轿车安全带及安全气囊

近年来，随着轿车市场的日益火爆、国内各大轿车厂家纷纷加入降价行列的同时，汽车的安全性也成为轿车的一大卖点，ABS、安全气囊、安全舱结构等成了轿车生产厂家和经销商推销产品的重要筹码而大力宣传。但是，在各种令人眼花缭乱的安全设计和安全装置中，安全气囊却有着一定的独特性，它不比空调、音响等车载装置，     

聚焦安全气囊事件 事故频发致汽车大规模召回

正"安全气囊"国外案件盘点首先,让我们回顾一下被媒体陆续曝光的装有高田气囊的本田汽车"杀人案",车型主要有雅阁、思域等。2009年5月16日,事件发生在美国。18岁的埃希利·帕海姆准备去接放学的弟弟,在学校的停车场,她驾驶的本田雅阁与另外一辆汽车相撞。雅阁轿车的安全气囊弹出后,不仅未起到保护驾驶者的作用,驾驶者反而被安全气囊中弹出的金属碎片划破颈动脉。花样年纪的埃希利·帕海姆最终死亡,也从此揭开了高田气囊和本田汽车伤人致死的内幕。     

轿车安全带及安全气囊

近年来,随着轿车市场的日益火爆、国内各大轿车厂家纷纷加入降价行列的同时,汽车的安全性也成为轿车的一大卖点,ABS、安全气囊、安全舱结构等成了轿车生产厂家和经销商推销产品的重要筹码而大力宣传.但是,在各种令人眼花缭乱的安全设计和安全装置中,安全气囊却有着一定的独特性,它不比空调、音响等车载装置,其作用实际上是有着很严格的条件限制的,并且只在某一范围内才产生作用.若不了解安全气囊的工作条件和范围,而一味地认为有了气囊就万事无忧了,最终安全气囊可能非但不会起到安全的作用,而且还给驾乘人员造成其他意外的伤害.     

汽车用安全气囊及其织物

目前，我国的汽车工业作为支柱产业发展很快，汽车特别是轻、小型汽车的安全行驶已经成为汽车生产厂家和广大乘员关注的热点。汽车安全气囊就是随着这个热点应运而生的新生事物。有关资料显示．汽车配备了安全气囊后，车辆正面冲撞时乘员死亡率约降低30％，前部撞车时死亡率约降低18％。另外，系好安全带的乘员在车祸中的受伤程度也有所减轻。越来越多的出厂汽车装备了安全气囊系统，安全气囊已成为汽车的标准部件。     

汽车安全气囊用药危险性实验研究

为了确定汽车安全气囊用药的危险性,根据其成分组成选取75℃热稳定性实验、时间/压力实验、克南实验、撞击敏感度实验、摩擦敏感度实验以及固体氧化性实验对汽车安全气囊用药进行测试并分析实验结果判断其危险性.实验结果表明:汽车安全气囊用药是热稳定的；时间/压力实验中发生猛烈爆燃,在商业包装正常条件下能够显示爆燃的能力；克南实验极限直径为3.0mm,在封闭条件下加热显示效应；撞击敏感度实验以及摩擦敏感度实验均未出现特殊现象,气囊用药可以以其实验的形式运输；气囊用药具有氧化性.结合相关标准及法规进行综合判断,可以确定汽车安全气囊用药的危险性并且划分危险类别,对保证汽车安全气囊用药的生产、运输、储存等过程的安全具有指导意义.     

