Analysis of Elastic Wheel Performance for Off-road Mobile Robots using FE—DEM

For this study, we applied a finite element-discrete element method (FE-DEM) to predict the tractive performance of an elastic iron wheel for mobile robots running on sand. We developed our program, where FEM is applied to a wheel and a subsurface soil layer, and where DEM is applied to the surface soil layer where the contact interaction between the tire and soil is greatest. The developed FE-DEM tool was found to have sufficient accuracy to predict the performance of an elastic wheel running on deformable soil. Moreover, parametric analysis was applied for those parameters of the rigidity of the tread part of the wheel, the surface soil layer thickness, and the lug height. The effect of rigidity of the tread part was negligible for 1-5 MPa. The surface soil layer thickness was found to have no significant effect on tractive performance. The lug height showed a strong effect on the tractive performance of the wheel, but the effect on net traction seemed to be degraded concomitantly with the increase in lug height.