DEM simulation of footpads quasi-statically penetrating into granular ground

Abstract

The bearing capacity of a footpad used in a typical lunar detector is investigated using distinct element method (DEM) with a focus on the effect due to the wing plate of the footpad. In DEM simulation, a series of footpads with varying curvatures of wing plates were configured to penetrate quasi-statically into a granular ground. The ultimate capacity of the footpad is obtained from the relationship between the penetration resistance and the penetration displacement. The results indicate that the ultimate bearing capacity of the footpad is largely affected by the curvature radius of the wing plate. A smaller radius, i.e., smooth transition between the base and wing plates, is beneficial for a larger bearing capacity due to increasing contribution of the wing plate. The failure wedge of soils underneath the footpad is also affected by the wing plate. The wedge becomes shorter due to the presence of the wing plate.