使用安全气囊 未必高枕无忧

轿车安装安全气囊已经相当普遍。但安全气囊是否对乘员的安全有绝对的保障,专家指出,未必可以高枕无忧。安全气囊作用于车辆受撞、乘员生命受到威胁的紧急关头充气打开,以有效保护乘员。但气囊须在车辆中等至严重程度的正面碰撞或接近正面碰撞的情况下,才能充气打开。如若车辆非此种受撞,气囊     

安全气囊的作用、种类、结构及正确使用

安全气囊,也称辅助乘员保护系统,是一种当汽车遭到碰撞而急剧减速时能很快膨胀的缓冲气囊,是一种被动安全装置,它可以保护车内乘员不致撞到车厢内部。     

用于汽车安全气囊的气体发生器产气性能研究

建立了模拟汽车碰撞过程的实验系统;利用该系统模拟汽车碰撞时产生的撞击信号触发气体发生器开始工作,对模拟安全气囊的密闭、定容积的充气筒内产生的p-t曲线、气体发生器内部的p-t曲线、撞击时产生的a-t曲线进行测试并得到相关测试参数值;从而对气体发生器的产气性能进行研究。测试结果表明,温度对安全气囊的工作有一定影响。利用该测试系统测试得到的数据与美国BREED公司对同类产品的测试结果比较,有很好的相比性,测得的数据可作为气体发生器生产质量的检验依据。     

解决汽车行业的“痛中之痛”需尽快行动

正一个个血淋淋的例子,让人不得不将安全气囊的"安全"两字打上问号。汽车安全气囊的鱼目混珠,除了暴利的诱惑外,还因为中国目前缺乏关于安全气囊的相关标准和法规监管。即使是原厂气囊,也时常会出现"该爆时候未爆"的情况。由于缺乏统一的检测标准,责任难以界定,这就使得安全气囊问题成为汽车行业的"痛中之痛"。中国车主关于安全气囊的心病10年前买车,消费者可能会问:"这车有没     

儿童不应坐副驾驶

副驾驶是汽车上最危险的位置,家长不要让儿童坐在副驾驶位置。儿童在这个位置上不仅遇到事故时受损害大,而且儿童的好动性还会干扰正常驾驶诱发事故。同时,儿童坐在装有安全气囊的副驾驶位置,安全气囊     

Feasibility Study of Airbag Concept Applicable to Motorcycles Without Sufficient Reaction Structure

Objectives: An airbag system for motorcycle applications was developed and marketed in 2006 followed by many research projects on the system. In the airbag system, the bag should be supported during the kinetic energy–absorbing period of a rider in a collision. The previously developed system employed a configuration in which motorcycle structures support the airbag, such as a gauge unit and/or a steering structure. The supporting structure functions to receive the reaction force to hold the airbag during a crash to properly absorb the rider's kinetic energy. However, the previous system requires a larger area for this reaction structure and is applicable only to the motorcycles that can provide that area. To overcome this limitation, we propose an airbag system employing another concept. In this concept, the airbag does not use its vehicle structures as a reaction structure but uses the structures of an opposing vehicle, such as doors and/or pillars of an opposing vehicle. In this project, we aim to verify the effectiveness of the proposed system when installed in a motorcycle that cannot provide a larger area for the reaction structure.

Methods: In the system with this concept, it is assumed that the occupant protection performance is largely affected depending on impact configurations. Accordingly, full-scale motorcycle-to-car crash tests using 125 cm³ scooter-type models with and without the proposed system were conducted in various impact configurations. The 7 impact configurations specified in ISO 13232 were selected as the test configurations. Injury variables and injury indices of head, neck, chest, and abdomen were evaluated with the motorcyclist dummy.

Results: Injury variables and indices obtained from the crash tests with the airbag were compared to those of the baseline tests. In 2 impact configurations, the airbags were supported by the side structures of the opposing vehicle and performed to reduce the injury variable of head and/or chest compared to that of the baseline test.

Conclusion: Through the crash tests, beneficial protection effects of the airbag system were confirmed in particular impact configurations. No significant risk for the occupant due to the airbag was observed in the conducted crash tests. It was concluded that the proposed airbag system has feasibility to reduce rider injury in a collision of a motorcycle without sufficient reaction structure.     

Airbag for the closing of pipelines on explosions and leakages

This paper is a result of international effort aimed at the construction of a device for quick closing of pipelines in the case of explosion propagation and/or chemical leakage. Such a problem exists in industries where flammable substances are transported by pipelines. The basic solution principle was the idea to use airbags similar to those utilized in cars.

