汽车驾驶座椅的人机工程学设计

根据汽车座椅舒适性的影响因素分析,结合并运用人机工程学对汽车座椅进行轻量化的改进,并按照国家法规进行汽车座椅的静强度分析.文中运用Pro/E进行建模,应用ANSYS有限元分析软件对座椅进行有限元分析.结果显示,汽车舒适型座椅由座椅的结构和座椅载荷分布情况确定.文中对座椅骨架的几何模型及有限元分析模型构建进行介绍.     

Optimum nose shape of a front-rear symmetric train for the reduction of the total aerodynamic drag

For a high-speed train, the same power car is used as the first car and as the last car in a reverse direction simultaneously. Therefore, the previously optimized nose shape, considering only the first car position, is not well adopted in the last car position of a front-rear symmetric train in view of the aerodynamic drag. The three-dimensional nose shape optimization of a front-rear symmetric train is conducted to minimize the total aerodynamic drag of the entire train using CFD. The 3-D nose model is constructed by the vehicle modeling function with the optimized area distribution to minimize the micro-pressure wave. It is revealed that the total aerodynamic drag of the optimum shape for the entire train is reduced by 23.0% when compared to that of the conventionally optimized shape only for the first car of the symmetric train.     

基于有限元的汽车安全带固定点的优化设计

根据国标对汽车座椅安全带固定点的要求,对汽车座椅安全带总成进行了CAD建模和CAE分析。分析结果表明:前排座椅安全带固定点可以满足国标要求,但后排座椅安全带固定点不能满足国标要求。故对后排座椅安全带的固定点进行了优化设计,并对改进后的结构进行了CAE分析。分析结果表明改进后的后排座椅安全带固定点可以满足国标的要求。     

A study on the design of a child seat system with mutipoint restraints to enhance safety

Currently, child seats are widely used as a child restraint system (CRS). The effects of CRS are experimentally investigated according to FMVSS213. In this paper, the dynamic simulation of a child seat is carried out using the LSDYNA software to develop an advanced CRS. A sled test using an existing child seat is first carried out, and the computer simulations using the LS-DYNA software are compared to the sled test to validate the dummy model and computer simulation. After matching the sled test and computer simulation results of a three-point belt-type child seat, a new type of child seat is developed with the computer simulation and optimization. For weight reduction, an optimization sequence is applied to determine the thickness of each part. For the area of stress concentration, reinforced members are added. The comparison between the simulation and the sled test shows good agreement, and the simulation results are proven useful for the further development of an advanced CRS.     

Simulations of the vibration response of mannequins in car seats by changing parameter and excitation

This study is based on previously developed tools for car seat designers. A simplified modeling approach to predict the vibration response, about an operating point, of mannequin occupied car seats is demonstrated to be feasible. A two-dimensional model, consisting of rigid bodies interconnected by pin joints with torsional dampers, springs and dampers had been developed. The springs and dampers are linear and the nonlinearity in the model is due to geometric effects, although at vibration levels experienced under normal driving conditions a linearized version of the model predicts responses. The effects of changing model parameters on the natural frequencies, the mode shapes and resonance locations in frequency response functions were shown in previous papers. Reasonable qualitative as well as good quantitative agreement between experimental and simulation frequency response estimates is obtained. Especially, k2 parameter, x-directional excitation and matching between the experiment and simulation are considered. The application of these simplified models is in car seat design, where they would facilitate evaluation of the effects of seat design changes prior to prototyping.     

基于MBS的剪式座椅垂向刚度特性比较分析

采用多体系统(MBS)动力学分析软件ProMECHANICA/Motion建立了剪式座椅悬架的仿真模型。基于此模型,比较了6种典型弹簧布置方式下的座椅垂向刚度特性,分析了2种典型弹簧布置方式下连接点位置变化对座椅垂向刚度特性的影响。仿真结果表明,多数弹簧布置方式下的剪式座椅垂向刚度具有明显的非线性特性,且其非线性特性在工作行程内表现为软特性,软特性的强弱程度随弹簧布置方式的不同而不同,弹簧倾斜布置于两剪杆之间或剪杆与座椅底板之间时,座椅垂向刚度软特性的强弱随弹簧连接点位置的变化而变化。     

基于简化模型的头车转向架气动噪声特性研究

由于高速列车气动噪声形成的机理和分析较为复杂,目前的检测系统还不能从列车高速运行状态下噪声测试中做出清楚的分辨,通过计算流体力学方法研究高速列车头车转向架气动噪声特性。建立经过简化的转向架、头车未安装转向架的简化车身和头车安装简化转向架的车身三种计算模型,分析列车运行200 km/h,300 km/h速度下简化转向架周围流场与气动声场特性,进一步分析此速度下简化转向架对头车车外气动噪声的影响。分析结果显示转向架周围有周期性的漩涡生成、脱落现象,气动噪声在其周围的辐射规律呈现偶极子分布。转向架车轴和构架横梁的上、下表面为偶极子声源集中的部位。前轮对在垂直与气流方向的竖直平面上和平行于气流方向的竖直平面上引起的噪声比后轮对大,在平行于气流的水平平面上比后轮对小。两个速度下,转向架气动噪声分布规律大致相同,幅值有差别。转向架使头车车外噪声显著增高,转向架附近噪声增幅尤为明显。行车速度200 km/h时,简化转向架能使头车车外气动噪声幅值增大3~5 d BA,行车速度300 km/h时,增幅为5~8 d BA。     

