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The analysis and modeling of vehicle crush in accident reconstruction has traditionally been based upon the use of linear, crush-based, stiffness coefficients. Recent advances have allowed for the calculation and implementation of non-linear crush coefficients in the accident reconstruction software Human-Vehicle-Environment (HVE) by Engineering Dynamics Corporation (EDC). HVE contains the collision algorithm called DyMESH (DYnamic MEchanical SHell), which is capable of using the non-linear coefficients. These non-linear coefficients have shown to increase the accuracy of a predicted crash pulse. Published research on non-linear crush coefficients for the use in HVE has been limited to frontal impacts. Calculating side stiffness coefficients is more complex since most side impact crash tests involve two vehicles that can crush and absorb impact energy.

The analysis and modeling of vehicle crush in accident reconstruction has traditionally been based upon the use of linear crush-based, stiffness coefficients. Engineering Dynamics Corporation (EDC) created the accident reconstruction software Human-Vehicle-Environment (HVE) which contains the collision algorithm called DyMESH (DYnamic MEchanical SHell) which is capable of utilizing a non-linear stiffness coefficient model. The objective of this research was to develop an improved methodology for the calculation of non-linear stiffness coefficients. Stiffness coefficients are used to represent the relationship between the impact force on a vehicle and the resulting vehicle crush. The method explored in the present research was focused on developing vehicle specific, non-linear stiffness coefficients (Pressure Model) based upon frontal crash tests into a fixed, rigid barrier equipped with load cells.

Collision data stored in the Airbag Control Module (ACM) of some Chrysler vehicles has become available to accident investigators through the Bosch Crash Data Retrieval (CDR) system, beginning with the 2005 model year. An event data recorder (EDR) that can record pre-deployment vehicle speed and other parameters such as brake pedal application and throttle application is incorporated into the ACM, or Occupant Restraint Controller (ORC) using Chrysler terminology. The accuracy of this data under different driving conditions has not been extensively tested and reported. The primary purpose of this paper is to evaluate the accuracy of the data recorded in the Chrysler ACM under test conditions. Establishing the reliability of this information is important, if it is to be relied upon by the investigator. These results can be used to quantify the accuracy of ACM reported pre-crash data for use in engineering analysis of automobile crashes.