低速碰撞的安全气囊点火时刻分析方法的研究

整车安全性能应同时满足NCAP体系的要求和中低速碰撞的乘员保护要求。本文中从车体碰撞强度和乘员伤害的角度出发,利用MADYMO软件优化气囊点火时刻,为气囊标定提供参考;同时总结了低速碰撞的乘员伤害评价限值,使乘员在不同的碰撞工况下都能得到最佳保护。     

基于RCAR正面保险杠测试的约束系统标定原则

欧盟RCAR自2011年1月新增保险杠低速碰撞的测试程序,并将测试结果正式加入保险等级评估程序中.若碰撞过程中气囊起爆,不但会增加维修成本,而且会影响保险等级和汽车销售情况.通过分析某车型在10 km/h保险杠测试工况下30～50 ms处碰撞传感器位置的加速度、速度与点火阈值的关系,提出低速碰撞约束系统设计原则.为权衡气囊误爆与汽车可维修性的关系,应在设计初期合理安排约束系统标定和分析,将此工况纳入约束系统标定试验矩阵中.     

基于零部件试验的汽车侧面碰撞假人伤害的研究

为改善某款国产车型的侧面碰撞安全性,基于整车侧面碰撞试验和侧面气囊与车门内饰等零部件冲击试验,建立了该车侧面安全气囊和腹部与髋部侧面碰撞MADYMO子模型.运用侧面碰撞理论模型研究了假人伤害机理和车身各参数之间的相关性,通过计算机仿真,对车门内饰板相关部位的结构和侧面气囊进行了改进优化,并得到零部件试验的验证.结果表明,通过零部件试验的方法能有效降低假人伤害,提高汽车侧面碰撞安全性.     

好东西

安全气囊服 当摩托车驾驶员在遭遇车辆碰撞事故时,身体离开车辆的瞬间,气囊服保险绳会带动球销从球座装置上迅速脱离,气瓶座内的空心撞针将气瓶击穿,气瓶内的气体在0.5秒内迅速充满车服夹层内的气囊,从而有效地保护人体的颈椎、胸椎、腰椎、尾椎等重要部位,将人体的伤害降至最低。     

汽车防追尾外置安全气囊预警系统设计与仿真

高速公路发生追尾时对汽车破坏性巨大且人员伤亡率极高,为减少追尾事故带来的伤害设计了一套汽车防追尾外置安全气囊预警系统。该系统通过数学模型来对危险进行判定分析,采取安全距离预警、外置安全气囊点爆和安全带分级预紧三种措施,最大限度地卸去碰撞时的冲击力。实现碰撞前预警,碰撞前提前约束人体,点爆气囊,在发生追尾事故时为乘员提供最全面的保护。通过建立CarSim与Simulink的联合模型验证了系统的可行性。     

某车型正面碰撞乘员颈部保护性能提升

某车型在正碰开发试验过程中,驾驶员颈部伤害值不满足正面碰撞的乘员保护法规。通过分析假人颈部伤害机理、假人运动情况和安全带等约束系统部件的工作情况,得出造成颈部伤害的因素主要是安全带对假人躯干的约束效果差,正面气囊刚度偏大。通过取消安全带限力装置,调整正面气囊的刚度,最终实车试验验证颈部伤害值满足法规要求。     

上海别克轿车辅助气囊约束系统及其故障诊断

1辅助气囊约束系统的结构上海别克轿车将辅助气囊约束系统(SIR)作为标准配置。辅助气囊约束系统(SIR)用于在正面碰撞时保护驾驶员和乘客。所有气囊只有在正面碰撞或偏离汽车中心线小于30°的近似正面碰撞时才膨开。系统在反向碰撞、侧面碰撞或翻车时不膨开。即只有当产生一个足     

2007款奥迪TT乘员保护系统解析

乘员保护系统是汽车被动安全的一部分,它主要有安全气囊和安全带二者共同作用,当汽车遭受一定碰撞力后,系统会点燃引爆材料引发化学反应,隐藏在车内的安全气囊就在瞬间充气弹出,在乘员身体与车内零部件碰撞之前及时到位,在人体接触到安全气囊时,安全气囊通过气囊背面气孔排气,减轻身体所受冲击力,达到减轻乘员伤害的效果.     

