Measurement and modeling for two-dimensional normal stress distribution of wheel on loose soil. (December 2015)

• Record Type: Journal Article
• Authors: Higa, Shoya; Nagaoka, Kenji; Nagatani, Keiji; Yoshida, Kazuya
• Is Part Of: Journal of terramechanics. Volume 62(2015:Dec.)
• Page Start: 63
• Page End: 73
• Publication Date: 2015-12
• Subjects: Planetary rover -- Rigid wheel -- Stress distribution -- Modeling; Trafficability -- Periodicals; Praticabilité (Routes) -- Périodiques; Trafficability; Periodicals; 629.222
• DOI: 10.1016/j.jterra.2015.04.001
• Languages: English
• ISSNs: 0022-4898

Abstract

Highlights: We developed a method to measure two-dimensional stress distribution beneath a wheel. The stress distribution shows a mountain-shape in the wheel's width direction. The distribution area moves to a forward part along with the increase of slip ratio. We constructed a model of the stress distribution based on the experimental data. We reconstructed entire normal stress distribution from two points' data. Abstract: On the Moon or Mars, typical target environments for exploration rovers are covered with fine sand, so their wheels easily slip on such weak ground. When wheel slippage occurs, it is hard for the rover to follow its desired route. In the worst case, the rover gets stuck in loose soil and cannot move anymore. To reduce the risk of the rover getting stuck, analysis of the contact mechanics between the soil and wheel is important. Various normal stress distribution models for under the wheel surface have been proposed so far. However, classical models assume a uniform stress distribution in the wheel's width direction. In this study, we measured the two-dimensional normal stress distribution of a wheel in experiments. The results clarified that the stress distribution in the wheel's width direction is a mountain-shape curve with a peak located at the center of the wheel. Based on the results, we constructed a stress distribution model for the wheel's width direction. In this paper, we report our measurements for the two-dimensional stress distribution of a wheel on loose soil and introduce our stress distribution model for the wheel's width direction based on our experimental results.