| Beetle elytra has the characteristics of lightweight, high strength and damage resistance. In thisdissertation, through observation of beetle elytra’ s internal structure, energy absorption andcrashworthiness of some local structures are researched by explicit finite element method. three kindsof bio-inspired lightweight and energy absorbing structures are designed base on structure character ofbeetle elytra finally: the structure of double layer cylindrical tubes, the structure of double layerconical tubes and he combination structure of six side cone tube and con tubes.The response surface functions of total energy absorption, specific Energy absorption and peekload are fitted by explicit finite element method and D-optimization experiment design method. anmulti-objective optimization of Structure geometry size was performed, which took the maximumabsorption energy, the maximum specific energy absorption and minimum initial force peak asmulti-objective Optimization index. Through the analysis and comparison of optimization results ofthree kinds of structures, the combination structure of six side cone tube and con tube has the bestenergy absorption characteristics, which can be used as ideal absorption device of car bumper.Further more, the combination structure of six side cone tube and con tube is used in car bumpersystem as energy-absorbing device, which replace the current simple stents of bumper. The analysesand comparison of bumper system with energy-absorbing device and traditional bumper system areperformed by the response surface method and ANSYS/LS-DYNA in low speed, medium speed andhigh speed conditions, which took the maximum absorption energy, the maximum specific energyabsorption and minimum initial force peak as multi-objective functions. The analysis results showedthat the abilities of buffer and absorption have improved obviously, especially the collision force peakload is decreased, which reduce personnel damage in the collision. |
PDF Full Text Request