Modeling of Autonomous Burrowing Mole-type Robot Drilling into Lunar Regolith

A reduced-order model is proposed to simulate the drilling and steering processing of an autonomous burrowing mole to access scientific samples from the deep subsurface of the Moon. The characteristic parameters of the locomotive module are considered including the length, cross-section diameter and centroid of a rigid rod. Based on the classical mechanics, a dynamic model for the locomotion of autonomous device underground is developed. By introducing the contact algorithm and resistive force theory, the interaction scheme between the locomotive body and regolith is described. The simulation results show that this method may model the directional drilling motions in the lunar subsurface environments. In addition, its full-3D behavior is also built by the coupled Eulerian and Lagrangian finite element method for the design purpose. Finally, the prototype of the steering mechanism is developed and validated. Overall, this robotic concept may provide intuitive inputs to enable the space missions of a drilling robot to obtain subsurface samples in an extraterrestrial planet, such as the Moon or Mars, etc.