Estimate of Impact Force at Landing on Lunar Surface by SPH Method

This paper describes how to predict the impact force and the penetration at landing on lunar sandy surface by SPH (Smoothed Particle Hydrodynamics) method. Before the calculations by SPH method, we conducted experiments about the landing on the lunar sandy surface. In experiment, 1/6 scale model of foot pad of landing gear, which was designed according to the 1/6 scaling laws, was dropped on the Regolith simulant foundation in vacuum chamber, and the impact acceleration and the penetration were measured. In calculations, the test bed of lunar simulant was modeled as Bingham fluid which had Mohr-Coulomb's failure criteria and the impact acceleration and the penetration of foot pad model was calculated. The results of computations by SPH method are in good agreement with the experimental results.