A predicted tire model for combined tire cornering and braking shear forces based on the slip direction

The longitudinal force and lateral force are often exist simultaneously in the tire contact patch, such as steering and braking at the same time. Since the 1930´s, many models have been presented for use in describing the tire forces under this condition, however, these models often need plenty of elaborate testing of combinations of lateral and longitudinal forces which is expensive and difficult. On the basis of the simplified theoretical tire model, a predicted tire model based on slip direction is presented in this paper. This model can predict all tire forces at any cornering/braking combination, and enrich the UniTire tire model about the prediction for tire mechanics characteristics under combined slip mode. The prediction results are verified by tire test data, which show that the tire model has good prediction capability with high accuracy.