Stress distributions of a grouser wheel on loose soil

Measurement of stress distribution at the contact patch is the best way to understand the wheel–soil interaction on loose soil because the wheel only interacts with the terrain at the contact patch. Grousers attached to the wheel rim upgrade the mobility performance of the wheel on loose soil; however, the stress distribution of the grouser wheel has not yet been elucidated. Understanding of the interaction between the grouser wheel and the soil contributes to the improvement in the mechanical model of the grouser wheel, and will be helpful to estimate the terrain parameters beneath the wheel. In conventional approaches, it is assumed that the traction of the grouser wheel can be expressed by merely adding bulldozing effects of the grousers into the rigid wheel model, or can be addressed as the enlargement of the wheel diameter; however, the experimental investigations are not enough. For more appropriate modeling and design of a grouser wheel, the stress distribution of a grouser wheel should be revealed. Therefore, this article addresses the experimental investigation of the stress distribution on a grouser wheel. Experimental results reveal that almost all tractive components of the grouser wheel are exerted at the grousers, unlike in the conventional model.