ABSTRACT

In this work a Tire State Estimator (TSE) is developed and validated using data from a tri-axial accelerometer, installed at the inner liner of the tire. The Flexible Ring Tire (FRT) model is proposed to calculate the tire deformation. For a rolling tire, this deformation is transformed into tangential and radial accelerations of a point on the inner liner. The results of this model show close correspondence to the experimental data. The FRT model is implemented in the observer of the TSE to estimate the longitudinal and vertical tire forces. Besides the observer, the TSE comprises a peak synchronization (PS) algorithm. Experiments show that the TSE provides accurate estimation of longitudinal and vertical tire forces, even for severe braking conditions. In addition, it shows robustness and fast convergence for large initial estimation errors. Finally, this concept of model-based tire force estimation results in a small estimation time delay.