Experimental Analysis on Multi-pass Effect of Small-lightweight Wheel on Loose Sand

Abstract

Mobile robots will play a key role in future extraterrestrial construction on the lunar surface. As the mobile robots traverse around the lunar regolith, their running gears, such as wheels, often generate ruts on the terrain. Those ruts after several wheel passes may significantly change the robotic mobility, which is called a multi-pass effect. While the multi-pass effect for heavy vehicles was addressed in the past, this paper aims to analyze the multi-pass effect for small-lightweight wheels experimentally. The experimental data obtained from our wheel test bench were qualitatively consistent with the past research on the multi-pass effect on large wheels. However, we found that the wheel slip ratio varied less than a few percent even though the number of runs increased. These results are then discussed based on the interaction mechanics of the wheel on loose sand.