Development of new dynamic tire model for improved vehicle dynamics simulation.

摘要

The simulation of tire output responses in some existing tire models is evaluated for their ability to accurately describe tire force and moment generation using experimental tire data. The study includes the characterization of quasi-static and dynamic behavior of tire output responses in steering, braking/driving, and combined steering and braking/driving maneuvers. From this evaluation, new dynamic tire model is developed to enhance vehicle dynamic simulation in quasi-static and dynamic maneuvers. The new model enhances the predictability of pneumatic tires in the braking/driving as well as steering mode.; Existing tire models do not consider dynamic characteristics of all tire output responses. Current models developed in the consideration of tire dynamics are limited only to the tire lateral force, and are not accurate enough to describe the dynamic characteristics of tire behavior in severe maneuvers (crash-avoidance type maneuvers). However, the characterization of the dynamic behavior of the all tire output responses is completely treated and is implemented in the new dynamic tire model.; The new dynamic tire model is based on the lumped model of tire contact patch. On the Basis of the lumped model, the differential equations about the longitudinal and lateral displacements are derived and transformed into difference equations for simulation purposes. The estimation of unknown parameters existing in the derived differential equations is executed and characterized in the function of speed and normal load. Using the difference equation and estimated parameters, the evaluation of the performance of the new model in the prediction of tire output responses to quasi-static and dynamic inputs is presented.; The application of pulse input techniques is studied to obtain valid frequency responses of tire output responses. Pulse steering tests and discrete frequency tests are executed to obtain frequency responses of the tire output responses and to be compared with each other in various speeds and normal loads. The pulse input technique is a good alternative method to the expensive and time-consuming discrete frequency tests.