安全气囊对离位乘员的损伤及其改善措施的研究

详细介绍了基于计算流体力学的前排乘员安全气囊的建模方法;依据FMVSS 208法规,利用MADY-MO软件通过仿真模拟前排离位乘员和安全气囊的接触过程,对气囊造成伤害的机理进行分析;为减轻气囊对离位乘员的伤害,提出了可断裂式拉带安全气囊的改进方案,并对其改善效果进行仿真.结果表明该方案能较好地达到改善伤害的效果.     

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。     

Simulation of an airbag deployment in out-of-position situations

The commonly used 'uniform pressure method' (UP) is a well-tried method to simulate an airbag deployment in accident cases. Nevertheless, this method indicates rather heavy inadequacies at the examination of the airbag deployment in the first milliseconds. A solution is the airbag deployment calculation by using computational fluid dynamics (CFD) methods, wherein the calculated gas flow pressure may be applied 'correctly' to the airbag shell elements.

This CFD simulation is integrated in LS-Dyna with the so-called Arbitrary Lagrangian Eulerian (ALE) method and in this review the result's accuracy will be discussed. According to the FMVSS 208, an OoP model will be built-on and comparisons with simulations and tests are done. Another important detail in this labour is the airbag cover examination and the tear seam modelling, as a trivial FE modelling cannot be done due to the very fine mesh. So two possible solutions for tear seam modelling are introduced and discussed. Furthermore considerations concerning the gas generator combustion will also be revealed and an analysis about the impossibility of the direct comparison between gas generator tank test and airbag deployment will be done. At least some parameters, which take effects in the simulation, are researched and evaluated, so finally an optimised simulation model can be made available for further examinations.     

Analysis of bus rollover protection under legislated standards using LS-DYNA software simulation techniques

A bus rollover is one of the worst vehicle accidents that can occur. Because of the large numbers of passengers, the casualties in a bus rollover are often high and severe. The compliance with rollover safety standards for buses and coaches is mandated by law. This paper presents a comparative analysis of the physical meanings of regulation number 66 of the Economic Commission for Europe (ECE R66) and standard number 220 of the American Federal Motor Vehicle Safety Standards (FMVSS 220). This comparison was carried out using a LS-DYNA finite-element analysis. After performing a comparative analysis following ECE R66 and FMVSS 220 assessments, the investigation further demonstrated the distortion configuration of the vehicle superstructure through the absorbed energy and its distribution over the vehicle and in sections of vehicle superstructure as well as the violation of the passenger compartment under the rollover testing conditions of both ECE R66 and FMVSS 220. Great differences were found between ECE R66 and FMVSS 220 in distortion configuration, reflecting differences in capability and rollover testing conditions. These findings provide a means of evaluating bus superstructure strength and provide guidelines useful in the assessment of regulations applied to the evaluation of bus rollover strength.     

某车型FMVSS214与E-NCAP侧面柱碰撞差异

侧面柱碰撞是新车评价规程中的重点考察项目.从试验工况、车体响应及假人伤害等方面对比了FMVSS 214侧面柱碰撞与E-NCAP侧面柱碰撞的差异性,分析2种试验假人易受伤害的部位及原因.经验证,2种碰撞试验可以使用同一点火策略;由于FMVSS 214侧面柱碰撞速度更高,碰撞位置更靠前,要求侧气囊保压时间更长,覆盖面积更大,建议使用带主动泄气孔的产品,并加强车门结构,以降低对假人胸部、腹部以及骨盆的伤害.     

现代汽车安全气囊技术

安全气囊作为辅助的乘员约束系统,主要用来防止乘员在前碰撞事故中与驾驶室内饰件的二次碰撞。本文根据安全气囊对乘员不同身体部位进行的保护,详述了不同位置汽车安全气囊的功能、结构和ECU对安全气囊的时间控制,并对汽车安全气囊技术的发展趋势进行了简要阐述。     

Occupant position detection system (OPDS) for side airbag system

In order to prevent injury of the occupant of the passenger seat when a side airbag deploys, we have developed an occupant position detection system. It detects the occupant's head entering the side airbag deployment zone. If so, the side airbag operation is inhibited and an indicator light on the side airbag alerts the occupant to the improper sitting position. It detects accurately the occupant's size and the head entering the side airbag deployment zone, using an occupant identification algorithm and electrostatic capacity sensors under the seat trim cover which determine the dielectric around the seat surface.     