Two pipeline applications were taken into consideration: a low-pressure module able to suppress explosion propagation and a high-pressure module to stop leakages from, e.g. natural gas pipeline capable to be used for duct diameters up to 0.6 m, pressures up to 5 MPa and reaction times of 50 ms. It was necessary to construct a new airbag, capable of withstanding up to 10 bar pressure. The choice of material was critical to ensure sufficient strength and chemical resistance while retaining impermeability.

CFD modeling of the bag deployment into a pipe flow and analysis of the bag shapes was also completed. Two gas generators were constructed and tested with novel propellant materials.

Different airbag models were tested to evaluate their effectiveness. Risk analysis approach was applied to evaluate the safety and economic benefits of the new technology in different fields of application.     

Potential of a Precrash Lateral Occupant Movement in Side Collisions of (Electric) Minicars

Objective: In minicars, the survival space between the side structure and occupant is smaller than in conventional cars. This is an issue in side collisions. Therefore, in this article a solution is studied in which a lateral seat movement is imposed in the precrash phase. It generates a pre-acceleration and an initial velocity of the occupant, thus reducing the loads due to the side impact.

Methods: The assessment of the potential is done by numerical simulations and a full-vehicle crash test. The optimal parameters of the restraint system including the precrash movement, time-to-fire of head and side airbag, etc., are found using metamodel-based optimization methods by minimizing occupant loads according to European New Car Assessment Programme (Euro NCAP).

Results: The metamodel-based optimization approach is able to tune the restraint system parameters. The numerical simulations show a significant averaged reduction of 22.3% in occupant loads.

Conclusion: The results show that the lateral precrash occupant movement offers better occupant protection in side collisions.     

Experimental simulation of airbag deployment for pipeline closing

Small scale tests were carried out at ISL's shock tube facility STA (100 mm inner diameter) to study the problem of closing a pipeline by means of an airbag in case of explosions or gas leakages. Experiments were carried out to simulate the flow in a pipeline at velocities and gas pressures as present in pipeline flows. In this study the gas used was nitrogen at static pressures of 0.2 up to 5 MPa and at flow velocities of 25 m/s up to 170 m/s. A special Nylon airbag, deployed from the tube wall into the pipe, was used to simulate the airbag inflation in a real pipeline. For this purpose a special gas filling system consisting of a gas generator with a reservoir volume of up to 500 cm³ which permits air pressures up to 17 MPa to be generated inside the airbag was developed at ISL. With a fast pyrotechnically opened valve the reservoir gas was released for airbag filling. The airbag inflation was triggered in such a way that it opened in nearly 3 ms into the pipe flow generated by the shock tube and continued for about 10 ms. For this application a special measuring chamber was designed and constructed with 20 measuring ports. Through two window ports, located one in front of the other, the airbag inflation could be visualized with up to 50 successive flash sparks illuminating a fast rotating film inside a drum camera. Pressure measurements using commercially available PCB pressure gauges at 9 measuring ports placed along the inner tube surface gave some hints on the behaviour of the wall pressure during airbag deployment. As a result from the experiments performed it is to conclude, that, with the Nylon airbag samples available, the pipe flow cannot be blocked by the inflating airbag. The flow forces acting on the airbag during deployment are in the shock tube experiments of the order of about 1000 N, which are not balanced by the airbags' neck, fixing it to the shock tube wall. This outcome suggests that a mechanical support is required to fix the airbag in its place during inflation.     

Estimates of fatal chest and abdominal injury prevention in side-impact crashes

The analysis reported in this study shows that the current NHTSA estimates of potential fatality reductions from improved side-impact protection in passenger cars are unrealistically high. This study is based on recent statistical estimates of fatality prevention by eliminating ejection and mitigating interior impact, and on an analysis of the limits of crash protection in fatal side-impact accidents. Because many fatalities involve high impact speed and significant deformation of vehicle side structures, about 70% of the near-side occupant fatalities from chest and abdominal injury are unpreventable by practical design changes. This implies that 30% of current fatalities may be prevented. Estimates of fatality prevention were then made as a fraction of the effectiveness of airbags in frontal crashes. Assuming sideinterior changes that may produce 20% of frontal airbag effectiveness, which is 6% effectiveness and is roughly the same level of safety benefit achieved with the energy-absorbing steering system, 140 fatalities per year would be prevented in all types of side-impact crashes. This estimate is a realistic but formidable goal. It is in striking contrast with NHTSA projection of 1,185 fatality reductions with relatively straightforward design changes. Their projection exaggerates potential safety improvements.     

