RESEARCH - Tires

Extracting Tire Model Parameters from Test Data
SAE Paper No. 2006-01-1399 Authors: Wesley D. Grimes, Jonathan A. Balasa, Eric J. Hunter, and Thomas Vadnais

Computer models used to study crashes require information to describe the vehicles. Information such as weight, length, wheelbase, tire locations, crush stiffness, tire parameters, etc. all require a reliable source. Usually the tire parameters are difficult to obtain. Analysts will routinely use default or "typical" values. In 1999, Engineering Dynamics Corp. (EDC) attempted to address this issue, with support from many in the field of crash reconstruction, by conducting tire tests. The resulting tire test data will be used to study motor vehicle performance. The computer simulations in use today require information about tire properties or lookup tables that must be extracted from raw collected data. This paper presents a basic overview of the tire test data and a technique for extracting the required tire parameters for use in computer simulation modeling.

Extracting Tire Model Parameters From Test Data
EDC WP# 2001-4 Authors: Wesley D. Grimes, P.E. and Eric Hunter

Computer models used to study crashes require data describing the vehicles. Data such as weight, length, wheelbase, tire locations, crush stiffness, tire parameters, etc. all require some source of information. Usually the tire parameters are difficult to obtain and analysts will routinely use default or "typical" values. Engineering Dynamics Corp. (EDC), with support from many in the field of crash reconstruction, conducted a tire test series in 1999 to obtain tire data that will be used in studying motor vehicle performance. The computer simulations in use today require some type of tire data coefficients or lookup tables that must be extracted from the raw collected data. This paper presents a basic overview of the tire test data and presents a technique for extracting the required tire parameters for use in computer simulation modeling.

Properties of Passenger Car Tires With Tread Detachment
SAE Paper No. 2000-01-0697 Authors: Mark W. Arndt, Michael Thorne, and Charles P. Dickerson

A series of tire property tests have been performed at CALSPAN on the flat bed tire test machine. The tires used in the testing were inflated tires with the tread removed. Identical make/model/size tires in normal (tread not removed) condition were also tested. Three passenger car tires and one truck tire were tested. The purpose of this paper is to present comparative results of the testing and data analysis. The test results objectively demonstrate substantial differences in cornering properties. Grouping all tires together, the measured cornering stiffness of a modified tire was reduced on average to 36.1 percent of the normal tire measured properties (ranging from 24.1 to 49.4 percent; standard deviation was 7.7 percent). Overall the character of the modified tire cornering stiffness plots and other modified tire properties were demonstrated to be markedly changed.

Vehicle Handling with Tire Tread Separation
SAE Paper No. 1999-01-0120 and 1999-01-0450 Authors: Charles P. Dickerson, Mark W. Arndt, and Stephen M. Arndt

Catastrophic and sudden tire tread separation is an event that drivers of motor vehicles may encounter and, in some instances, is implicated as the cause of motor vehicle crashes and related injury or property damage. In an effort to understand how tire tread separation affects vehicle handling, a series of tread separation handling test programs were conducted. In each tread separation test program a sport utility vehicle was instrumented and equipped with steel belted radial tires that were modified to emulate tread separation between the inner and outer steel belts. The test vehicle was then subjected to a variety of open and closed loop handling test maneuvers. This paper presents the data and analysis from these tests. The research demonstrates through controlled experiments that a tire tread separation has an effect on the vehicle's fundamental handling characteristics. It also demonstrates that the effect depends on the position of the compromised tire on the vehicle.

3-Dimensional Simulation of Vehicle Response to Tire Blow-outs
SAE Paper No. 980221 Authors: William Blythe, Terry D. Day, and Wesley D. Grimes

Sudden tire deflation, or blow-out, is sometimes cited as the cause of a crash. Safety researchers have previously attempted to study the loss of vehicle control resulting from a blow-out with some success using computer simulation. However, the simplified models used in these studies did little to expose the true transient nature of the handling problem created by a blown tire. New developments in vehicle simulation technology have made possible the detailed analysis of transient vehicle behavior during and after a blow-out. This paper presents the results of an experimental blow-out study with a comparison to computer simulations. In the experiments, a vehicle was driven under steady state conditions and a blowout was induced at the right rear tire. Various driver steering and braking inputs were attempted, and the vehicle response was recorded. These events were then simulated using EDVSM. A comparison between experimental and simulated results is presented. The research was extended by simulating blow-outs at other wheel locations and observing how various driver inputs affect the vehicle's response.