重型汽车保险杠低速碰撞性能分析

针对某重型载重汽车保险杠开展低速碰撞安全性研究.利用Hypermesh建立有限元模型,再用LS-DYNA显式动力分析有限元软件求解分析.分别建立重型汽车保险杠系统与刚性墙低速正碰,与摆锤偏碰2种工况,得到保险杠的变形、加速度等参数,分析了某重型汽车保险杠的低速碰撞性能.根据碰撞能量相等原理进行了保险杠与刚性墙正面碰撞的台车试验,验证了仿真模型的正确性并分析产生误差的原因.试验和仿真结果表明,该型汽车保险杠在低速碰撞时变形较小,对前围部件起到了较好的保护效果.     

汽车保险杠高低温摆锤仿真和试验研究

随着汽车工业的发展和工程塑料在汽车工业中的大量应用，汽车保险杠需要兼具行人保护、造型以及轻量化等优点，所以汽车保险杠大多数是由塑料制成的，称为塑料保险杠。塑料保险杠在事故中极易受损，在前期开发阶段如果能够针对低速碰撞工况对保险杠结构进行优化设计，降低损伤风险或者减少损伤范围，则可以大大降低发生低速事故的维修费用，提升用户满意度。文章利用PAM-CRASH系统对保险杠在低速碰撞工况下进行有限元建模和碰撞模拟，设计高低温摆锤工况模拟低速碰撞工况，并在台车试验中验证仿真结果，为前期汽车保险杠结构的开发设计提供前瞻性的优化建议，降低维修成本，提升客户价值。     

你的保险杠够硬吗？：IIHS新车保险杠撞击测试

汽车保险杠是我们熟悉得不能再熟悉的部件了，它的作用是在碰撞时帮助吸收和缓冲来自外界的冲击力。降低对车辆和行人的伤害程度，同时在低速碰撞中尽量保护车头和车尾不受到损伤。然而，IIHS今年新的针对汽车保险杠的测试却显示，原来我们的保险杠并不像我们想像中的那么保险![编者按]     

汽车的低速碰撞

汽车在城市中经常发生在低速状态下正面和后面碰撞或在车辆变道时正面和后面角碰撞情况。低速碰撞可用来评估前、后保险杠的作用,但对大多数汽车制造商而言,前、后保险杠设计未放在重要位置。美国和欧洲都制定了车辆前、后端(保险杠)碰撞保护标准。在美、欧进行低速碰撞时,部分汽车制造商的保险杠设计存在不少问题,都进行了改进,如韩国现代公司Elantra、日本马自达Protege。在低速碰撞(碰撞速度8km/h)时,德国大众新甲壳虫在VRC进行保险杠四次试验中,两次无损伤,另两次仅有小损伤。有的汽车制造商在进     

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。     

保险杠的发展及应用

吸能保险杠系统在汽车低速碰撞中起着至关重要的作用。文中列举了现今汽车吸能保险杠的类型,分别说明了各类型保险杠的结构、工作原理、对汽车和行人的保护作用及在汽车上的应用状况,探讨了未来保险杠的发展方向。     

FFS法应用于汽车保险杠碰撞仿真分析研究

针对采用一般CAE分析技术判别汽车保险杠碰撞吸收能量性能精度较低的问题,首先通过某轿车前保险杠结构低速碰撞法规试验对其仿真模型进行了验证,之后采用快速精细仿真分析方法对上述试验进行了仿真模拟.试验结果和仿真结果对比表明,快速精细仿真分析方法可有效地提高汽车保险杠碰撞CAE仿真分析的精度.     

汽车保险杠正面低速碰撞仿真研究

汽车低速正面碰撞过程中，保险杠的作用不容忽视。本文依据国家强制性法规，利用ansvs／dvna软件对某保险杠系统进行计算机仿真。通过对仿真结果的分析，提出改进措施；改进后的结构仿真结果表明，保险杠的碰撞性能得到改善。     

上海别克轿车辅助气囊约束系统及故障诊断

1辅助气囊约束系统的组成 别克轿车将辅助气囊约束系统(SIR)作为标准配置,汽车识别码(VIN)的第七个位置是数字2.在气体发生器组件上有"SIR(辅助气囊约束)"字样.辅助气囊约束(SIR)系统用于在正面碰撞时保护驾驶员和乘客.     