Assessment of Integrated Pedestrian Protection Systems with Autonomous Emergency Braking (AEB) and Passive Safety Components

Objective: Autonomous emergency braking (AEB) systems fitted to cars for pedestrians have been predicted to offer substantial benefit. On this basis, consumer rating programs—for example, the European New Car Assessment Programme (Euro NCAP)—are developing rating schemes to encourage fitment of these systems. One of the questions that needs to be answered to do this fully is how the assessment of the speed reduction offered by the AEB is integrated with the current assessment of the passive safety for mitigation of pedestrian injury. Ideally, this should be done on a benefit-related basis.

The objective of this research was to develop a benefit-based methodology for assessment of integrated pedestrian protection systems with AEB and passive safety components. The method should include weighting procedures to ensure that it represents injury patterns from accident data and replicates an independently estimated benefit of AEB.

Methods: A methodology has been developed to calculate the expected societal cost of pedestrian injuries, assuming that all pedestrians in the target population (i.e., pedestrians impacted by the front of a passenger car) are impacted by the car being assessed, taking into account the impact speed reduction offered by the car's AEB (if fitted) and the passive safety protection offered by the car's frontal structure. For rating purposes, the cost for the assessed car is normalized by comparing it to the cost calculated for a reference car.

The speed reductions measured in AEB tests are used to determine the speed at which each pedestrian in the target population will be impacted. Injury probabilities for each impact are then calculated using the results from Euro NCAP pedestrian impactor tests and injury risk curves. These injury probabilities are converted into cost using “harm”-type costs for the body regions tested. These costs are weighted and summed. Weighting factors were determined using accident data from Germany and Great Britain and an independently estimated AEB benefit. German and Great Britain versions of the methodology are available. The methodology was used to assess cars with good, average, and poor Euro NCAP pedestrian ratings, in combination with a current AEB system. The fitment of a hypothetical A-pillar airbag was also investigated.

Results: It was found that the decrease in casualty injury cost achieved by fitting an AEB system was approximately equivalent to that achieved by increasing the passive safety rating from poor to average. Because the assessment was influenced strongly by the level of head protection offered in the scuttle and windscreen area, a hypothetical A-pillar airbag showed high potential to reduce overall casualty cost.

Conclusions: A benefit-based methodology for assessment of integrated pedestrian protection systems with AEB has been developed and tested. It uses input from AEB tests and Euro NCAP passive safety tests to give an integrated assessment of the system performance, which includes consideration of effects such as the change in head impact location caused by the impact speed reduction given by the AEB.     

基于GPS与GSM的交通事故自动呼救系统的设计

结合GPS的定位功能和GSM的远程无线通讯功能,提出一种以提高交通安全、减少人员伤亡为目的的车辆交通事故自动呼救系统的构建方案,该系统会伴随安全气囊的启动而启动,也可手动启动。车载模块将安全气囊点火信号送入微处理器,通过串行接口驱动无线数据传输模块,经GSM网络将GPS的定位信息发送到监控中心,并可建立车载模块与监控中心之间的语音通讯,给出车载模块硬件电路实现、软件设计以及控制中心的设计方案,并对系统的关键技术进行了说明。     

Airbag Technology in Australian Passenger Cars: Preliminary Results from Real World Crash Investigations

