Stabilizing the Lunar Flagpole by Optimizing the Structure and Insertion Method

The act of planting a flag on the moon carries immense significance in the realm of human space exploration. Therefore, this paper develops a discrete-element method–finite-element method (DEM–FEM) coupling algorithm to simulate the flag planting process. To enhance the stability of a flagpole installed on the lunar surface, the structure of the flagpole is optimized, with the bottom end designed as a cone and a stabilizer bracket added. Three flag insertion methods are proposed: direct insertion, percussion insertion, and rotation insertion. The stability of the flagpole given external disturbances is thoroughly discussed. The results demonstrate that the cone design at the bottom of the flagpole effectively enhances its depth in the soil. Although the addition of a stabilizer bracket does not facilitate the flagpole’s penetration into the lunar surface, it increases its resistance to external interference. Given appropriate conditions, the three insertion methods can significantly increase the depth of the flagpole into the soil. The stability analysis reveals that, in the face of constant external interference, flagpoles with greater depth experience less horizontal displacement and require a larger external load to collapse, indicating enhanced stability. Overall, this research provides practical solutions and theoretical references for the manual placement of flags on the lunar surface.