| With the advancement of modernization process and improvement of economicdevelopmental rate in China, people’s living standards have greatly enhanced and carownership is growing. However, the number of traffic accidents is increasing at thesame time. Among the accidents, rear-end impact accounts for a great part, resulting inthe growth of neck injury which brings a lot of loss to property and threatens personalsafety. Therefore, it is of great significance to study the condition of neck injury inrear-end impact through the construction of the sled test system to stimulate real vehiclecollisions.After comprehensively surveying the current development status of domestic andabroad sled test system, and analyzing the characteristics of neck injury in rear-endimpact, the thesis designed an overall solution from a sled buffer energy absorbingdevice to the neck injury detection. By the application of finite element, the thesisstimulated sled test system which meets the requirement of rear-end impact test.According to the stimulation result, each part of the system was designed and built onwhich the rear-end impact test was proceeded on fake human and animal respectively,and the neck injury condition was evaluated and analyzed to examine the function of thewhole system. Meanwhile, a further study was made on the results of stimulation andtest. The main research work is as follows:①A deep and systematical investigation was done according to kinetic analysisand the procedure of neck injury. Various types of crash tests were comprehensivelyanalyzed. Especially, the related rear-end impact studies; injury procedure andevaluation criteria were focused.②A computer-based simulation of rear-end impact sled test system wasconducted by finite element analysis software ANSYS/LS-DYNA. By contact-impactanalysis, simulation of deceleration curve meeting the requirement of the rear-endimpact regulations was achieved. The result of stimulation was consistent with that ofreal vehicle crash test. On this basis, the effect of impact velocity and quality of sled aswell as the number of energy absorbing tubes on the sled deceleration curve was furtheranalyzed, laying the foundation for the construction of following rear-end impact sledsystem and related tests.③According to the stimulation result and available test condition, test field, extraction device, data acquisition systems, high-speed camera systems and opticalvelocimetry system were built. Sled, seats system and energy absorbing buffer systemwere designed. Finally, the rear-end impact sled was founded, preparing for thefollowing test.④On the constructed system of rear-end impact sled test, validation tests wereproceeded on fake human and animal respectively. Under the different collision velocity,the activity and injury condition of dummy neck were observed in dummy test. Whilethe animal test was used to investigate the neck injury site after rear-end impact. Thetwo kinds of validation test verify that rear-end impact sled test can stimulate the realsituation of rear-end impact and neck injury condition. A further analysis was made.Through the theoretical study and validation test, it is proved that the system ofrear-end impact sled test designed and built in this project is feasible. The system notonly stimulates the real rear-end impact accident but also simultaneously monitors anddetects the whole process of neck injury caused by the rear-end impact accident andreliably reflects the neck injury procedure and condition in the rear-end impact accident.Thus it provides evidence for related fields’ study, such as neck injury mechanism inaccident, vehicle safety design, medical care and diseases treatment. |
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