Experimental Injury Biomechanics Of The Pediatric Head And Modeling Of Test Equipment

Traumatic brain injury is a leading cause of death in children in road traffic accidents.Single heads were took as samples in main child tests which were regardless of the coupling effect between neck and head.Because of the difficulty of obtaining child cadavers,most biomechanical responses of pediatric heads were got by the model method based on the scaling method.But there are significant differences in anatomical structure and mechanical mechanical properties between child and adult heads.Therefore,it is importance to obtain accurate data to to improve models' accuracy.And it is necessary to prove the set-up efficiency and study the coupling effect between neck and head on responses of the head.This paper presents a set-up for separately hanging the head and torso of pediatric cadavers.The frontal bones of two about 3-year-old specimens were impacted at four impact energy levels.Computed tomography scans identified fractures in orbit regions in one specimen and fractures in the frontal bone and orbit regions in the other specimen.The peak impact forces are 2,023 N and 2,324 N.Values of HIC15 are respectively 197 and 186.Compared with data in the literature,these results are reasonable.And it was found that sample poses had little effect on results.And collision energy,the neck structure and the suspension device could affect test results through the analysis of force on the head.FE set-up models were built and then verification tests were designed and implemented.In simulation and verification tests,the kinematic response of parts of the set-up was consistent,and acceleration curves of the head impactor were well fitted.And these models proved reliable.Head impact test models were established and validated based on this model.A series of single variable simulation tests were carried out based on above experimental variables.Results showed that the effect of experimental variables which included mechanical properties of elastic ropes and springs and head position on results could be ignored,and control variables,impact speed in particular increased as HIC15 values increased.Neck variables,such as stiffness increased as HIC15 values decreased.It showed that set-up was reasonable,but it was necessary to study control variables further.Therefore,whole pediatric cadaver tests were closer to the stress state in head and are significant.