Airbags are expected to reduce vehicle occupant injuries, primarily by preventing head and chest contacts with the steering wheel and instrument panel. To date, however, there has been little evidence of airbag effectiveness in terms of field accident investigations. This paper presents some preliminary results from an ongoing case-control study of crashed vehicles equipped with Australian airbag technology (supplementary airbags in combination with seatbelt webbing clamps). Vehicles were inspected and occupants interviewed according to the National Accident Sampling System (NASS). Data were available for 140 belted drivers involved in frontal crashes (delta-V between 21 and 60 km/h), including 71 airbag and 69 control cases. Analyses revealed significant reductions in the cost of injury and a strong indication of a redaction in overall injury severity among the airbag cases. Indications of airbag benefits were also found in terms of a redaction in the probability of sustaining a moderate and severe injury. Some evidence was found for an increase in minor injuries among the airbag cases. As expected, airbag technology seems to be reducing head, face and chest injuries, particularly those of at least a moderate severity. These results are compared with recent overseas findings.     

Difference in dummy responses in matched side impact tests of vehicles with and without side airbags

Objective: Insurance Institute for Highway Safety (IIHS) high-hooded side impacts were analyzed for matched vehicle tests with and without side airbags. The comparison provides a measure of the effectiveness of side airbags in reducing biomechanical responses for near-side occupants struck by trucks, SUVs, and vans at 50 km/h.

Method: The IIHS moving deformable barrier (MDB) uses a high-hooded barrier face. It weighs 1,500 kg and impacts the driver side perpendicular to the vehicle at 50 km/h. SID IIs dummies are placed in the driver and left second-row seats. They represent fifth percentile female occupants.

IIHS tests were reviewed for matches with one test with a side airbag and another without it in 2003–2007 model year (MY) vehicles. Four side airbag systems were evaluated: (1) curtain and torso side airbags, (2) head and torso side airbag, (3) curtain side airbag, and (4) torso side airbag.

There were 24 matched IIHS vehicle tests: 13 with and without a curtain and torso side airbags, 4 with and without a head and torso side airbag, 5 with and without a side curtain airbag, and 2 with and without a torso airbag. The head, chest, and pelvis responses were compared for each match and the average difference was determined across all matches for a type of side airbag.

Results: The average reduction in head injury criterion (HIC) was 68 ± 16% (P < .001) with curtain and torso side airbags compared to the HIC without side airbags. The average HIC was 296 with curtain and torso side airbags and 1,199 without them. The viscous response (VC) was reduced 54 ± 19% (P < .005) with curtain and torso side airbags. The combined acetabulum and ilium force (7 ± 15%) and pelvic acceleration (?2 ± 17%) were essentially similar in the matched tests.

The head and torso side airbag reduced HIC by 42 ± 30% (P < .1) and VC by 32 ± 26% compared to vehicles without a side airbag. The average HIC was 397 with the side head and torso airbag compared to 729 without it. The curtain airbag and torso airbag only showed lower head responses but essentially no difference in the chest and pelvis responses.

Conclusion: The curtain and torso side airbags effectively reduced biomechanical responses for the head and chest in 50 km/h side impacts with a high-hooded deformable barrier. The reductions in the IIHS tests are directionally the same as estimated fatality reductions in field crashes reported by NHTSA for side airbags.     

自锁式管道内封堵装置结构与封堵性能分析

为了改进现有囊式带压封堵技术的防滑动效果差的缺点,提出了1种利用连杆机构与螺纹自锁实施止动的自锁式管道内封堵装置。探讨这种自锁式封堵与传统封堵的结构与性能,分别建立了波纹封堵气囊模型和光滑封堵气囊模型,并通过有限元仿真及实验分析,得出2种封堵气囊在0~0.35 MPa的充压条件下实施封堵的不同效应。结果表明:波纹封堵气囊的封堵压力比传统光滑封堵气囊的封堵压力高出约0.5 MPa,大大提升了管道内封堵装置的封堵能力,并且波纹气囊的形变主要分散在波纹中间,有利于缓解集中形变对气囊的破坏作用,最终提高了封堵实施的稳定性。该装置结构的性能分析可为应急救援装备的研制提供参考依据。