3D DEM analysis on tractive trafficability of a lunar rover wheel with bionic wheel lugs

Abstract

African ostriches are good at running in the desert, and their toenails can effectively improve the tractivetraction performance in the running process. To improve the tractivetraction trafficability of wheels on the lunar surface loose soil, a wheel with bionic wheel lugs was designed based on the bionic prototype of ostrich toenail and bionic engineering technology. Then, the rolling of the bionic wheel was simulated by using the three-dimensional (3D) discrete element method (DEM) simulation system of the interaction between irregular structure wheel and lunar soil, and the result was compared with that of the wheel with rectangular wheel lugs. Under the same working condition, the drawbar pull, torque, and sinkage of two kinds of wheels at slip ratios of 0.25, 0.375, and 0.625 were analyzed. The simulation results showed that the average drawbar pull and average torque of the bionic wheel are greater than that of the wheel with rectangular wheel lugs at three kinds of slip ratios. When the slip ratios were 0.25 and 0.375, there was almost no difference in the average sinkage of the two kinds of wheels, but the average sinkage of the bionic wheel was significantly less than that of the wheel with rectangular wheel lugs when the slip ratio was 0.625. The results show that, compared with the wheel with rectangular wheel lugs, the bionic wheel has better tractivetraction and anti-subsidence performance. This study provides a new design and research method for improving the tractive trafficability of wheels in the lunar loose surface environment.