基于关联图的车身零件装配序列规划

对车身零件装配优先关系应用装配关联图及矩阵建模,分析了装配不同构形下的分总成数学模型,根据识别出的分总成采取不同的选择方案以自动生成车身装配序列,该方法应用某车身前围进行了装配顺序规划的实例验证。     

柔性装配偏差分析在白车身焊装尺寸质量控制中的应用

针对汽车白车身焊装特点,介绍了一种柔性装配偏差分析方法,并利用该方法对某型汽车前舱总成焊装过程进行了模拟焊装试验.模拟试验结果表明,柔性装配偏差分析方法能够反映出实际焊装过程中零件尺寸偏差情况,并可通过敏感度分析快速找出产生问题的根本原因.通过实际应用验证了该方法的有效性.     

尾灯固定板和流水槽总成的工艺研究

介绍了白车身零件尾灯固定板和流水槽总成的产品特点和质量育成过程中的主要问题。通过改变总成冲压单件分割线位置、将侧围灯口型面分到单件流水槽的方法,规避了尾灯固定板开裂的工艺难题;介绍冲压件尾灯固定板和流水槽的工艺方案、主要工序的CAE分析结论和工艺要点。通过采用特制的焊钳、解决了零件焊接空间不足的问题,使零件焊接工艺可以采用点焊;通过在焊接夹具上设置铜垫板,解决了点焊带来的压痕、影响零件外漏表面质量。介绍了总成尺寸育成和装配过程中主要问题,并提出了整改方案及优化建议。     

白车身总成装焊尺寸精度控制方法探讨

在白车身总成装焊中,控制零部件定位尺寸精度偏差是关系到白车身总成装焊质量、汽车装配质量和影响汽车性能的重要因素.同时,也是影响白车身外观质量、装配效率和装配成本的关键问题.     

某车型组合尾灯缝隙匹配缺陷分析与改善

某车型组合尾灯外观匹配,两灯体间缝隙呈上大下小趋势,落差达2.0 mm,目视外观效果差。经对零件、钣金逐个进行测量,累计偏差值仍与实际状态存在较大差异,无法吻合。通过在标准检测主模型上对零件逐个装配、比较,发现在局部安装位置的设计余量无法满足实际的累计偏差,导致零件在实车装配时出现过约束,将偏差放大,是造成差异的主因。通过优化局部结构优化,释放公差累计,最终保证了组合尾灯缝隙匹配满足设计要求。通过此分析表明,对缝隙匹配的尺寸链分析中,除直接考虑偏差代数值累计外,还应考虑由于累计偏差导致的放大影响效果。     

定性仿真在车身概念装配设计中的应用研究

简述了公差设计、定性仿真及定性建模等方面的研究现状,并探讨了定性仿真在车身概念装配设计阶段的工程应用、定性装配的可行性分析与车身装配的定性公差分析描述。仿真系统对装配特征的物理参数进行了定性信息提取,通过定性分析确定装配过程偏差的主要影响因素。     

汽车总成维修装配原理

总成是由许多零件部组成，总成装配是总成修理工艺过程中的最后阶段，它是按规定的技术条件，将组成总成的零部件连接在一起。为了检验总成的装配质量，总成装配后应进行磨合与试验，以发现修理装配中的缺陷，提高配合副工作表面的承载能力。     

汽车车门总成装配压合模的设计

汽车车门总成的装配、合成品质，在一定程度上反映了汽车车身总成的制造水平，本文对两种不同类型车门的压合，采用摆板复合模和斜楔复合模的设计及结构要点作较详细的介绍。     

试论车身结构边界的确定

车身结构设计中的一个首要问题，是确定各构成零件的边界，因构成零件的空间特异性，边界条件复杂，不同的边界条件将产生不同的零件构成。焊接工艺、装配工艺以及模具工艺的多样性，造成了车身边界的不易确定特性；综合考虑上述因素的影响，才能确定车身结构零件的边界。文章中通过对某微型客车前围改进设计工作的实例的回顾、分析，阐述了车身结构零件边界的确定性、确定原则及要求。     

