【作者】 马志雄；

【导师】 朱西产；

【作者基本信息】 武汉理工大学 ， 车辆工程， 2008， 博士

【摘要】 本文对车辆台车试验方法和侧面约束系统的数学仿真技术开展了研究。本文:(1)基于对实车正碰车体减速度波形的研究,发现在较低频率等级滤波的情况下正碰车体减速度波形具有双台阶特征。在此基础上提出了将正碰车体减速度波形简化成等效双梯形波形进行正碰台车试验的双加速度平台正碰台车试验方法。仿真验证表明,在台车试验中用等效双梯形波代替相应的实车正碰车体减速度波形是完全可行的。针对这一正碰台车试验方法还设计出了一种利用金属棒材作为吸能件的减速型正碰台车试验装置。(2)基于对实车侧面碰撞车门内饰板速度波形的研究,找出了车门内饰板速度波形所具有的特征。在此基础上提出了一种将车门内饰板速度波形简化为双速度平台波形进行侧碰台车试验的双速度平台侧碰台车试验方法。仿真验证表明,利用简化后的双速度平台波形代替实车侧碰内饰板速度波形进行侧碰撞台车试验是完全可行的。(3)针对目前国内还没有关于侧气囊建模技术的完整论述的现状,以安装在X车型上的头胸组合侧气囊以及安装在Y车型上的帘式侧气囊和简单侧气囊为研究对象,详述了这三种典型的侧气囊的建模过程、建模过程中需要关注的地方、在建模过程中可能会出现的问题以及解决方法。(4)针对目前国内还没有关于侧碰撞台车试验数学仿真技术完整论述的现状,详述了基于车门不变形的和基于PSM的侧碰撞台车试验的数学仿真建模方法,并对这两种侧碰台车模型的优缺点以及使用范围进行了比较。(5)通过一车门扶手与侧碰假人腹部完全对应的侧碰台车仿真模型研究了座椅、车门内饰板、侧气囊以及车门内饰板速度波形对CNCAP中侧碰假人伤害值响应指标的影响。研究表明,座椅摩擦系数和刚度仅对假人背板力有较大影响;车门内饰板材料和形面对假人的各伤害评价指标有很大影响;车辆在增加了侧气囊后假人肋骨变形量以及VC指数均得到明显改善,但假人的某些指标如耻骨力可能会增大;假人与车门内饰板的接触时间、双速度平台上两平台间的过渡段斜率以及第二个速度平台对假人伤害评价指标特别是肋骨变形量以及VC指数有很大的影响。鉴于T12力矩M_x时间历程的特殊性,分析了接触时间差对M_x大小的影响。研究表明,车门扶手与假人腹部的接触时间和骨盆接触区域与骨盆接触时间两者之间的接触时间差越短,负向M_x值越小,正向M_x越大。本文的研究成果对提高车辆约束系统的开发效率、降低开发成本,以及提高车辆侧碰安全性、改善车辆在CNCAP侧碰试验中的评价效果有十分重要的意义。更多还原

【Abstract】 Vehicle sled test method and the mathematical simulation technique of side restraint system are discussed in this doctoral dissertation. The following contents are included:(1) Based on research of the body deceleration pulse in full-scale vehicle frontal impact, the fact that the pulse has dual-level characteristic in lower frequency class filter is discovered. Simplify the deceleration of vehicle body of sled test in frontal impact into the equivalent dual-trapezia pulse. The frontal sled test method based on dual-acceleration level using the equivalent pulse will be proposed. The results of simulation validation have show that it is absolutely feasible to replace the deceleration pulse of the corresponding full-scale vehicle body in frontal impact with equivalent dual-trapezia pulse in sled test. A sled test device based on deceleration using metal sticks as absorbing energy parts has been designed about the method.(2) Based on research of the velocity pulse of door trim in full-scale vehicle side impact, get the characteristic of the velocity pulse of door trim. Simplify the velocity pulse of door trim into the dual-velocity pulse. The side sled test method using the pulse will be proposed. The results of simulation validation have show that it is absolutely feasible to replace the velocity pulse of door trim in full-scale vehicle side impact with simplified dual-velocity pulse in side sled test.(3) Whole discussion about the side airbag modeling technique has not existed so far in China. Side inflatable curtain and simple side airbag that are equipped on Y vehicle and side head-thorax airbag equipped on X vehicle are studied. Describe in detail about modeling process, attention points, problems and resolvents in the process.(4) Whole discussion about the side impact sled test mathematical simulation technique has not existed so far in China. Two mathematical simulation modeling methods of side impact sled test respectively based on the un-deformable door and PSM are discussed, and compare advantages and disadvantages as well as the usage field of two side impact sled model are compared.(5) The influence on the injury values of side dummy in CNCAP because of seat, door trim panel, side airbag and the velocity of door trim panel is studied, using a side impact sled simulation model with door armrest completely corresponding to side impact dummy abdomen. Research shows the friction coefficient of seat and the velocity of door trim panel have much effect on dummy backplate force; the material and shape of door trim influence on all dummy injury estimation index; both dummy rib deformation and VC will be improved obviously after adding side airbag, but some dummy injury index such as pubic force may increase probably; Contact time between dummy and door inner trim, the slope in transition period of two levels on dual-velocity level and the second level affect all dummy injury index especially rib deformation and VC index very much. Considering the time history particularity of T12 moment Mx, contact time difference’s influence on the magnitude of Mx is analyzed. Research has show, the shorter two contact time difference of contact time between door rest and dummy abdomen and one between pelvis contact area and pelvis is, the smaller negative Mx is but the greater positive Mx is.Research results in this doctoral dissertation will play an important role in following aspect: improving the development efficiency of vehicle restraint system, lowering development cost, enhancing vehicle side safety and improving vehicle assessment capability in CNCAP side impact test.更多还原