| The structure of a wheel intended for lunar applications requires an innovative design because of the Moon's specific environment. As in-situ prototype testing is obviously unfeasible, testing can only be conducted on lunar simulant soils, or through simulations. This study presents wheel-soil interaction simulations using the discrete element method (DEM) software EDEM and their use for tread shape optimization.;Then, two different approaches of three-dimensional wheel-soil simulations are described. The first approach involves a displacement-controlled wheel, its tractive performance being measured for various grouser configurations. In the second approach, the wheel is torque-controlled and performances, such as power consumption or speed, are investigated and validated experimentally.;This work proposes a soil simulation and shape optimization tool for the design of a rigid wheel tread that targets a need of the Canadian aerospace industry.;The DEM parameters of EDEM's contact-model are first reviewed before presenting a systematic methodology of their calibration. The first step consists in measuring key properties of the real soil with basic experiments and simulating these experiments for different values of the virtual soil's design variables. The soil's response surfaces of the targeted properties are then computed, and an optimization algorithm is developed to determine the optimum sets of design variables that minimize the discrepancy of the properties between the real soil and the virtual one. |