微车座椅面套的巧妙设计

重点阐述微车后排座椅护面总成的巧妙设计，在护面总成上设计了固定插销口袋，随车工具袋，解决了后排座椅固定插销带来的易脏与异响问题，同时也解决了车内凌乱和随车工具易丢失的问题。     

扰流板安装方向对高速列车的气动性能影响

采用结构网格对计算区域进行离散,采用DES湍流数值模拟方法,研究高速列车尾部横向、竖向或斜向地安装扰流板对车的气动性能影响,找出扰流板安装的合理方向。研究结果表明:安装横向或竖向扰流板后,尾部的气动阻力变大,升力减小,而安装斜向扰流板后,尾部的气动阻力与升力均减小。因此,列车尾部扰流板的合理方向为斜向安装。     

轿车八自由度平顺性动力学仿真与实验研究

建立了轿车八自由度平顺性动力学模型,推导了八自由度轿车模型拉格朗日方程,并应用仿真软件MATLAB/S imu link建立了轿车平顺性的仿真模型,对驾驶员座椅、副驾驶员座椅和后排左侧座椅的垂直加速度信号进行了仿真,得出了频域内的仿真结果,并与实验结果进行了对比。     

汽车儿童安全座椅的结构特点及发展趋势探讨

汽车儿童安全座椅也称儿童约束系统CRS（Child Restraint System）,正确使用它能够在交通事故中有效地保护儿童。我国儿童安全座椅使用率低,儿童安全相关法规缺乏,因此,研究汽车儿童安全座椅具有重要意义。笔者介绍了国内外汽车儿童安全座椅的研究现状,阐述了儿童安全评价体系及相关法规,并介绍了不同类型儿蕈座椅的结构特点及几种能更好保护儿童的新型汽车安全座椅。展望了在我国推广使用汽车儿童安全座椅所需解决的问题及其发展趋势。     

汽车座椅前座纵向调节性能检测设备的研制

针对汽车座椅前座纵向调节性能的检测要求,研究设计对国内大众、通用等汽车公司各类车型配套座椅具有广泛通用性的柔性化自动检测设备。基于机械设计、传感与检测技术的基本理论和方法,综合分析座椅性能指标,对检测设备的主体构成、工作原理、体现设备通用性的叠加式交叉导轨、可倾式工作台等关键设计进行了较详细的阐述和分析。该设备已成功应用于企业生产实际,提升了企业对产品性能的检测能力和水平,在提高生产效率,降低生产成本等方面取得明显成效。     

Train Vehicle Structure Design from the Perspective of Evacuation

The safety of trains,a highly efficient mode of transportation,has attracted significant attention.In the vehicle structure design of a train,the evaluation of the passenger evacuation time is necessary.The establishment of a simulation model is the fastest,most convenient,and practical way to achieve this goal.However,few scholars have focused on the reliability of a passenger train evacuation simulation model.This paper proposes a new validation method based on dynamic time warping and multidimensional scaling.The proposed method validates the dynamic process of a simulation model,provides statistical results,and can be used for small-sample scenarios such as a train evacuation scenario.The results of a case study indicate that the proposed method is an effective and quantitative approach to the validation of simulation models in a dynamic process.Thus,this paper describes the influence of the train structure size on an evacuation based on the results of simulation experiments.The structural size factors include the door width,aisle width,and seat pitch.The experiment results indicate that a wide aisle and reasonable seat pitch can promote a proper evacuation.In addition,a normal train door width has no effect on an evacuation.     

基于试验测试的桥梁与路堤区段高速列车车外噪声特性分析

高铁因线路形式不同使得其车外噪声特性有差异。为研究桥梁和路堤两种主要线路形式处的高速列车车外噪声特性,参考ISO 3095标准,使用78通道轮辐式声阵列、基于反卷积波束形成算法,对高速列车进行车外声源识别测试,使用自由场麦克风,对高速列车进行通过噪声测试,对比研究不同行车速度下两种线路形式处的高速列车车外噪声特性。结果表明,相同运行情况下,路堤段的通过噪声要比桥梁段的高0.1 dBA到1.8 dBA,且此差值会随列车运行速度的增加而增长。从车外声源分布特性来看,无论是桥梁段还是路堤段,300 km/h匀速运行时,高速列车的受电弓区域噪声均是最为显著的,其次是转向架区域。在桥梁段运行时,转向架区域噪声要略高于路堤段,这可能与桥梁段轨道整体刚度有关。在路堤段运行时,列车车身表面的噪声更大,这可能和路堤段的声音的地面反射有关。随列车运行速度的提高,两种线路对应的受电弓噪声差值逐渐减小,而转向架区域噪声的差值基本不随速度变化。     

