Abstract: Taking the wheel-legged lunar rover with double-half-revolution mechanism as the research object, feet are added on both ends of the striking rod with the consideration of lunar rover’s sinkage problem when walking on the loose lunar surface. Two kinds of foot configuration schemes have been designed, in order to increase the effective contact area and their friction between the foot and lunar soil. According to the basic theory of terrain mechanics, the mechanical properties between the foot and lunar soil are analyzed. The mathematical models between the foot without wheel thorn and lunar soil are built up, and the influences of foot configuration parameters with wheel thorns are analyzed. Four driving performance evaluation indexes are proposed, including foot sinkage index, foot traction performance index, driving motor performance index and climbing performance index. Through the given characteristic parameters of the lunar soil, the lunar rover load and slip rate, the influences of foot radius/width and wheel thorn height/ number on hook traction and driving torque are simulated by Matlab software. The results show that the increase of the foot radius, height and width as well as the number of the wheel thorns can improve the driving performance of the lunar rover. Compared with the foot width, the increase of foot radius is better. The results provide a theoretical basis for the subsequent foot configuration design.

Key words: driving performance, evaluation index, foot configuration parameter, mechanical model, wheel-legged lunar rover