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In the simulation of the dynamic response of a vehicle, the accuracy of the predictions strongly depends on the tire properties. Since the physics of tire force generation is highly nonlinear and complex, semi-empirical models are used, which are mathematically curve fitted to experimental data. Although this approach yields realistic tire behavior, it requires many experimental coefficients. Even though tire forces generated by a real tire are nonlinear, there is a linear region where the slip and slip angle are low. Most normal driving is done in this region. This paper will present a new analytical tire model capable of simulating pure cornering, pure braking, and combined braking/cornering in this region. The dynamic properties of the tire are analytically derived as functions of the slip, slip angle, normal force, and road friction coefficient.

This paper proposes an effective nonlinear bicycle model including longitudinal, lateral, and yaw motions of a vehicle. This bicycle model uses a simplified piece-wise linear tire model and tire force tuning algorithm to produce closely matching vehicle trajectory compared to real vehicle for wide vehicle operation ranges. A simplified piece-wise tire model that well represents nonlinear tire forces was developed. The key parameters of this model can be chosen from measured tire forces. For the effects of dynamic load transfer due to sharp vehicle maneuvers, a tire force tuning algorithm that dynamically adjusts tire forces of the bicycle model based on measured vehicle lateral acceleration is proposed. Responses of the proposed bicycle model have been compared with commercial vehicle dynamics model (CarSim) through simulation in various vehicle maneuvers (ramp steer, sine-with-dwell).

The ever increasing competition of present day has made the timely and cost effective development of high-quality, precision products, of great importance to various industries. Hence, applications of computer simulation have radically increased in recent years. This paper presents a development of vehicle dynamics simulation and animation environment using Matlab-Virtual Reality Toolbox which can be used for the analysis of vehicle performance. This simulation tool consists of three modules (simulator, preprocessor, and animator) and can provide comprehensive responses and animation of different vehicle maneuvers.

The sophistication of all-wheel-drive technology is approaching the point where the drive torque to each wheel can be independently controlled. This potentially offers vehicle handling enhancements similar to those provided by Dynamic Stability Control, but without the inevitable reduction in vehicle acceleration. Independent control of all-wheel-drive torque distribution would therefore be especially beneficial under acceleration close to the limit of stability. A vehicle model of a typical sports sedan was developed in Simulink, with fully independent control of torque distribution. Box-Behnken experimental design was employed to determine which torque distribution parameters have the greatest impact on the vehicle course and acceleration. A proportional-integral control strategy was implemented, applying yaw rate feedback to vary the front-rear torque distribution, and lateral acceleration feedback to adjust the left-right distribution.

Yaw and roll stability limits are derived for three quasi-static roll plane models: rigid vehicle, suspended vehicle, and compliant tire vehicle. A generalized stability equation is identified that fits the stability limits for each model. This generalized stability equation leads to the definition of two new parameters referred to as the generalized superelevation and generalized center of gravity height. These parameters are shown to be physically meaningful. The use of linearizing assumptions is minimized and road superelevation is included, resulting in a more complete equation for each stability limit. Each derived stability limit is then compared and contrasted to the typical representations found in the literature.