No abstract

No abstract

-In an attempt to understand the relationship between quasi-static and dynamic test results, repeatable, dynamic rollover tests were conducted on production vehicles to determine intrusion and intrusion velocities using the Jordan Rollover System (JRS). These tests included complete production vehicles and body bucks at reduced weight, to vary the roof strength-to-weight ratio. Data from these tests are compared with the results of quasi-static roof strength tests measured at greater roll and pitch angles than are used in FMVSS 216. Biomechanical data indicates that serious head, face, neck or thoracic spine injury are a consequence of rapid impacts with significant amplitude. The test data suggests a correlation between quasi-static roof strength and dynamic roof intrusion velocity. Localized failures (buckling and collapse of structural elements that often translate into the roof panel) are a more critical aspect of roof performance than its strength as measured in FMVSS 216.

No abstract

Automobile roof strength is regulated by Federal Motor Vehicle Safety Standard, FMVSS, 216, promulgated in 1971 as a temporary alternative to the dolly rollover test of FMVSS 208. The originally proposed test focused the load on the A-Pillar/Roof Rail/Header intersection and required both sides of the roof to be tested sequentially mimicking the contact sequence in a multiple rollover. The current standard is a less stringent part of the original proposal, which tests the vehicle at a shallower pitch angle with a larger platen and only stresses the first or leading side impact of the vehicle roof. A new fixture has been built that closely duplicates the originally proposed test (NHSB 1971), but with more realistic load application angles that are different on the near and far side of a vehicle during a roll. Tests performed to date illustrate the weakness of current production vehicle roofs.