可转换式儿童安全座椅前碰撞仿真研究
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摘要
儿童道路交通伤害是一个全球性的重要问题。国外在儿童乘员安全保护方面的研究起步较早,目前汽车儿童约束系统法规在世界各国已经建立并不断完善。而在中国,目前还没有相关的交通法规来对儿童乘车安全进行约束。因此,对儿童乘员约束系统的研究具有特殊重要意义。为了提高我国儿童乘员乘车的安全性,对于碰撞中儿童乘员的响应以及儿童约束系统的设计和改进的研究是非常必要的。
随着计算机的发展以及仿真理论的成熟,计算机仿真方法已经从一种汽车安全性分析的手段融入到整个汽车的研发过程中。本论文建立了汽车前碰撞3岁儿童约束系统的仿真模型。通过与该儿童座椅的台车试验结果对比,验证了该仿真模型的有效性。利用已经验证的模型,首先分别通过儿童座椅的不同设计参数、儿童座椅肩带孔位置的选择、假人在儿童座椅上的位置以及儿童座椅安全带有无松弛研究了P3假人前碰撞过程中的损伤情况;然后对P3/4假人分别使用前向式儿童安全座椅和后向式儿童安全座椅时的运动学和动力学响应进行了对比研究。仿真输出的损伤参数有头部合成加速度(aH)、胸部合成加速度(aT)、颈部轴向力(Fz)和颈部弯曲力矩(My),分析的损伤参数还包括HIC15值。
研究结果表明,增大儿童假人和儿童座椅之间的摩擦系数、提高儿童座椅和汽车座椅的坐垫刚度、降低儿童安全带的刚度能够降低儿童乘员受伤害的风险;根据不同儿童乘员的身材,选择略高于儿童肩膀高度的肩带孔位置、儿童乘员处于仰卧位置、正确佩戴儿童安全带,避免安全带松弛都有利于降低儿童乘员受伤害的程度;对于年龄比较小的儿童使用后向式儿童安全座椅能够加强对头部和颈部的保护。
最后对全文所做工作取得的成绩和不足进行了总结。本文的研究结果对于改进儿童座椅的设计参数具有参考价值,对国内儿童乘员乘车安全保护研究具有借鉴意义。
Child road traffic injury is an important problem all of the world. In foreign countries,the reaserch on safety protection for child occupants is earlier than China.Today, a lot of countries have built the regulations on child restraint system.But in China,there is still no traffic rule for the restraint of child occupants.So it is very important for the research on child restraint system.In order to improve the safety of child occupants,it is necessary to the research on response of child occupants ,design and the improvement of child restraint system in frontal impact.
With the development of the computer hardware and simulation methods, computer simulations have moved from important analysis techniques, which is one of the indispensable ways to analyze the vehicle crash safety to become integral parts of the product development process.A simulation model of frontal impact with child restraint system is built. By comparing the simulation results and the sled test results of corresponding childseat,the effectiveness of the model is validated. Based on the validated model, the influence of some childseat design parameters,the choice of the childseat shoulderbelt position, the position of the dummy in the childseat,the childseat belt has slack or not, these complications have been studied to analysis P3 dummy injuries in frontal impact firstly, then the contrast analysis of kinematics and dynamics responses for P3/4 is studied when in frontal and rear child seat.The injury parameters for output are the head acceleration(aH) ,thorax acceleration(aT),neck axial force(Fz) and neck moment(My).the injury parameter for analysis also include HIC15.
The simulation results show that,increase the friction coefficient between childseat and child dummy,enhance the stiffness of childseat cushion and carseat cushion,debase the stiffness of childseat belt may reduce the child occupants injury risk.Based on stature of different child occupants, choose the shoulderbelt hole that is a little higher than children’shoulder,children seat flat,adorn the childseat belt correctly and avoid belt slack may reduce the injury degree.For the young children ,rear-forward childseat may improve the protection effect for head and neck.
At the end of the thesis,achievement and shortage of the research are put forward.The conclusion of this paper may provide the reference value for further improvements of childseat design parameters and contribute to the research on protection of child occupants in passenger car impacts in China.