维修安全气囊(SRS)须知

安全气囊是现代的被动性安全装置之一,对驾乘人员头部、颈部的安全有十分明显的保护作用,特别是在汽车发生正面及侧向碰撞时,其保护作用更明显.安全气囊的工作过程非常迅速,当汽车发生碰撞时,碰撞传感器检测出碰撞强度,并将信号传给电控单元(ECU),对于中等强度以上的碰撞,电控单元向气囊组件发出指令,在极短的时间内气囊迅速充气胀起,当人体接触到气囊时,气囊逐渐泄气,从而对驾乘人员缓冲保护,整个过程仅需几分之一秒.     

正面全宽碰撞试验中假人胸部伤害研究

通过台车试验,对受方向盘角度影响和座椅刚度等影响下的几种典型的胸部伤害情况进行了分析研究,指出了在无安全气囊或气囊作用偏弱的情况下,方向盘的水平角度一般时容易造成胸部加速度偏大,方向盘水平角度偏大时容易造成胸部压缩变形量偏大;另外,也指出了碰撞中,坐垫的深度偏大和前端刚度偏强时容易增大假人胸部伤害,坐垫前端刚度偏弱时导致假人下沉可造成胸部伤害指标提高,这为约束系统的匹配提供了参考。     

驾驶员安全气囊的仿真优化研究

在MADYMO中建立安全气囊的模型,并应用PSM子结构方法建立了车人的简要模型。通过对计算机仿真数据与实验进行对比,并在此基础上从气囊直径、排气孔直径、气流率3个方面对安全气囊进行了优化,使其在正面碰撞中对驾驶员的保护作用有了明显提高。     

女性汽车驾驶员正面碰撞伤害分析及安全性能优化

本文利用MADYMO软件对第5百分位女性驾驶员在50km/h正面碰撞中的表现进行了仿真,对转向管柱角度、安全带限力等级、安全气囊点火时刻以及安全气囊排气孔大小等因素对女性驾驶员伤害的影响进行了分析,并对女性驾驶员的正面碰撞安全性能进行了优化。     

Performance evaluation of slim low-risk-deployment dual-type passenger airbag system with dispersed inflation pressure

Motor vehicle passenger airbags have been proven to be effective for reducing the possibility of passenger injury during a crash. However, the inflation of the airbag sometimes causes serious injury when a passenger is positioned close to the airbag. The United States Federal Motor Vehicle Safety Standard (FMVSS) 208 requires the use of a low-riskdeployment (LRD) passenger airbag system. This paper proposes a newly developed airbag system comprising two slim airbags mounted on the instrument panel. A series of tests were conducted using the FMVSS 208 test procedures to demonstrate the effectiveness of the proposed system. It was found that the system not only satisfied the injury criteria of FMVSS 208, but was also effective for protecting passengers of all sizes.     

Using on-board video data for safety analysis – An analysis of right hook crashes involving large buses at signalized intersections

Bus right hook (BRH) crashes at intersections are one of the most common types of crashes for bus carriers, which accounted for as high as 16% of fatal and injury crashes involving large buses at intersections in Taiwan. A BRH crash occurs when a bus and another vehicle traveling in the same direction head into an intersection, but the bus driver makes a right turn across the path of the through-moving vehicle, and both vehicles collide. This study responds to the research needs to identity factors associated with BRH crashes by utilizing in-vehicle data recorder (IVDR) data. A four step analysis procedure was developed, including (1) video data coding, (2) crash sequence analysis to identify crash contributing factors, (3) a case-control study to examine the relationship between the crash contributing factors and crash occurrence, and (4) modeling crash risk in terms of the crash contributing factors to better understand the crash generating process. This study first identified the existence of driver unattended time as the time between when the driver last checked the right back mirror to finally steering for a right turn, indicating the time period wherein the driver did not track the through vehicle on the right side using the right back mirror. It was found that BRH crashes could be attributed to the concurrence of unattended time and the speed difference between the bus and through vehicle. Several recommendations are discussed based on the results to further develop countermeasures to reduce this type of crash.     

