This paper discusses the safe landing process of a reentry capsule in detail with respect to landing attitude and rebound response. First, the discrete-element method (DEM) of the land soil and the finite-element method (FEM) of the reentry capsule structure are established. The dynamic response of the reentry capsule landing are analyzed using the DEM-FEM coupling algorithm and then compared with the results obtained from experiment and LS-DYNA. Second, the effects of the landing velocity and attitude on the landing process are discussed. Finally, the effects of mass and friction coefficient between particles on the rebound response of the reentry capsule are analyzed. The study shows that soil particles contribute to the absorption of the impact energy of the reentry capsule. The inclined landing is more conducive to the safe landing of the reentry capsule. The rebound velocity of the reentry capsule is relatively smaller when the friction coefficient between the particles is smaller and the mass of the reentry capsule is larger.

Airborne electromagnetic (AEM) surveys map subsurface electrical structures by deploying transmitter and receiver coils on an airborne platform. However, platform-induced vibrations are transmitted to the sensors, generating strong motion-induced noise that severely degrades signal quality. To mitigate such noise, this study proposed the use of granular materials as a cushioning medium. An impact model based on the Discrete Element Method (DEM) was developed and validated against drop-weight experiments. Both granular material properties and impactor characteristics were investigated. The study examined the cushioning effects on both the base plate and the impactor under impact loading, and the sensitivity of key parameters was evaluated. The results showed that granular properties had minimal influence on the impactor peak force. Increasing particle Young’s modulus, density, or friction coefficient led to higher peak forces on the base plate, with Young’s modulus and density having significantly stronger effects than friction coefficient. Additionally, both the impactor size and velocity correlate positively with the peak forces transmitted to the base plate and experienced by the impactor. Under thin layer conditions, the impactor force was more sensitive to impact parameters, while in thick layers it was mainly determined by particle rearrangement and energy dissipation mechanisms. These findings reveal the mechanisms governing granular cushioning and provide a theoretical basis for vibration isolation design in AEM systems to preserve high-fidelity signals.