随着计算机的发展以及仿真理论的成熟,计算机仿真方法已经从一种汽车安全性分析的手段融入到整个汽车的研发过程中。本论文建立了汽车前碰撞3岁儿童约束系统的仿真模型。通过与该儿童座椅的台车试验结果对比,验证了该仿真模型的有效性。利用已经验证的模型,首先分别通过儿童座椅的不同设计参数、儿童座椅肩带孔位置的选择、假人在儿童座椅上的位置以及儿童座椅安全带有无松弛研究了P3假人前碰撞过程中的损伤情况;然后对P3/4假人分别使用前向式儿童安全座椅和后向式儿童安全座椅时的运动学和动力学响应进行了对比研究。仿真输出的损伤参数有头部合成加速度(aH)、胸部合成加速度(aT)、颈部轴向力(Fz)和颈部弯曲力矩(My),分析的损伤参数还包括HIC15值。
研究结果表明,增大儿童假人和儿童座椅之间的摩擦系数、提高儿童座椅和汽车座椅的坐垫刚度、降低儿童安全带的刚度能够降低儿童乘员受伤害的风险;根据不同儿童乘员的身材,选择略高于儿童肩膀高度的肩带孔位置、儿童乘员处于仰卧位置、正确佩戴儿童安全带,避免安全带松弛都有利于降低儿童乘员受伤害的程度;对于年龄比较小的儿童使用后向式儿童安全座椅能够加强对头部和颈部的保护。
最后对全文所做工作取得的成绩和不足进行了总结。本文的研究结果对于改进儿童座椅的设计参数具有参考价值,对国内儿童乘员乘车安全保护研究具有借鉴意义。
Child road traffic injury is an important problem all of the world. In foreign countries,the reaserch on safety protection for child occupants is earlier than China.Today, a lot of countries have built the regulations on child restraint system.But in China,there is still no traffic rule for the restraint of child occupants.So it is very important for the research on child restraint system.In order to improve the safety of child occupants,it is necessary to the research on response of child occupants ,design and the improvement of child restraint system in frontal impact.
With the development of the computer hardware and simulation methods, computer simulations have moved from important analysis techniques, which is one of the indispensable ways to analyze the vehicle crash safety to become integral parts of the product development process.A simulation model of frontal impact with child restraint system is built. By comparing the simulation results and the sled test results of corresponding childseat,the effectiveness of the model is validated. Based on the validated model, the influence of some childseat design parameters,the choice of the childseat shoulderbelt position, the position of the dummy in the childseat,the childseat belt has slack or not, these complications have been studied to analysis P3 dummy injuries in frontal impact firstly, then the contrast analysis of kinematics and dynamics responses for P3/4 is studied when in frontal and rear child seat.The injury parameters for output are the head acceleration(aH) ,thorax acceleration(aT),neck axial force(Fz) and neck moment(My).the injury parameter for analysis also include HIC15.
The simulation results show that,increase the friction coefficient between childseat and child dummy,enhance the stiffness of childseat cushion and carseat cushion,debase the stiffness of childseat belt may reduce the child occupants injury risk.Based on stature of different child occupants, choose the shoulderbelt hole that is a little higher than children’shoulder,children seat flat,adorn the childseat belt correctly and avoid belt slack may reduce the injury degree.For the young children ,rear-forward childseat may improve the protection effect for head and neck.
At the end of the thesis,achievement and shortage of the research are put forward.The conclusion of this paper may provide the reference value for further improvements of childseat design parameters and contribute to the research on protection of child occupants in passenger car impacts in China.
引文
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[2] Klaus LH, Thomas, Muller CB.Experience with airbag-equipped cars in real-life accidents in Germany. 1996. Melbourne, Australia. National Highway Traffic Safety Administration, Washington.DC.USA
[3] J-Y. Foret-Bruno, X. Trosseille, J-y. Le Coz. Thoracic Injury Risk in Frontal Car Crashes with Occupant Restrained with Belt Load Limiter. SAE Paper 983166
[4]公安部交通管理局.《中华人民共和国道路交通事故统计资料汇编》.2003
[5] NHTSA.Traffic Safety Facts 2006 Data.www.nhtsa.gov
[6]张曙曦.看图学安全:12岁以下儿童须坐汽车后座.http://auto.sohu.com. /2005215/n240986233.shtml, 2005-12-15
[7] Burdi A.R.,Huelke D.F., Snyder R.G.,et al.Infants and children in the adult world of automobile safety design:Pediatric and anatomical consid- erations for design of child restraints.Journal of Biomechanics,1969,2: 267-280
[8] Gennarelli.T..Mechanisms of brain injury.Emergency Medicine,1993,11: 5-11
[9] Gray H..Gray's Anatomy.Courage Books.Philadelphia, Pennsylvania, USA, 1901
