Your Selections

The Firestone Tire & Rubber Co.
Show Only


File Formats

Content Types









Open-Loop, Fixed-Control Simulation of a Vehicle Undergoing Steering and Acceleration Maneuvers

The Firestone Tire & Rubber Co.-D. R. Tener
Dept. of Mechanical Engineering, The University of Akron-M. L. Chu
Published 1990-09-01 by SAE International in United States
Recent interest in improving vehicle handling performance has concentrated not only upon achieving maximum acceleration or braking ability of the motor vehicle, but also upon maintenance of high lateral stability during acceleration or braking.This study examines the influence of tire traction and vehicle characteristics on the directional behavior of an automobile undergoing maneuvers requiring combined longitudinal and lateral tire forces. The vehicle model considered in this analysis consists of ten degrees of freedom, including wheel rotational dynamics and steering system characteristics. The equations of motion for the sprung and unsprung masses have been derived using Lagrange's special equations for quasi-coordinates. The analysis includes nonlinear tire traction characteristics which expresses the longitudinal and lateral tire shear force components as analytical functions of several parameters. These parameters characterize both tire mechanical properties, and dynamic variables which describe tire/road contact patch kinematics.
Annotation icon

Radial Truck Tire Trends

The Firestone Tire & Rubber Co.-Lloyd C. Cooper
Published 1985-08-01 by SAE International in United States
United States heavy duty radiall truck tire usage has grown to about the same level as bias tire usage. Tubeless construction, low aspect ratio size and retread usages have increased along with the trend to radial construction. Future usage trends are expected to include tires for further fuel economy improvements, lighter weight tires, and tires to help increase vehicle efficiency in areas such as greater trailer volume and better braking life.
Annotation icon

SAE Interlaboratory Test for Rolling Resistance of Passenger Car Tires - Part I: Data Variation Within and Between Laboratories

The Firestone Tire & Rubber Co.-D. J. Schuring
The BFGoodrich Co.-C. A. Brunot
Published 1983-06-06 by SAE International in United States
An interlaboratory test program was carried out by twelve test facilities with the objective to determine the degree of tire rolling resistance loss variations within and between laboratories. The same tires and test procedures were used throughout. Statistical data analysis involving all data as well as various data subgroups suggest that most of today's tire rolling loss test facilities have obtained an excellent level of performance. All measured and analyzed data are tabulated and displaced for each laboratory.
Annotation icon

Computerized Tire Footprint Area Measurements

The Firestone Tire & Rubber Co.-C. E. Prettyman
Published 1981-02-01 by SAE International in United States
A computerized system to automatically measure tire footprint areas has been constructed and used to study the variations in the tire footprint area characteristics as a function of various tire parameters. The individual system components including the optical vidicon, TV monitor, TV control and digitizer, computer, data storage device, printer and plotter are described and their function in the system explained. A flow-chart of the systems computer program shows the methods used to control the test, to collect and store the digitized visual data, to calculate tire footprint length, width, total footprint area, contact area and void area and to report the results. A description of the procedure used to calibrate the system and the various test procedures used to directly or indirectly measure the tire footprint areas are given. Comparisons including test time, test accuracy and test repeatability are made between this system and the traditional methods of measuring tire footprint areas.The results presented in this paper include variations in footprint areas for a radial tire as a function of inflation pressure, tire load,…
Annotation icon

Contained Air Flow in a Radial Tire

The Firestone Tire & Rubber Co.-D. J. Schuring
Aerodynamic Research Dept., Calspan Advanced Technology Center-G. T. Skinner, W. J. Rae
Published 1981-02-01 by SAE International in United States
Internal heat transfer through the tire cavity from the tire to the rim is strongly influenced by the speed distribution of the cavity air. For lack of any experimental data, exploratory tests with a hot-wire anemometer were performed on a radial tire operated at various loads, speeds, and inflation pressures. The measurement technique is described, and some results are presented.Cavity air flow is governed by the peristaltic action of the footprint region; however, it is strongly modified by secondary flows. The general speed distribution is very stable, with a peak at the leading edge of the footprint and a near-zero minimum at the tire top. Peak speeds of about 30% of the tire road speed were measured. These high speeds together with the augmenting effects of secondary flows may produce internal heat transfer coefficients well comparable with those at the outer surface.
Annotation icon