基于高速铁路随机振动环境对人体腰椎影响的人机工程座椅设计

为了设计出更好的高速列车座椅,提高乘客的乘坐舒适度,针对国内高速列车设计标准在生物力学方面缺乏明确规定的问题,建立了人体腰椎L1~L5的有限元模型,并对模型的合理性进行了实验和理论验证。对不同坐姿下的腰椎模型进行了静态和350km/h高速列车运行环境下的动力学分析,计算腰椎静态和外部激励作用下的结构响应情况,为高铁座椅的人机工程设计提供依据。        

某型商用车司机座椅振动特性研究与优化

对某型商用车中的固定式座椅进行了传递特性研究,利用苏试电动振动台对座椅传递特性进行了试验,并建立了ADAMS动力学模型,利用试验数据验证了模型的准确性,并在此基础上进行了座垫刚度阻尼的优化,仿真表明优化后的座椅能在一定程度上改善座椅舒适度.     

中美校车座椅安全标准及试验方法对比

校车安全问题已经成为社会热点,座椅等关键部件的性能好坏对校车安全具有重要作用。国家新出台了专用校车座椅系统强制性检测标准GB24406,针对标准要求和试验方法,对国标GB24406与美标FMVSS222进行对比研究。结果表明:GB24406在座椅安装、抗后倾性能、座垫保持和固定件等方面参考了FMVSS222,在座椅抗前倾性能方面,采用了座椅动态试验,对座椅和约束隔板的实际安全性能进行评价,为国内校车安全标准体系的建立提供了支撑。     

全挂车形式叉车悬架弹性结构的优化设计

针对全挂车叉车原始样车的设计特点进行分析,指出原始设计的主要不足之处,提出一个旨在改善其高速行驶稳定性的悬架弹性结构修改方案。进而,将优化设计原理应用于悬架弹性结构的匹配设计领域。基于车辆系统的动、静力学分析,结合对整车高速行驶稳定性影响因素的讨论,建立相应的优化模型并进行求解,从而确定出能够满足整车高速行驶稳定性设计要求的悬架弹性元件的最佳刚度特性。最后,对优化设计的有效性加以检验。一方面,建立悬架系统与整车匹配分析的功能虚拟样机,对全挂车叉车在高速拖行状态下的稳定性进行仿真,结果表明：经过优化设计的全挂车叉车,其高速行驶稳定性获得了明显提高。另一方面,以优化设计结果为指导,完成了新一轮样车试制,并在实际道路条件下对优化前、后的样车进行高速拖行稳定性对比试验,结果同样表明：针对悬架弹性结构的优化设计,的确可改善整车的高速行驶稳定性。     

Noise and vibration on the bogie of a mass rapid train

This paper investigated a noise and vibration concern on a metro train while the train made turns. The study was conducted to identify the root causes of the vibration and noise through hardware experimental testing as well as dynamic computer simulation. The initial investigation indicated the noise came from the bogie of the train. It was between the slewing ring bearing and the friction sets. A lab test was established to duplicate the reported problem and to root out the causes. One-factor-at-a-time method was used to screen the main key factors. Under certain contact conditions, unsmooth turning would occur and cause the noise and vibration. Dynamic simulation was proposed in the study to predict the potential issue. A multibody dynamic model was built with train body, underbody, slewing ring bearing and friction set to simulate the train turning motion. The results showed unsmooth/discontinuous dynamic motions and torque oscillation behaviors. The stop-and-go and stick-and-slip motion led to the vibration. The analysis confirmed the unsmooth friction forces and adhesion could cause the noise and vibration. The computer simulation showed good correlation with the hardware testing. It demonstrated the computer dynamic simulation could be used to predict the potential friction induced vibration issues. In the study, a different substitute material was also investigated through the computer simulation. The results showed the vibration could be effectively reduced if ceramic compound friction material was used.     

基于伴随方法的高速列车头型气动优化

为改善高速列车明线运行时的气动性能,基于伴随方法和径向基函数网格变形技术,开展高速列车头型气动优化设计。采用径向基函数网格变形技术,避免列车头型优化过程中的网格重复生成,提高头型优化的效率。通过伴随方法求解目标函数对列车头型的敏感度,无须定义任何的头型设计变量,避免人为指定设计变量对优化结果的影响。将网格变形技术、伴随方法及计算流体动力学（Computational fluid dynamic,CFD）方法相结合,构建高速列车头型优化设计流程,选取整车气动阻力和尾车气动升力为优化目标,对高速列车头型进行多目标气动优化设计。结果表明：伴随方法可以有效地应用于高速列车的头型优化;优化后,在满足约束条件的情况下,列车的整车气动阻力减小2.83%,尾车气动升力减小25.86%;气动阻力减小主要位于头尾车流线型部位,中间车和头尾车车体气动阻力基本保持不变;尾车气动升力减小主要位于流线型部位,尾车车体向下的升力绝对值也有所减小。