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Inflation pressure affects every aspect of tire performance. Most tire models, including the Radt/Milliken Nondimensional Tire Model, are restricted to modeling a single inflation pressure at a time. This is a reasonable limitation, in that the Nondimensional model forms an input/output relationship between tire operating conditions and force & moment outputs. Traditional operating conditions are normal load, slip angle, inclination angle, slip ratio and road surface friction coefficient. Tire pressure is more like a tire parameter than a tire operating condition. Since the Nondimensional Tire Model is semi-empirical it does not specifically deal with tire parameters like sidewall height or tread compound. Still, tire pressure is the easiest tire parameter to change, and as the air temperature within the tire varies during use so does the inflation pressure. Thus, it is desirable to incorporate inflation pressure into the Nondimensional Tire Model as an input.

The Formula SAE Tire Test Consortium (FSAE TTC) was established to provide high quality tire data to participating FSAE teams for use in the design and setup of their racecars. Currently, data on ten different constructions of tires has been measured at Calspan's Tire Research Facility and distributed to all consortium members. In this paper we review the history of the FSAE TTC-the inception, organization and continuing operation of this all-volunteer effort. Details of tire testing will be explored, including the many options and constraints considered while designing the tire test matrix. Finally, a review of the measured data is provided. This includes a description of all the output channels and an overview of ways in which FSAE teams can make use of the data.

The Nondimensional Tire Model is based on the idea of data compression to load-independent curves. Through the use of appropriate transforms, tire data can be manipulated such that, when plotted in nondimensional coordinates, all data falls on a single curve. This leads to a highly efficient and mathematically consistent tire model. In the past, data for slip angle and slip ratio has been averaged across positive and negative values for use with the transforms. In this paper, techniques to handle tire asymmetries in lateral and longitudinal force are presented. This is an important advance, since in passenger cars driving/braking data is almost always asymmetric and, depending on tire construction, lateral force data may follow likewise. In addition, this paper is the first to explore the inclusion of inflation pressure as an operating variable in the Nondimensional Tire Theory.

Written for the engineer as well as the race car enthusiast and students, this is a companion workbook to the original classic book, Race Car Vehicle Dynamics, and includes: Detailed worked solutions to all of the problems Problems for every chapter in Race Car Vehicle Dynamics, including many new problems The Race Car Vehicle Dynamics Program Suite (for Windows) with accompanying exercises Experiments to try with your own vehicle Educational appendix with additional references and course outlines Over 90 figures and graphs This workbook is widely used as a college textbook and has been an SAE International best seller since it's introduction in 1995. Buy the set and save! Race Car Vehicle Dynamics

This set includes: Race Car Vehicle Dynamics, Race Car Vehicle Dynamics - Problems, Answers and Experiments Purchase both the book and the workbook as a set and save!

This paper contains an analysis and a related numerical method for finding the movement of a wheel mounted on a double A-Arm suspension. The method is based on the use of Euler orientation variables similar to those which specify aircraft orientations in flight-dynamics studies.

In this paper, we present an approach to the optimization of a racecar using vehicle dynamics simulation in a parallel-computing environment. The use of vehicle dynamics simulations in the automotive and auto racing industries is widespread. Complex vehicle simulations can include hundreds of parameters and be very computationally expensive to perform. This limits the number of design configurations that can be considered within a reasonable time, preventing thorough exploration of the design space. It also limits the usefulness of these simulations during the course of a race weekend when time is of the essence. In this paper, we present results from work to overcome this problem. Our results focus on determining the Pareto optimal designs for a vehicle model with three design variables running simulated races around corners of different radii.

Some fundamentals of barrier placement are derived in this paper and the results are analyzed. While no ideal barrier distance from the racing line can be found for every scenario, each case has a single, worst distance which maximizes impact severity as measured by the vehicle's velocity component normal to the barrier. The ramifications of placing a barrier beyond this critical distance or between the critical distance and the racing groove are examined. Ideas for extending this research are also provided.

Milliken Research Associates has developed a new simulation tool, named Vehicle Dynamics Simulation-Matlab/Simulink (VD-M/S). Produced for the government's Variable Dynamic Testbed Vehicle (VDTV), VD-M/S is an 18 degree-of-freedom simulation programmed in the Matlab/Simulink environment. It contains a detailed non-linear tire model, kinematic and compliance effects, aerodynamic loadings, etc. as do MRA's other simulation programs. Unique to VD-M/S is its development from Day One as a simulation catered to the inclusion and exploration of active systems within the vehicle.