Tire Cleat Impact and Force Transmission: Modeling Based on FTIRE and Correlation to Experimental Data

The force transmission from the road surface to the spindle due to road disturbances is a significant factor in ride comfort. In this study the force transmission of tires rolling over cleats is studied using both a new numerical tire model, FTIRE, and measured data. FTIRE is a time-integrated physics based tire model with a flexible belt.

The predicted and measured tire force response due to cleat impact is determined at different rolling speeds, cleat shapes, tire constructions and loading parameters. Excellent correlation between model and experimental data is achieved for all test parameters.

Several observations regarding the force transmission are made with respect to the aforementioned test parameters. These observations are also related to dynamic tire properties. It is observed that a “quiet speed” exists, at which the tire vertical response is significantly reduced. The reason for this “quiet speed” and its relationship to the test parameters is discussed