Modeling of Dynamic Characteristics of Tire Output Responses to Concurrent Inputs

This paper discusses the development of a tire model for predicting the dynamic characteristics of major tire output responses to concurrent inputs for use in the simulation of vehicle dynamics. In this dynamic tire model, the contact patch of the tire is lumped into a number of elements to study the dynamic behavior of the displacement of the tire contact patch in the lateral and longitudinal directions. For each displacement, a differential equation governing the dynamic behavior of the displacement to the dynamic concurrent inputs is derived. Based on the differential equations for the lateral and longitudinal displacement, difference equations can be obtained for the purpose of simulating tire output responses. Unknown system parameters, in the difference equations, such as mass, damping and stiffness are estimated using the differential equations and experimental data. This model is validated by comparing simulation results and experimental data for selected pure steering and combined steering and braking maneuvers.