Measurement of the three-directional contact force using a smart tire with a force sensor

While designing tire performance, understanding the relationship between the tire belt or tread rubber and the road surface is crucial, as represented by the cornering performance and wear characteristics. To survey this relationship, the force generated when a tire moves over a force sensor installed on the drum side of a tire drum tester or a sheet-type sensor installed on the road surface is measured to estimate the contact pressure distribution. The former method does not allow measurements on a flat surface, whereas the latter uses an actual vehicle; thus, obtaining stable data is challenging. In this study, we measured the triaxial forces acting on the tread block of a tire with a slip angle applied to the tire alone and discussed the characteristics of these forces. In the proposed measurement method, a tire tread block is machined, and a small triaxial force sensor is embedded. This method enables measuring the forces between the tire belt and the road surface. Finally, the force generated via the tire/road interaction on the tread block was measured using a flat-belt tester. The characteristics of the forces generated by the tread block are reported based on the obtained results.