特别报告：安全气囊——随着安全气囊成为新型汽车的一个标准特征，汽车制造厂家正在开发新的技术以进一步改善其安全性能

第一个汽车用安全气囊在二十世纪七十年代出现于美国的通用公司的汽车上。在欧洲，Morton公司即现在的奥托利夫公司，在1980年在s级的默西迪丝一奔驰汽车上引入了一种驾驶员安全气囊。本田汽车Acura Legend在1987年成为第一辆安装了一个安全气囊的日本车，从此，安全气囊装备的速度在世界范围内迅速增长。     

便携式安全气囊诊断仪的设计与研究

设计一种便携式安全气囊诊断仪,它具有通用的通信方式,能够对现有的QH3-F以及QH4-OCS等系列气囊系统进行诊断,诊断结果真实可靠。     

Brazil’s new vehicle front impact safety standards — ABNT NBR 15300-1 & ABNT NBR 15300-2 or ABNT NBR 15300-3: Is the manufacturerer choice the safest for the passenger?

To increase car passenger safety, the Brazilian National Traffic Council (CONTRAN) released Resolution 221, which defines the maximum passenger and driver biomechanical criteria in the event of a vehicle frontal impact. The vehicle maximum allowed biomechanical injury criteria will be enforced from January 2012 for new vehicles and in January 2014 for vehicles in production before January 2014. To standardize the test method to measure the driver and front passenger injury values in a frontal crash, Resolution 221 states that the tests must be performed according to the ABNT NBR 15300-1 standard, followed by the ABNT NBR 15300-2 standard or the ABNT NBR 15300-3 standard. The use of ABNT NBR 15300-2 or ABNT NBR 15300-3 standards is a free choice for the manufacturer of the vehicle. The ABNT NBR 15300-1 + 15300-2 test is similar to the FMVSS 208 standard in the United States in terms of its vehicle frontal impact test perpendicular to a rigid barrier with the use of seat belts by male model dummies. The test according to ABNT NBR 15300-1 + 15300-3 follows the European ECE R94 and 96/79/EC standards. However, ABNT NBR 15300-2 focuses on occupant protection during vehicle deceleration rather than occupant protection during vehicle deformation in a crash test. ABNT NBR 15300-3 tests occupant protection during vehicle deformation more than it tests occupant protection during vehicle deceleration. Therefore, this paper aims to show the types of test results produced by the ABNT NBR 15300-2 and ABNT NBR 15300-3 standards and their differences concerning occupant protection verification and discuss the manufacturer??s freedom of choice.     

基于有限元方法的气囊展开模拟及对乘员安全性的影响

本文从乘员安全性角度出发,在LS-DYNA软件的基础上,介绍了安全气囊展开模拟的两种数学模型:均匀压力模型和计算流体模型。介绍了利用VPG软件折叠安全气囊的方法,对不同数学模型的展开结果进行了比较。此外,本文还研究了有无安全气囊对乘员安全性的影响。     

基于虚拟试验方法的气囊折叠方式对离位乘员损伤影响的研究

基于MADYMO软件建立了对称折叠和环向折叠安全气囊以及假人碰撞位置的虚拟试验模型。试验结果表明：环向折叠气囊对人体的主要损伤值都小于对称折叠气囊的相应值;试验中测得的所有损伤值都小于损伤评定参考值,并和有关实际试验的结果基本相同。虚拟试验是一种研究气囊折叠方式对离位乘员损伤影响的有效方法。     

芜湖长江公铁大桥2号墩围堰气囊法下水设计

为给双壁钢套箱围堰气囊法下水施工组织设计提供理论支撑,以商合杭铁路芜湖长江公铁大桥2号主墩圆端形双壁钢套箱围堰为例,研究双壁钢套箱围堰气囊法下水的设计方法。结合围堰拼装场地地形条件进行坡道与气囊布置并进行后端地笼计算。将围堰下水过程分解为多个工况进行静力计算,在计算过程中考虑气囊受力不均对围堰角度的修正。运用能量守恒原理简便求解围堰下水时的初速度和围堰入水后的漂移长度。采用该方法指导芜湖长江公铁大桥2号主墩围堰下水,过程顺利、可控,证明该方法正确可行。该方法可同时适用于圆形、矩形、哑铃形等各类双壁钢套箱围堰气囊法下水设计。     

Analysis and optimization of air suspension system with independent height and stiffness tuning