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     

某轿车保险杠横梁结构抗撞性优化

针对某轿车在进行车速为56 km/h的正面40％偏置碰撞试验中,前保险杠横梁断裂、乘员舱侵入过大问题,主要从抗弯性能和材料等方面对前保险杠横梁提出改进方案,并利用有限元仿真方法对保险杠横梁改进方案进行仿真计算.试制改进方案样件进行了车速为56 km/h的正面40％偏置碰撞试验,试验结果表明,改进方案解决了原保险杠横梁断...     

正碰和偏置试验中的Q3损伤对比研究

针对目前儿童乘员保护不足的问题,本文在某款C级轿车上采用50km/h的正面100%重叠刚性壁障碰撞试验(简称正碰试验)和64km/h的正面40%重叠可变形壁障偏置碰撞试验(简称偏置试验)对比分析Q3儿童的损伤情况。依据C-NCAP 2021版评价规程对2个试验工况中Q3儿童进行评价。2种工况,儿童假人体现的损伤情况均严重。正碰试验中头部、颈部和胸部压缩量的损伤值更大。对胸部累积3ms合成加速度而言,偏置试验得分很低,损伤更大。目前,5点式儿童安全带起不到很好的缓冲吸能的保护效果。车辆开发商可以设计能更好保护儿童乘员的约束系统。     

基于交通事故深度调查数据的行人头部损伤特征研究

基于未来出行交通事故场景研究 （Future Mobile Traffic Accident Scenario Study,FASS） 数据库中135例人车碰 撞事故深度调查数据,对造成行人头部损伤的来源及车速对头部损伤来源的影响进行了统计分析。采用Spearman相关系 数检验法,建立了车辆速度区间与头部平均 MAIS 的回归模型。结果表明,行人头部致伤物主要来源于车辆,占比约 58%,其次为地面,占比约40%。行人事故中,碰撞车速对行人头部损伤来源的分布情况有一定的影响,当车速低于30 km/h时,行人头部损伤主要来源为地面,当车速为 ［30,50］ km/h时,车辆和地面对行人头部造成的损伤风险相近,当 车速高于 50 km/h时,行人头部损伤主要致伤物来源为车辆。因此,在进行交通损伤流行病学研究、交通损伤事故数据 库构建时,特别是在中低速碰撞中,应重视地面对头部造成损伤的风险。     

低速碰撞过程中前保结构的改进设计研究

为降低保险费用,要求车辆的主要结构在低速碰撞过程中不会产生永久性破坏。因此,文章基于RCAR试验标准,建立了某车型的低速正面碰撞有限元模型,并通过与试验结果的比较证实模型的有效性。在此模型的基础上,针对该车型在低速碰撞过程中出现的问题,对其前保险杠的吸能盒进行了改进设计,通过系统试验与整车试验,验证了设计结构的有效性,为相关设计提供重要的指导意义。     

Bumper optimum design using the dynamically equivalent beam under various impact conditions

Nowadays it is required for the bumper system to meet the various impact conditions simultaneously; barrier impact, IIHS (Insurance Institute for Highway Safety) bumper impact and pedestrian impact. Firstly, dynamically equivalent bumper beam models were developed for each impact condition and its accuracy was verified by nonlinear finite element analysis result. Dynamically equivalent pedestrian impact beam model was developed by using the equivalent forces of bumper beam and stiffeners. Pedestrian bending angle was obtained by using this equivalent pedestrian beam model. By combining these equivalent beam models, bumper optimum design program was developed. In this optimum design program, direct search method was used for the optimization algorithm. To verify the accuracy of this optimum design program, a nonlinear finite element result was used. By using this optimum design program, it can be secured the bumper impact performances in an early design stage and it will be also contributed to reduce the design time and test costs.     

Evaluating the effectiveness of a smartphone speed limit advisory application: An on-road study in Port-Harcourt,Nigeria

The development of mobile phone applications that provide speed limit advice and warnings offers opportunities for use of the technology in the improvement of driver safety. This paper looks at the effect of an advisory Intelligent Speed Assistance (ISA) application on driver speeding behaviour. Twenty participants (all males within the age range of 35–60 years) completed a within-group experimental design. Participants drove in real traffic on a 46 km test route which incorporated three-speed limits zones (50 km/h, 60 km/h, and 80 km/h speed limits) and aggregated into 10 different segments. Compared with baseline levels, possible impacts of ISA system functionalities on driver behaviour were studied through appropriate metrics including cumulative speed distribution, mean speed, speed deviation, 85th percentile speed, percentage distanced travelled above the speed limit, and safety benefit estimation. Results indicated the use of the ISA application led to significant improvement in speed limit compliance particularly in the 60 km/h and 80 km/h zones where speeding was eliminated. There were no observed negative effects on driver speeding behaviour from the use of the system. In general, the findings suggest the use of the ISA system, resulted in the adoption of vehicle speeds that are likely to improve road safety.     

