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Past rollover condition testing reported by the author utilized experimental seat belts, a rigid seat and a sitting pelvis Hybrid III mannequin or volunteer to observe dynamic vertical excursion. Other testing in a rollover condition utilized a rigid mannequin molded from a Hybrid III, sitting in a production vehicle restraint system. Application of rigid device in the test allows for simplification of the problem under study, yet limitations in the interpretation of the results. A third test program was conducted combining the rigid device of prior testing into one test, thereby allowing further scientific inference as to the affect of the seat belt restraint system in rollover conditions. Results show that an important factor in the extent of occupant vertical excursion is the kinematics and compliance of the occupant.

A series of controlled experimental programs were conducted for the purpose of improving the motor vehicle rollover protection system. Test results reported in this paper have been previously presented in SAE Paper No.980213 [1]. Experiments tested lap belt restraints utilizing a variety of lap belt geometric and webbing slack conditions. Tests utilized in the series include dynamic and static tests and the use of test mannequins and human volunteers. In the first test program, utilizing a rigid seat, human volunteers were subjected to minus 1.0 Gz acceleration and a 95th percentile Hybrid III mannequin was subjected to minus 5.0 Gz acceleration for a variety of lap belt conditions. A second program utilized a rigid mannequin in production vehicle seats for the purpose of measuring and comparing seat belt system effective slack. Finally, the rigid mannequin from the second test and the rigid seat and lap belts from the first test were brought together and tested.

Outriggers are devices that arrest vehicle rollover during handling test maneuvers to protect the test vehicle and/or test driver. Validity of data in these tests has been questioned because the effect outriggers have on vehicle dynamics is not well understood. This research quantifies changes in handling characteristics with outriggers attached to a test vehicle. Three outrigger systems of different masses were developed and tested through various limit and sub-limit handling maneuvers. Analysis of the data generated during testing indicates improvements necessary for future outrigger designs leading to better understanding of vehicle dynamics and potentially reduced injuries from rollovers.

A controlled experimental program was conducted to determine the response of humans and a human surrogate with experimental lap belt restraints in -Gz acceleration environments. In the program, lap belt anchorage position (belt angle) and belt tension/slack were varied. Human volunteers were subjected to a static -1.0 Gz acceleration for each restraint configuration. A 95th percentile male Hybrid Ill dummy was subjected to a nominal 4.25 m/s (9.5 mph), -5 Gz impact while restrained by each restraint configuration. For the -Gz acceleration, significant changes in occupant head excursion were observed with varied lap belt configurations. In general, less pre-crash belt slack and higher lap belt angles produced significant reductions in occupant vertical excursions. This research provides data for use in evaluating or developing occupant survivability systems for rollover crash environments.

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.