[10] Viano C,King A.I,Melvin J.W,et al.Injury Biomechanics Research:an essential element in the Prevention of Trauma.J Biomech,1989,22(5): 403-417
[11] Brun-Cassan F., et al..Comparative Study of Restrained Child Dummies and Cadavers in Experimental Crashes.SAE 933105,1993
[12] Foust D. R.,Bowan B. M.,Snyder R. G..Study of Human Impact Tolerance Using Investigations and Simulations of Free-falls.SAE 770915,1977
[13] Snyder R. G..Impact Injury Tolerances of Infants and Children in Free-fall. In:13th Annual Proceedings Association for the Advancement of Automotive Medicine.1969
[14] Sturtz G..Biomechanical Data of Children.SAE 801313, 1980
[15] Eichelberger M.R..Pediatric Trauma:Prevention,Acute Care,Rehabilitation. Mosby-Year Book.1993
[16]胡军.孩子乘车要坐专用座椅.BEIJING INDUSTRY & COMMERCE.2003-04
[17]魏朗,刘浩学.汽车安全技术概论.北京:人民交通出版社,1999
[18] Kallieris D.,Barz J.,Schmidt G.,et al.Comparison between child cadavers and child dummy by using child restraint systems in simulated collisions.SAE 760815,1976
[19]霍庆泽.汽车儿童安全座椅的发展历史.世界汽车安全,2008-09
[20] Sherwood C.,Marshall R.,Crandall J..The Development of an Injury Cost Function for Child Passenger Safety.ESV20,Paper Number 07-0127
[21]柳柽.儿童安全座椅.汽车杂志,2004-05-105
[22]马玉春,聂磊.儿童乘车安全误区及对策.科技信息,2006-09
[23]罗萌,唐亮,杜汇良等.儿童约束系统动态仿真研究及初步参数分析.汽车技术,2006
[24]魏哲,强毅.汽车儿童约束系统技术法规和标准研究.机械工业标准化与质量,2008-12
[25] NHTSA.Child Passenger Safety.www.nhtsa.gov
[26]周宏潮.汽车是如何工作的?(二十八)儿童约束系统.轿车情报,2007-05
[27] MADYMO Theory Manual Version 6.2.1.TNO Road-vehicles Research Institute,2004
[28] MADYMO Application Manual Version6.2.1. TNO Road-vehicles Research Institute, 2004
[29] MADYMO Utilities Manual Version6.2.1.TNO Road-vehicles Research Institute,2004
[30] MADYMO Model Manual Version 6.2.1.TNO Road-vehicles Research Institute,2004
[31] MADYMO User’s Manual 2D Version6.2.1.TNO Road-vehicles Research Institute,2004
[32] MADYMO User’s Manual 3D Version6.2.1.TNO Road-vehicles Research Institute,2004
[33] Kathleen DeSantis Klinich TRC,Roger A. Saul,NRD-20,et al.Techniques for developing child dummy protection reference values.Event report.1996,1-3
[34]石城.儿童安全座椅国内外发展现状.www.pcauto.com.cn/safe/buy/body/061 2/415911.html
[35] Kathleen Weber. Crash Protection for Child Passengers [J].UMTRI Research Review, 2000,31:3-12
[36] Economic Commission of Europe Regulation 44, Revision 2-Amendment 4 [S]. February 2008
[37] National Highway Traffic Safety Administration.FMVSS213:Child Restraint Systems. 2003
[38] K Weber. Rear-Facing restraint for small child passengers.UMTRI Research Review, Volume 25, 1995
[39]刘延柱.多刚体系统动力学.北京:高等教育出版社,1989.3
[40] Gray H.Gray's Anatomy.Courage Books. Philadelphia, Pennsylvania,USA,1901
[41] Menon.R.,Ghati Y.,Jain P..Madymo Simulation Study to Optimize the seating angles and belt positioning of high back booster seats. ESV20,Paper Number 07-0091
[42] Singh S.,McCray L..The effect of restraint use and crash mode on injury severity risk for children. ESV20,Paper Number 07-0216
[43]黄世霖.汽车碰撞与安全.北京:清华大学出版社,2000
[44] The Abbreviated Injury Scale-1990 revision:Association for the Advancement of Automotive Medicine, 2340 Des Plaines River Road, Suite 106,Des Plained, II 60018,USA, 1990
[45] Parenteau C.,Viano D. C.. Field data analysis of rear occupant injuries,Part II: Children, toddlers and infants.SAE 2003-01-0154,2003
[46] K Langwieder,W Hell,H Willson. Performance of child restraint systems in real-life lateral collisions.SAE,05-0330-0
[47]袁健,任山.汽车安全儿童约束系统的发展研究.天津:中国汽车技术研究中心,2005
[48] Gotschall C S,Sluchter. Head injuries to motor vehicle occupants’aged 0-5 years.Children’s National Medical Center. Washington DC, USA, September 1999
[49]杨杏梅.汽车前碰撞中6岁儿童乘员约束系统的仿真研究:[湖南大学硕士学位论文].长沙:湖南大学,2006
[50] Elisa R. Braver,Randy Whitfield,Susan A.Ferguson.Risk of death among child passengers in front and rear seating positions.SAE 973298,1997
[51]葛如海,苗强.车用儿童约束装置综述.中国安全科学学报,2006,16 (4): 42-47
[52] N Yoganandan,S Kumaresan, F A Pintar,TA Gennareui. Biomechanical tolerance criteria for pediatric populatons. Department of Neurosurgery, Medical College of Wisconsin, USA, 1999
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