Comparison of chest injury measures of hybrid III dummy

Abstract

ABSTRACTThe chest deflection and chest acceleration (3 ms) have been used as chest injury measures of Hybrid III dummy in frontal crash tests. In this research, the relationship between two chest injury measures was investigated based on finite element analysis of Hybrid III in a frontal impact. The equation of motion of the chest was established using the external (seatbelt force and airbag contact force) and internal forces (neck, shoulder joint, lumbar spine force) that are exert on the chest. Based on this formula, the mechanism of the chest acceleration that was generated can be examined with time. The chest deflection is related to the external forces (seatbelt and airbag force), and the chest acceleration is related to the external and internal forces. The influence that the restraint conditions (seatbelt path and force limiter) has on the chest acceleration and chest deflection was also investigated. The seatbelt path affected the rib cage deformation mode and the chest sternum deflection, but it has little effect of on the chest acceleration. Lowering the seatbelt force limiter value also reduced the chest deflection substantially, but it did not show any clear relationship with the chest acceleration since the kinematics and the internal forces of the Hybrid III dummy changed with varying force limiter values.