摘要
在大客车前碰撞中,由于前围产生较大侵入变形,极易造成驾驶员下肢损伤。为减少驾驶员下肢损伤风险,设计了一种驾驶员膝部安全气囊,并采用计算机仿真方法对气囊进行了优化分析研究。首先,利用Hypermesh建立12 m大客车的有限元模型,并对其进行正面碰撞模拟,验证了客车模型的可行性,且得到驾驶员座椅下方加速度曲线。然后,用MADYMO动力学软件建立了该大客车驾驶员约束系统的前碰撞模型,模型包含客车驾驶舱、驾驶员座椅、三点式安全带、转向系统、和膝部安全气囊。进而将有限元客车整车正面碰撞模拟获得的加速度曲线作为MADYMO碰撞模型的输入载荷条件,分析了安全带和膝部气囊的八个设计参数对驾驶员下肢损伤的影响。最后得到膝部气囊点火时刻、膝部气囊拉带长度、膝部气囊排气孔面积系数三个主效应影响因子,并基于多目标遗传算法对其进行优化分析,优化结果使驾驶员下肢损伤风险得到了很大程度的降低。
In front impact of coach,lower extremities of driver are often injured because of the large intrusion deformation of front wall. To reduce the injury risk of driver' s lower extremities,a type of driver knee airbag was designed and optimized with computer simulations. A finite element model of a 12 meter long coach was developed with Ls-dyna software. The simulation of the front impact of the coach model was carried out and the feasibility of the coach model was analyzed. Furthermore,the acceleration of the coach was acquired at the bottom of driver seat,then the front impact model for driver restraint system was established via MADYMO dynamic code. This model includes coach driver compartment,driver seat,three-point safety belt,steering system and knee airbag. The simulated acceleration curve of coach front impact was used as the input load condition in MADYMO model of the coach driver restraint system. The influence of eight design parameters of belt and knee airbag on the injuries of driver's lower extremities was analyzed. The results show that there are three key influence factors,including initiation moment of knee airbag,the strap length of knee airbag and the area coefficient for the exhaust openings of knee airbag. Based on multi-objective genetic algorithms,the optimization for the knee airbag was conducted according to these three factors. The injury risk of driver's lower extremities is greatly reduced after optimization.
出处
《机械科学与技术》
CSCD
北大核心
2015年第11期1738-1743,共6页
Mechanical Science and Technology for Aerospace Engineering
基金
国家自然科学基金项目(51275164)
湖南大学汽车车身先进设计制造国家重点实验室自主研究课题(61075004)资助
关键词
膝部气囊
下肢损伤
优化
acceleration,automobile drivers,automobile steering equipment,computer simulation,computer software,design,genetic algorithms,mathematical models,multiobjective optimization,optimization,Pareto principle,regression analysis
injury of lower extremities,knee airbag