正面碰撞设计中约束系统优化工况选择

2012版C-NCAP碰撞工况中的40％偏置碰撞的试验速度由56km／h提升至64km／h,而100％刚性壁正碰仍保持50km／h．两者之间巨大的速度差,使约束系统的匹配变得更加困难。文章通过分析2款轿车和1款运动型乘用车的碰撞工况,采用仿真和台车试验的手段对乘员约束系统进行优化设计,使车辆碰撞安全性能得到优化。指出按乘员伤害值、约束系统能耗密度及能耗功率大小选定最坏碰撞模式,依此设定约束系统参数,在另一碰撞模式中加以验证的约束系统设计方法。     

Profile-speed data-based models to estimate operating speeds for urban residential streets with a 30 km/h speed limit

A speed limit of 30 kilometres per hour (km/h) has been widely introduced for urban residential streets to ensure traffic safety and allow these streets to fulfil other intended functions. However, excessive speeds on these roads are very common, causing traffic safety problems and threatening the liveability of neighbourhoods. An effective and active way to deal with speeding is the application of a performance-based design approach, as mentioned in previous research. In a performance-based design approach, street geometrics and roadside elements are selected based on their influence on the desired driving speeds. The relationship between driving speeds and street features therefore needs to be determined. Although several studies have developed operating speed models for urban streets, all of these models were calibrated based on data for streets with speed limits of more than 30 km/h. The present research is designed to investigate the influence of various roadway and roadside characteristics on operating speeds on urban tangent street sections with a 30 km/h speed limit using profile-speed data. A simultaneous equation regression with a three-stage-least-square (3SLS) estimator was used for the modelling effort. The driving speed models developed in this study incorporate several street design factors, which provide helpful information for urban planners and street designers to cope with speeding issues on residential streets.     

基于瞬态响应的某轻型卡车保险杠设计

保险杠是一种具有吸收、缓和外界冲击力,保护轻型卡车前部重要的安全装置。同时保险杠有很强的造型美观功能,是轻型卡车重要的外饰件之一。文章利用有限元计算和分析的方法对某轻型卡车保险杠内板进行瞬态响应分析,并进行结构优化。经过试验台架和道路试验满足设计要求,该方法对今后轻型卡车的保险杠设计有一定的指导作用。     

Optimum SUV bumper system design considering pedestrian performance

Until recently, passenger cars have primarily interested in pedestrian protection performance. Nowadays, however, it is important for a sport-utility vehicle (SUV) to meet the bumper system standards for pedestrian safety. For a SUV bumper system, there are some difficulties in attaining a high level of pedestrian performance for the lower legform. An SUV has a high bumper position from the ground level, and the bumper approach angle must also be secured, which has an effect on car insurance fees. Due to these reasons, it is difficult to meet the pedestrian performance of the lower legform for an SUV. In this paper, a comparative study was performed on various SUV bumper systems, and a concept model for a SUV bumper system was developed, which is expected to meet the pedestrian performance by using the Pugh method. The design control factors were defined to affect the bumper pedestrian performance through the experiences of tests and analyses. For the noise factor to affect the pedestrian performance, the deviation of the impactor position was selected at the moment of impact. The design control factors were optimized by using the Taguchi optimization technique. For the Taguchi method, an L18 orthogonal array table of design control factors was used in the optimization process. Particularly, for the optimization of the bumper corner region, an optimization analysis was performed three times to meet pedestrian performance. Based on the results of the Taguchi optimization method, the sensitivity of the bumper design parameters was studied, and a new SUV bumper system is proposed that satisfies the pedestrian performance of the lower legform. The optimized bumper system should obtain a full Euro-NCAP score of 6 points for the bumper test. The pedestrian performance of the optimized bumper system is validated by using a CAE (Computer Aided Engineering) analysis, which has been proven to be in accurate. A comparison between the test and analysis results is shown for the validation of accuracy. By using the optimized bumper system, the tests and development costs of a bumper can be reduced.