Research On The Difference Of Dynamic Response Between Child Anthropomorphic Test Device And Human Model In Child Restraint System

With the increasing of car quantity year by year, people put more and more attention on children’s car safety. More and more parents choose putting child occupant in child restraint system(CRS), the use of child restraint system reduced the casualty rate of child occupant in the traffic accident significantly. At present, there are so many types of child restraint system on the market, children from different ages need to choose the appropriate child restraint system according to their sizes. As a mechanical substitute, anthropomorphic test devices(ATDs; also known as dummies)which act as child occupant in crash simulation environment to evaluate the safety performance of the various child restraint systems. For traditional constraint system, fivepoint harness system and heightening cushion, anthropomorphic test device can evaluate their safety performance accurately; However, for the impact shield system, current ATD can not evaluate its real performance accurately. This paper combine test and computer simulation, conduct study on the difference of dynamic response between child anthropomorphic test device and human model in child restraint system in frontal impact and side impact respectively.This paper established simulation models in MADYMO software according ECE R129 regulation. Research on the dynamic response between Q-series child simulation dummies and child human model. Research on the difference of dynamic response between child anthropomorphic test device and human model in frontal impact and side impact in simulation environment, make comparison between kinematics response and dynamic response.Research results show that in a head-on collision, Q-series of children’s test dummies thoracic rigidity is larger than child human model, in rebound process, Q-series of children’s test dummy hip is raised backward, the torso of the dummy behaves similar to a rigid body and begins to rotate around the upper edge of the impact shield, child dummy model has thrown the trend of safety seat; For child human model, the human torso model fit front body, head makes contact with the surface of shield, and X direction displacement of head is larger than Q1.5 child test dummy. In the side impact, the posture between Q3 child test dummy model and three-year-old child human model show great difference, from the head, chest, pelvis trajectory curve can clearly see the differences. The damage parameter, the head and the pelvis injury values are similar between them, but the chest injury value varied widely. In addition, two swing arms are also different the limb joint stiffness of Q-series of child test dummy is larger, in the motion process, the limbs is more "rigid" than real human model.Finally the findings from this study lead to the assumption that the Q-dummies are not the best device to examine impact shield CRS, especially the ejection risk may not be assessable correctly. Therefore, the investigation on dummy design has to be continued with a focus on the flexibility of the thoracic and lumbar spine so that current ATD can evaluate the performances of all kinds of CRS accurately.