大小和位置的模拟条件。比较并分析了石材的轨迹，采样效率，速度场，应力场和载荷曲线。结果表明，合成轴向力和扭矩主要取决于钻头的负荷。石头明显影响了其周围颗粒的应力，但对速度场的影响很小。直径小于钻头虚拟切割圆直径的更大的石头对月球土壤钻探过程的影响很小。但是，直径大于虚拟切割圆直径的超最大石材，严重影响月球土壤钻探过程。如果超大结石靠近虚拟切割圆的边缘，则它们很容易旋转，并可能导致明显的轴向力离散脉冲峰值。如果将最大的石头向内拧紧，它们很容易在钻头前面造成堵塞，从而使注土变得困难。实验结果证实了超最大结石的效果。