Stick-slip Dynamics in Penetration Experiments on Simulated Regolith

Abstract The surfaces of many planetary bodies, including asteroids and small moons, are covered with dust to pebble-sized regolith held weakly the surface by gravity contact forces. Understanding reaction an external perturbation will allow for instruments, sensors anchoring mechanisms use on such surfaces, implement optimized design principles. We analyze behavior a flexible probe inserted into loose simulant as function speed ambient gravitational acceleration explore relevant dynamics. EMPANADA experiment (Ejecta-Minimizing Protocols Applications Needing Anchoring or Digging Asteroids) flew several parabolic flights. It employs classic granular physics technique, photoelasticity, quantify dynamics during its insertion system bi-disperse, centimeter-sized model grains. identify force chain structure throughout at variety speeds four different levels gravity: terrestrial, Martian, lunar, microgravity. discrete, stick-slip failure events that increase in frequency acceleration. In microgravity environments, behaviors negligible, we find faster can suppress where they present. conclude mechanical response rubble-pile is likely quite distinct from found larger objects, scaling terrestrial experiments conditions may not capture full physical