Computational modeling and analysis of a passenger car frontal impact per new FMVSS offset oblique and small overlap tests

Abstract

Crash tests play a vital role in the design and development of new vehicles to ensure customer safety. The results obtained from the test programs such as the ones from the National Highway Traffic Safety Administration (NHTSA) are useful for further development of vehicles pertaining to consumer safety. The new and latest oblique offset and small overlap crash tests represent more realistic configurations of the frontal car impact accidents compared to earlier version of standards. In this study, finite element (FE) models of a family sedan car impact surroundings are utilized to reconstruct the tests. The objective of this study is to utilize computational modeling and analysis techniques to assess the performance of a typical sedan car per new small overlap frontal crash test and oblique offset tests, and to compare the results with the original rigid barrier impact crash test in terms of physical intrusion of the vehicle body parts and examining the corresponding potential injuries to occupants. The validation of the models are performed to ensure model accuracy and to check for any abnormalities in the FE models. In this research, the vehicle-to-barrier and vice versa models are simulated using the LS-DYNA nonlinear code. The full frontal impact crash tests are simulated according to the NCAP protocol. The oblique offset and small offset frontal impact tests are then investigated as they represent real-world scenarios better. The data obtained from the intrusions on the vehicle's A- and B- pillars, firewall, toe pan, knee bolster and steering column are analyzed. The results from different scenarios obtained are then compared in terms of intrusion and acceleration inside the car and the analysis of intrusion and occupant injury. It is observed that the small offset crash test adds more challenge not only to the structure of the vehicle but also to the design of seat belts and airbags. This study indicates that the compliance with the offset oblique and small offset frontal impact tests provide the best occupant protection where the occupant sustains maximum G- force especially in terms of head impact protection to the car's A-pillar.