Prediction Method of Lunar Rover´s Tractive Performance Based on Similitude Methodology

In order to analyze low gravity influence to the tractive performance of lunar rover effectively, similitude methodology was introduced to investigate the lunar wheel-soil interaction. The key parameters of the system between lunar soil and rover wheel were selected at first, the terramechanical model of the system under lunar gravity was created according to similarity theorem, then the feasibility of model experiment approach was discussed. Since the cohesion of lunar soil is very low, a simple method was proposed to conduct the model experiment, with this method, both the wheel shape and wheel size are invariable, the rotation speed of model wheel is set as 2.45 times as the rotation speed of prototype wheel, the lunar soil simulant can be used as model experimental soil by remodeling the in-situ lunar soil state under ground gravity. In this case, both the drawbar pull and tractive torque obtained in model experiment are 6 times of their corresponding values under prototype condition, thus this method can be used to study a lunar rover´s tractive performance on moon surface. To test and verify this method in the next step, the related verification technique was also introduced.