Numerical analysis on traction performance of trapezia lugged wheel by distinct element method

The soft-terrain trafficability of trapezia-lugged wheel on lunar surface was analyzed by distinct element method (DEM). The modeling technology of DEM was presented to produce irregular-shaped particulate system. The mesoscopic formula of traction performance for wheel was built. Based on simple shear test data, the optimal parameters of lunar simulant particles were obtained by repeated debugging. It is shown from analyzing wheel-soil interaction that there is relationship between traction performance and slip ratio as well as lug configuration. The higher drawbar pull can be obtained as increasing slip ratio, however the driven torque will be enhanced simutanously. Furthermore, bigger lug height produces higher soil thrust, but the motion resistance increases together. The influence of lug's number on wheel's traction performance is negligible, whereas it influences on smooth-running of wheel.