A Review of Scrap Tire Disposal Processes

The Firestone Tire & Rubber Co.-E. L. Kay, J. R. Laman
Published 1979-02-01 by SAE International in United States
This review primarily covers scrap tire disposal processes used, or suggested for use, in the U.S.A.Sufficient statistical data are presented to define the magnitude of the scrap tire disposal problem.The constraints of an ideal solution are presented as a basis for a critical review of current and proposed scrap tire disposal procedures.Our conclusion is that no one scrap tire disposal procedure is so outstanding as to be used exclusively to handle the problem. Geographic location and economics will dictate which scrap tire disposal procedure will be used.
Annotation icon

The Energy Loss of Tires on Twin Rolls, Drum, and Flat Roadway - A Uniform Approach

The Firestone Tire & Rubber Co.-D. J. Schuring
Published 1977-02-01 by SAE International in United States
A general concept of tire energy loss is suggested, in which tire and roadway are considered a system, and tire energy loss is identified as the difference between input and output energies. From this concept, a uniform set of loss equations is derived covering not only the three commonly used test facilities, i.e., twin rolls, drum, and flat roadway, but also the major modes of tire operation including free-rolling, driving and braking. A few test results are discussed.
Annotation icon

Bead Contact Pressure Measurements at the Tire-Rim Interface

The Firestone Tire & Rubber Co.-J. D. Walter
Systems Research Labs-R. K. Kiminecz
Published 1975-02-01 by SAE International in United States
A method has been developed for measuring the normal contact pressure distribution at the interface between a tire and a rim using a miniature magnetostrictive transducer as the load sensor. The transducer itself is a 0.050 in. diameter nickel ferrite toroidal core wrapped with primary (excitation) and secondary (sense) windings. As the core is stressed, the magnetostrictive phenomenon causes an increase in the magnetic flux and a corresponding change in the induced output voltage across the sense windings. This voltage change is signal conditioned to yield a dc voltage output as a function of core stress which is proportional to the bead contact pressure.Bead contact pressures were mapped at the interface between various radial tires and rims under static and dynamic loading conditions. Static pressure distributions obtained for the inflated but otherwise unloaded condition provide a measure of the conformability of the tire to the rim. Dynamic pressure distributions show stress patterns developed under straight-ahead rolling and cornering conditions.With the aid of such bead contact pressure measurements, stress analysis studies of tires and wheels can…
Annotation icon

Tire Conicity and Ply Steer Effects on Vehicle Performance

The Firestone Tire & Rubber Co.-Bruce E. Lindenmuth
Published 1974-02-01 by SAE International in United States
Conicity and ply steer are lateral forces developed by tires whose importance has surfaced with radial tire popularity. Understanding their significance is enhanced by knowing their dependence on measurement and usage parameters and tire construction features.Their effects on vehicle performance are manifested in vehicle pull and vehicle drift or dog tracking. Knowing their individual vehicle performance characteristics offers insight into handling related field-service problems more effectively.
Annotation icon

Effect of Road Surface and Bed Clearance on Truck Tire Noise

The Firestone Tire & Rubber Co.-G. R. Thurman
Published 1974-02-01 by SAE International in United States
The sound level of crossbar-type truck tires was found to be only slightly affected by the texture of the portland concrete road surfaces used. Rib-type tires showed higher noise level on coarse than on smooth surfaces, but the ranking of different tires was unaffected. Clearance of the truck bed above the tire was relatively unimportant. Noise level increased with increase in speed. Sound persistence after truck passby is related to tread design and possibly to the radiation pattern from the road-tire interface.
Annotation icon