Suspensions play a crucial role in vehicle comfort and handling. Different types of suspensions have been proposed to address essential comfort and handling requirements of vehicles. The conventional air suspension systems use a single flexible rubber airbag to transfer the chassis load to the wheels. In this type of air suspensions, the chassis height can be controlled by further inflating the airbag; however, the suspension stiffness is not controllable, and it depends on the airbag volume and chassis load. A recent development in a new air suspension includes two air chambers (rubber airbags), allowing independent ride height and stiffness tuning. In this air suspension system, stiffness and ride height of the vehicle can be simultaneously altered for different driving conditions by controlling the air pressure in the two air chambers. This allows the vehicle’s natural frequency and height to be adjusted according to the load and road conditions. This article discusses optimization of an air suspension design with ride height and stiffness tuning. An analytical formulation is developed to yield the optimum design of the new air suspension system. Experimental results verify the mathematical modeling and show the advantages of the new air suspension system.     

实车碰撞试验法规的现状和发展趋势

实车碰撞试验法规主要有美国的FMVSS和欧洲的ECE两大体系，下面碰撞试验法规为FMVSS208、E-CER94，侧面碰撞试验法规为FMVSS214、ECER95，在我国，汽车被动安全性一直是汽车产品较薄弱的环节之一。1999年，我国颁布了第一项汽车技术法规，CMVDR294《关于正面碰撞乘员保护的设计规则》。CMVDR294的颁布表明，我国政府已对汽车的被动安全性有了更全面的评价方法。     

基于提高乘员保护效能的安全气囊折叠方法研究

提出了安全气囊展开特性的优化指标。使用LS-DYNA软件建立了不同折叠方式的气囊有限元模型,结合静态点爆试验和图像处理技术,对一种新型气囊在典型折叠方式下的展开特性进行了分析。以模拟计算结果为依据,设计了基于提高乘员保护效能的新折叠方法。经试验验证,新设计的折叠方法具有良好的展开特性。     

汽车车外安全气囊技术探讨

为了提高对行人的安全保护,减轻或避免汽车碰撞损失,各国都在进行车外安全气囊的研究开发。文章参考大量数据与文献,介绍了国内外气囊技术的发展现状,详述了不同位置的车外安全气囊的结构、功能,分析得出未来汽车安全气囊的发展趋势及开发难点。随着安全气囊技术的成熟,未来汽车安全化、人性化的发展趋势,安全气囊的保护范围也将进一步扩大。     

基于任意拉格朗日-欧拉算法的气帘展开数值模拟

大多数气囊展开模拟采用均匀压力算法,为了更有效地模拟充气气体与袋体的相互作用,建立了基于任意拉格朗日-欧拉算法(ALE)的气帘仿真模型,详细介绍了ALE模型相关组成部件、参数设置和接触定义方法,并利用LS-DYNA软件对该模型进行了仿真验证,最后将所建的气帘ALE模型初步应用到某车侧面碰撞仿真中,以考察气帘对乘员的保护作用.     

Stereovision-based real-time occupant classification system for advanced airbag systems

Occupant classification in a passenger seat is one of the critical components for any advanced airbag system. Many automotive electronic suppliers and engineers predict that the camera will be the next generation sensor for active and passive safety systems because it has several advantages compared to other sensors. The present paper describes a stereovision-based occupant classification system (OCS) and intelligent algorithm with embedded system by which triggering of the airbag deployment can be controlled. The system consists of a pair of stereo cameras and dual Digital Signal Processor (DSP): the first DSP is for the stereo matching processing, and the second is for occupant classification. The results show that the reaches 97%, and the processing time is 960 ms. Such performance indicates that the feasibility of the system as an embedded OCS is high.     

碰撞试验中侧气囊对假人头胸部的保护效果

侧面安全气囊和气帘是专门针对乘员进行保护的安全装置,在发生侧面碰撞的交通事故中能有效地减少乘员受伤害的程度.文章从2013年在国家轿车质量监督检验中心进行的,依据GB 20071-2006《汽车侧面碰撞的乘员保护》进行的侧面碰撞试验中,选取了10个车型,包括轿车和SUV,每个车型分别进行了有侧面安全气囊、气帘和没有侧面安全气囊的侧面碰撞试验,结果表明配备侧面气囊和气帘的汽车能对乘员头部和上部肋骨提供更好的保护,但对中部和下部肋骨的保护效果一般,可以看出侧面气囊和气帘能对乘员头胸部提供更好的保护.