Research On The Injury Risk Of Child Occupant In Vehicle Offset Impact

In recent years, children occupants injury became one of the most important research in automotive crash areas, caused by the frequency of road accidents. Frontal100% overlap impact and offset impact are currently the main form of impact. The resarech of domestic child restraint system started late, the imperfection of the relevant rules and the poor quality of child restraint system directly affect the safety of children occupant. Therefore, in order to improve our children occupant's safety, the resarech of the safety of the design of child restraint systems and children injury protection under frontal 100% overlap impact and offset impact are of great significance.Based on the ECE R44 regulation, establishing the finite element model of sled in frontal full overlap impact with 3-year-old dummy. the vadlidity of the model was verified by the the kinetics response and injury datas of test. And based on the verified model, by the the improvments of structure and using orthogonal experimental design to select parameters which were the influences of the seatbelt guide ring positions, the seat skeleton thickness and the friction coefficient between child and five-point harness, the optimization results show that the head maximum displacement reduces from 1.5% higher than the regulation threshold to 15% lower than the threshold. And dummy's injury parameters which were HIC, the resultant acceleration of chest and the vertical acceleration of chest were lower than the thresholds. The resarech method provides some guidance for the design of child restraint systems in the future.Moreover, the question of child occupant safety largely comes from frontal100% overlap impact and offset impact. Adopting Q3 dummy and two kinds of child restraint system(5-point harness type,impact-shield type CRS) FE model, based on the acceleration and angel from the crash conditions about frontal impact in 25%?40% and full overlap, established the numerical analysis sled crash models. Theresults show that in offset impact conditions, the X axiial displacement of children is above 523 mm, In offset impact conditions, the X axiial displacement of children is above 523 mm, the X axial displacement of children in the frontal 100% overlap rigid barrier impact condition are 513 mm and 478 mm.The displacement of Y and Z in offset impact conditions were higher than that of 100% overlap rigid barrier impact condition; under the protection of 5-point-harness CRS, the influence of the offset impact on the child occupant injury is greater than that of front 100% overlap rigid barrier impact,under the protection of front impact sheild CRS, the result is vice versa.Research shows that, in order to deal with the complex traffic accidents, the design of CRS should consider the influence of offset impact, and also provide a reference for the development of CRS regulation and the research of CRS in the future.