Effect Analysis of Particle Shape in Lunar Soil Drilling Process

To find out the influence of particle shape on the force situation and sampling efficiency of the drilling tool, the discrete element method is employed to build the lunar regolith model and simulate the interaction between soil and drilling tool. A three-dimensional contact model is introduced to represent the impact between particles. To make sure the validity of the model, a triaxial-test is conducted to optimize the micro-parameters of the model. Then, the model is employed to the simulation of drilling process. From the computational simulation results, conclusions can be made: the particle shape will change the interlocking between particles, and the strip particles have the largest interlocking which makes the force situation largest and the sampling efficiency smallest.