Implementation of Child Biomechanical Neck Behaviour into the Hybrid III Crash Test Dummy 2008-01-1120

This research focuses on comparing the biomechanical response of the head and neck of the Hybrid III 3-year-old anthropometric test device finite element model and pediatric cadaver data, under flexion-extension bending and axial tensile loading conditions. Previous experimental research characterized the quasi-static biomechanical response of the pediatric cervical spine under flexion-extension bending and tolerance in tensile distraction loading conditions. Significant differences in rotational and linear stiffness were found between the Hybrid III model and the pediatric cadaver data. In this research the biomechanical child cadaver neck response has been implemented into the 3-year-old Hybrid III child dummy FE model. An explicit finite element code (LS-DYNA) and the modified Hybrid III model were used to numerically simulate the previous cadaver tests and validate the altered Hybrid III neck. Subsequent simulation of the child cadaver sled tests were completed with the child biomechanical test results implemented into the Hybrid III. The altered Hybrid III dummy illustrated a significant increase in flexion and distraction of the neck during the simulated sled test and a greater degree of chest deflection. The HIC evaluated using a 36 ms window for the altered Hybrid III dummy was observed to be 268 while the unaltered child dummy observed a HIC value of 194 evaluated using the same 36 ms window. The upper neck resultant forces computed from the simulation from the altered Hybrid III were observed to be 2.3 kN which, based upon the pediatric biomechanical response, would indicate tissue failure in this vicinity of the cervical spine.