A 3D Semi-Empirical On-Road Transient Tire Model

To realistically predict the dynamics of a vehicle, the forces and moments in the contact patch must be accurately computed. A two-dimensional semi-empirical transient tire model was previously developed in the Advanced Vehicle Dynamics Lab (AVDL) at Virginia Tech, and extended the capabilities of the steady-state tire model also developed at AVDL. In this paper, a three-dimensional semi-empirical transient tire model is presented. The tire structure is modeled by an elastic ring supported on a spring and damper system. The elastic ring represents the belt ring and the spring and damper system represents the sidewall and the tread element. The analysis of the deformation of the tire structure with camber angle is performed on a flat surface to obtain the geometry of the contact patch and the normal pressure distribution. The forces and the moments are formulated using empirical data and based on theoretical mechanics. Illustrative simulations were performed for two scenarios: a driving/braking maneuver and a lane changing maneuver. The simulation results were compared with the 2D semi-empirical transient tire model results and with the steady-state tire model results and validated based on available data from the literature.