气袋折叠方式对离位乘员伤害的影响分析

提高安全气袋的乘员保护效能,减少其可能造成的伤害,是汽车被动安全研究的重要内容。使用LS-DYNA软件建立了5种不同折叠方式的气袋有限元模型,结合静态点爆试验结果对气袋有限元模型进行了验证。按照两类离位乘员的典型形式,进行了不同折叠方式气袋对离位乘员伤害的仿真分析,结果表明卷绕式折叠和折入式折叠气袋综合性能优于平面直接折叠气袋。研究结果可为气袋折叠方式优化设计提供指导。     

Investigating fatal and injury crash patterns of teen drivers with unsupervised learning algorithms

Teenagers have been emphasized as a critical driver population class because of their overrepresentation in fatal and injury crashes. The conventional parametric approaches rest on few predefined assumptions, which might not always be valid considering the complicated nature of teen drivers' crash characteristics that are reflected by multidimensional crash datasets. Also, individual attributes may be more speculative when combined with other factors. This research employed joint correspondence analysis (JCA) and association rule mining (ARM) to investigate the fatal and injury crash patterns of at-fault teen drivers (aged 15 to 19 years) in Louisiana. The unsupervised learning algorithms can explore meaningful associations among crash categories without restricting the nature of variables. The analyses discover intriguing associations to understand the potential causes and effects of crashes. For example, alcohol impairment results in fatal crashes with passengers, daytimes severe collisions occur to unrestrained drivers who have exceeded the posted speed limits, and adverse weather conditions are associated with moderate injury crashes. The findings also reveal how the behavior patterns connected with teen driver crashes, such as distracted driving in the morning hours, alcohol intoxication or using cellphone in pickup trucks, and so on. The research results can lead to effectively targeted teen driver education programs to mitigate risky driving maneuvers. Also, prioritizing crash attributes of key interconnections can help to develop practical safety countermeasures. Strategy that covers multiple interventions could be more effective in curtailing teenagers' crash risk.     

中重型卡车安全气囊开发研究和相关探讨

中国中重型卡车在安全气囊开发方面存在的问题中重型卡车按照驾驶室种类分为长头卡车和平头卡车,在20世纪90年代之前,中国的中重型卡车主要为长头卡车,随着时间的推移,平头卡车逐渐成为主流,目前所占比例能够达到98%。随着卡车技术的发展,为了减少卡车碰撞事故中的伤亡率,很多公司都计划在卡车上安装安全气囊,在产品和技术上与国际接轨。在汉诺威车展上,奔驰(图1)、沃尔沃(图2)、曼等品牌的卡车     

Effects of head restraint and vehicle damage severity on neck injury risk

Domestic automobile insurance claims were investigated to correlate the driver neck injury risk with the safety rating of the head restraint, the severity of vehicle damage, and other human factors. The results of our statistical analysis reveal that the risk of neck injury for the driver is significantly different for vehicle size, use, driver gender, driver age, impact direction, accident location, and safety rating of head restraint, depending on vehicle the damage level which is assumed to imply impact severity during a rear-end crash accident. One of the unique findings from domestic insurance claims from low-speed rear-end crash accidents is the frequent reports of lower back injury together with whiplash. Thus, the risk of lower back discomfort is also included in this statistical analysis.     

微型轿车安全带系统优化与验证

通过实车试验数据分析,讨论了微型轿车无气囊条件下的乘员伤害.使用Madymo分析方法对安全带参数进行了优化,提出使用限力安全带降低伤害值的方法.台车验证表明,对于刚性很强的尺寸紧凑型微型轿车,使用限力式安全带,可以有效降低正面碰撞头部加速度,使车辆正面碰撞乘员保护达到中国法规要求.     

汽车安全气囊起爆车速与乘员伤害关系的仿真研究

利用碰撞受害者模拟软件MADYMO建立了某客车乘员约束系统前碰撞计算机仿真模型,通过对不同碰撞车速下乘员伤害值的仿真计算,研究了保证乘员伤害指标达到一定要求的汽车安全气囊起爆车速。使用生物力学灰度区的概念描述和确定气体发生器的点火阈值,也就是从乘员保护的观点出发,确定不同结构汽车的气囊点火车速,从而为整车匹配安全气囊提供了良好的手段和依据,并能够大大降低匹配时间和周期。