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The purpose of this study was to reconstruct the accident situation of a Golf-Cart with three persons in it. The cart was designed to carry two persons and their golf bags, someone had fixed an add-on cab. Tilt-table testing was carried out to estimate the rollover threshold and to measure the center-of-gravity location of the vehicle, which was used to do preliminary stability analysis for different loading conditions. Tests were carried out with and without the add-on cab. The add-on cab deteriorated the rollover characteristics by raising the center-of-gravity height, while the presence of an additional rider on the rear-left wheel arch, biased the load distribution. These two effects resulted in reducing the rollover threshold. Generally, tilt-table test results overestimates the rollover threshold, so there is a good possibility in real world situations the acceleration experienced by the vehicle during steady-turn maneuvers on an even surface could lead to rollover.

Simulation studies are widespread in vehicle handling/dynamics analysis. Over the years, many researchers have developed vehicle models ranging from a simple half-car model to a very detailed model. There is a general perception that a detailed model is guaranteed to yield a better result; yet it should be noted there are no recommended or standard procedures to measure vehicle parameters required for simulation studies. Recent studies have revealed that different measurement procedures could lead to significant differences in the measured parameters. This paper discusses the issue of model complexity in the context of available input parameters, especially tire data. Also, for vehicular application, the lumped parameter modeling approach and multi-body formulation approach advantages and disadvantages are discussed.

A hybrid approach has been developed to determine the dynamic vehicle rollover threshold. The approach uses a roll-plane vehicle model and a simulation based on the testing that was carried out at low speeds, where lateral acceleration are measured. Then, curve fitting techniques are used to extrapolate for the threshold values of lateral acceleration and forward velocity. This approach was validated using lane-change maneuver test data and a good correlation was obtained. Further, this approach is well suited as an objective test procedure to determine the rollover threshold as only lateral accelerations need to be measured.

It is a common practice throughout the vehicle manufacturing industry to perform full-scale durability tests on new model vehicles. Durability tests are initially conducted on prototype vehicles for design validation and then later, on production units to ensure it's structural integrity and to obtain data that can be used for future design improvements. In the case of commercial and transit vehicles, this information can be particularly useful for projecting it's minimum expected service life. Vehicle durability testing typically involves subjecting the vehicle to stress inducing inputs similar to those that would normally be encountered in an expected service environment. These inputs are applied to the vehicle at an accelerated rate to reduce the total testing time. Vehicle inputs for a durability test are imparted through either a test track or a mechanical road simulators such as four-post shakers. Each method has its advantages and limitations.