# Numerical Simulations of Regolith Sampling Processes

## TL;DR

This paper improves numerical simulations of regolith sampling in microgravity using SPH, analyzing how material properties and environmental factors affect sampling efficiency for asteroid missions.

## Contribution

It introduces enhanced SPH-based modeling of regolith sampling, incorporating elastic-plastic soil behavior and varying environmental conditions.

## Key findings

- Simulation results align well with Earth experiments.
- Material cohesion and friction influence sampling rates.
- Surface gravity and brush rotation affect collection efficiency.

## Abstract

We present recent improvements in the simulation of regolith sampling processes in microgravity using the numerical particle method smooth particle hydrodynamics (SPH). We use an elastic-plastic soil constitutive model for large deformation and failure flows for dynamical behaviour of regolith. In the context of projected small body (asteroid or small moons) sample return missions, we investigate the efficiency and feasibility of a particular material sampling method: Brushes sweep material from the asteroid's surface into a collecting tray. We analyze the influence of different material parameters of regolith such as cohesion and angle of internal friction on the sampling rate. Furthermore, we study the sampling process in two environments by varying the surface gravity (Earth's and Phobos') and we apply different rotation rates for the brushes. We find good agreement of our sampling simulations on Earth with experiments and provide estimations for the influence of the material properties on the collecting rate.