Development of a mathematical tool to measure crash severity in frontal impacts


Himmetoğlu S., Dugan G.

26th International Scientific Conference Transport Means 2022, Kaunas, Lithuania, 5 - 07 October 2022, pp.254-259 identifier

  • Publication Type: Conference Paper / Full Text
  • City: Kaunas
  • Country: Lithuania
  • Page Numbers: pp.254-259
  • Hacettepe University Affiliated: Yes

Abstract

This study presents a 4 degree-of-freedom spring-mass-damper model based on the well-known viscous thorax model by Lobdell. The developed model, which includes a seatbelt model with load limiter and belt slack, is aimed at detecting the severity of various crash pulses observed in frontal impacts. For this purpose, a total of 22 different crash pulses with different shapes were extracted from the National Highway Traffic Safety Administration (NHTSA) database regarding full-width rigid barrier (FWRB) frontal impact tests at an impact speed of 56 km/h under the New Car Assessment Program (NCAP) comprising SUVs, light trucks, vans and passenger cars. The results indicate that for a given load limiter setting, maximum chest deformation and largest thorax acceleration are not affected by the variation in the crash pulses whereas maximum chest travel and maximum chest velocity with respect to vehicle show high sensitivity to maximum moving average accelerations of the crash pulses. Maximum chest deformation and largest thorax acceleration are greatly affected by the variation of the load limiter value. Maximum moving average acceleration with a time window of 50 ms shows the best correlation with chest velocity and chest travel which can be used as metrics for crash severity and structural performance of cars. It has been observed that sustained large accelerations for a time period longer than 30 ms produce severe pulses.