Occupant Dynamics in Rollover Crashes: Influence of Roof Deformation and Seat Belt Performance on Probable Spinal Column Injury

Abstract

Abstract-Motor vehicle crashes are the leading cause of death in the United States for people ages 3-33, and rollover crashes have a higher fatality rate than any other crash mode. At the request and under the sponsorship of Ford Motor Company, Autoliv conducted a series of dynamic rollover tests on Ford Explorer sport utility vehicles (SUV) during 1998 and 1999. Data from those tests were made available to the public and were analyzed in this study to investigate the magnitude of and the temporal relationship between roof deformation, lap-shoulder seat belt loads, and restrained anthropometric test dummy (ATD) neck loads.During each of the three FMVSS 208 dolly rollover tests of Ford Explorer SUVs, the far-side, passenger ATDs exhibited peak neck compression and flexion loads, which indicated a probable spinal column injury in all three tests. In those same tests, the near-side, driver ATD neck loads never predicted a potential injury. In all three tests, objective roof/ pillar deformation occurred prior to the occurrence of peak neck loads (F z , M y ) for far-side, passenger ATDs, and peak neck loads were predictive of probable spinal column injury. The production lap and shoulder seat belts in the SUVs, which restrained both driver and passenger ATDs, consistently allowed ATD head contact with the roof while the roof was contacting the ground during this 1000 ms test series. Local peak neck forces and moments were noted each time the far-side, passenger ATD head contacted (''dived into'') the roof while the roof was in contact with the ground; however, the magnitude of these local peaks was only 2-13% of peak neck loads in all three tests. ''Diving-type'' neck loads were not predictive of injury for either driver or passenger ATD in any of the three tests.

Reconstruction of a Rollover Crash for Thoracic Injury Etiology Investigation

“…This resulted in the thorax pivoting forwards and pressing against the locked seatbelt sash, thus resulting in the observed loads. This observed axial force is similar to the sash belt axial forces observed in previous studies [56].…”

“…The maximum observed axial force from this study are noted to be approximately three times higher than those measured in previous studies [56]. These observed higher axial belt forces is a reflection of the ATD pelvis moving upwards (i.e., away from the seat cushion) and towards the door and is restrained by the lap belt.…”

Damages of locomotor apparatus in children as a result of road accidents

“…Именно у детей и подростков в возрасте до 15 лет автодорожная травма яв ляется ведущей причиной летальности [10]. В Соединенных Штатах дорожно транспортные происшествия также представляют основную причину смерти в категории людей в возрасте от 3 до 33 лет [9]. По мнению некоторых авто ров, в 86,4 % случаях автомобильные травмы имеют сочетанный характер.…”

Cervical spine injuries and flexibilities following axial impact with lateral eccentricity

“…Only 3 % of the injuries reported by Allen et al [7] were due to lateral bending and these relatively uncommon injuries are well-recognized in clinical practice [3,4,9,10]. However, biomechanical experiments [11][12][13] and reconstructions of rollover motor vehicle collisions [14,15], during which occupants effectively dive into the ground, indicate that lateral forces are present in these real-world head-first impacts resulting primarily in asymmetric injuries [16]. We are presently unable to quantify the incidence of injuries resulting from such loading scenarios, as current classification systems do not include such a mechanism.…”