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A series of tests were conducted utilizing a tire test machine built to measure forces during a tire tread separation event. Tires were prepared by cutting between the two steel belts inward from the shoulder area. Cuts were varied in size and location to generate different types of tread separation events (ex: long, short, partial, inboard, and outboard). The tests document the longitudinal and lateral forces generated while the tread is detaching during different types of tread separation events. The results demonstrate that magnitude and duration of forces depend upon the nature of the tread separation event. Additional documentation includes high speed and real time video of the tread separation events to provide insights into tread detachment modes and mechanisms of measured force response.

Temporary-use-only spare tires are common standard equipment on motor vehicles while run-flat tires are offered as standard equipment on some motor vehicles. This paper describes testing on a 1995 GMC Safari all-wheel-drive minivan with a rear Uniroyal Hideaway / Temporary-Use-Only tire and a 1997 Mercury Grand Marquis with a self-supporting run-flat tire manufactured by Bridgestone. The testing included circle turn tests and 180° step steer tests at target speeds of either 30 or 35 miles per hour (low speed J-turn test). Control tests were conducted with standard normally inflated tires. Both the standard tires and run-flat tires were also tested in a modified condition involving the removal of the tread and outer steel belt, simulating a tire which has experienced a complete tread-belt separation.

Effective slack associated with seat belt systems for rollover protection is studied for the purpose of improving or anticipating improvements to a motor vehicle rollover protection system. A test method and test devices were constructed to study and develop objective understandings of the effects of motor vehicle seat and seat belt characteristics on effective slack. The test devices and test method were proved in two separate motor vehicles with differing seat belt systems. Results demonstrated that effective slack as a conceptual equivalent to a seat belt webbing length could be repeatable and objectively determined for the systems tested. Determining a seat belt system's effective slack is useful for the purpose of comparing experimental restraints and experimental restraint testing to motor vehicle restraint design and performance.

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.

Using analysis of a mini-van test vehicle’s static load conditions as a guide, four different vehicle loading situation were constructed. The loading situations represent the corners of the vehicle’s center of gravity position envelope. For the testing described in this paper a single vehicle under conditions of varied load was subjected to a series of test maneuvers designed to elicit objective measure and comparison of vehicle steady-state and transient response. The purpose of this paper is to describe the test method and present the results of handling testing and limit stability testing of a 1991 Ford Aerostar mini-van/extended van under four different loading conditions. Differences observed in the plotted results of vehicle steady state response for different load condition are detectable, but small. The test results demonstrate differences in vehicle transient response for different loading configuration.

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.

Tests were conducted to evaluate the effects of the tire-induced vibration caused by a tread separating rear tire on the handling characteristics of a 1996 four-door two-wheel drive Ford Explorer. The first test series consisted of a laboratory test utilizing a 36-inch diameter single roller dynamometer driven by the rear wheels of the Explorer. The right rear tire was modified to generate the vibration disturbance that results from a separating tire. This was accomplished by vulcanizing sections of retread to the prepared surface of the tire. Either one or two tread sections covering 1/8, 1/4, or 1/2 of the circumference of the tire were evaluated. The results demonstrated that a tire modified with two bonded-on tread sections driven at half speed replicated axle tramp characteristics of a modified tire with a single bonded-on tread section at the peak axle tramp speed.

To date, the flammability of common automotive fluids under real-world conditions has not been well characterized for general use in the automotive community. This paper presents the results of a research program aimed at providing a greater understanding of the potential fire hazards of common fluids carried on board today's vehicles. A literature review was conducted to define the ignition properties of common automotive fluids as determined very precisely in the lab environment. A test program was then established to gain insight into the ignition properties of common automotive fluids under some real-world conditions. Automotive engine and exhaust components were used to create a test mechanism which realistically represented the environment, temperatures, and surfaces to which vehicle fluids may be subjected The reported laboratory results are compared to the test data. Tests were conducted on twelve fluids with and without ignition sources present.