Nonlinear Vehicle Performance Simulation with Test Correlation and Sensitivity Analysis 960521

A dynamic vehicle simulation has been developed to predict straight-line acceleration of a traction limited, manual transmission vehicle that is capable of high rates of tire slip. The simulation incorporates an empirical non-linear curve which predicts tire friction as a function of tire slip. A vehicle is tested to compare and correlate simulated performance to actual performance, and the simulation is shown to be accurate. The model is then exercised to predict the impact of vehicle design on performance. All major systems of the vehicle are extensively studied, including vehicle weight, center of gravity location, aerodynamic drag coefficient, and drivetrain ratios, inertias, and efficiencies. These studies indicate that the most influential parameters on 0-60 MPH times (other than horsepower) are tire friction, rear weight bias, engine inertia, and total vehicle weight. Design parameters with little influence on 0-60 performance include axle ratio, wheel inertia, and aerodynamic drag. Results are similar for ¼-mile times. These results are quantified in the paper.