Design and Mobility Evaluation of a Crawler-Type Lunar Vehicle

This paper describes a newly designed crawler-type vehicle for the Moon exploration. It aims at achieving higher mobility for bigger and heavier transportations in the future as well as enhancing the mobility of current small or medium sized robotic vehicles, focusing on the slope-climbing capability on pure sand slopes. The designed vehicle has four mesh crawlers to reduce weight and the number of parts. A single crawler test was conducted using a slope traveling test apparatus to obtain the effects of slope inclination on the relationships between slip ratio and vertical load, or between ultimate current and vertical load. The results show that there is an optimal design point for the contact area and that the design point is fairly robust for the weight increase. The power consumption of the single crawler increased linearly along the traveling distance for all the test cases, which means that the slip ratio and current were stable during the test traveling. A single wheel test was conducted for comparison. The wheel's slip ratio and power consumption were bigger than that of the crawler at a slope of 20 degree and its power consumption increased non-linearly along the traveling distance. The test results obtained so far indicate that a crawler-type vehicle shows higher performance and lower power consumption than a wheel on steep slopes under the experimental condition.