汽车尾灯周边外观配合关键影响要素分析与研究

尾灯周边外观配合的影响要素非常多,包括设计结构、单品精度、总成精度、车身精度、装配精度等,这些各汽车制造公司都已作为品质要点进行了管理,即便如此,仍无法完全保证尾灯周边外观配合,文章在上述常规要点管控基础上,基于设计配合结构、定位基准、制造工艺等多方面,分析了3项影响外观配合的关键要素。实践表明,解决这3项关键要素,能有效提高尾灯周边外观配合问题点的解决效率及品质稳定性。     

基于UG的汽车车身焊装夹具的三维模拟设计

以某汽车地板后纵梁总成焊装夹具的设计为例,介绍了汽车车身焊装夹具的结构特点和设计要点。阐述了基于UG三维建模平台的焊装夹具的设计方法,该方法可进行焊装夹具的三维结构设计、三维建模、虚拟装配、焊枪姿态模拟及二维出图等,生产成本及产品报废率低、设计周期短,可逐步取代传统的二维平面设计。     

燃料电池轿车碰撞安全性仿真研究

针对某一由普通轿车改装的氢燃料电池轿车,利用非线性有限元分析软件LS-DYNA,对其正面、侧面及后面碰撞进行仿真,分析了该燃料电池轿车相对于其原型车在碰撞安全性方面的变化,以及其部分高危零部件在碰撞中的表现,并做了相应的改进设计。最后总结出改装型燃料电池汽车在不同的工况下相对其原型车的碰撞安全性的变化趋势,为燃料电池轿车碰撞安全性设计以及相关法规的制定提供了依据。     

轿车车身主断面设计方法

论述了轿车车身主断面的设计流程,给出了典型的轿车车身主断面位置图。从断面基准定义、零件焊接面之间圆角半径确定、门洞法兰面相关参数确定、包边结构相关参数确定等方面,介绍了轿车车身主断面所表达的内容;并例举了前门、侧围上部、顶盖关系主断面,以及前门、后门、中支柱、后门铰链关系主断面的设计。     

整车试制阶段的电器故障诊断方法

以整车装车与跑车验证案例为背景，讨论汽车开发过程中汽车电器故障诊断的方法，阐述如何应用零部件置换原则来分析故障的重要性等级（significance）。     

基于CATIA的轿车后保险杠外板曲面设计与质量分析

针对某型轿车后保险杠外板曲面的结构特点,提出了一种基于CATIA V5的快速建模与曲面质量评价方法。该方法首先将外板曲面划分为主特征和附加特征,然后应用CATIA V5提供的多工作台混合建模功能,创建了轿车后保险杠外板曲面的三维模型,并结合A级曲面的定义与评价标准,应用多种曲面质量分析方法对后保险杠外板曲面质量进行了评价。该研究成果为轿车后保险杠优化设计提供高质量的数字化数模。     

Effect of the front and rear weight distribution ratio of a Formula car during maximum-speed cornering on a circuit

Because Formula cars are lighter than ordinary cars, the optimal settings for this type of car are thought to be different from those of a ordinary car. The front and rear weight distribution ratio of a vehicle is an important parameter that exerts a significant influence on critical cornering. The tendency of a ordinary car to under-steer during critical cornering is determined by the front and rear weight distribution ratio of the vehicle. Specifically, when the front of an ordinary FR (front-engine, rear wheel drive) vehicle is slightly heavier than the rear, the car tends to understeer during critical cornering. However, the optimal weight distribution ratio for critical cornering is not obvious for a formula car because of its lightness. This observation was investigated using a driving course similar to a real driving course to perform a maximum speed cornering simulations. It was found that a front to rear weight distribution ratio of 40:60 resulted in the fastest lap time. This ratio also gave the best results in the maximum-speed driving experiment performed using a driving simulator. Moreover, the maximum lateral acceleration during turning, the driving force, and the load movement of the inside and outside wheels was calculated using experimental driving force data and the concept of a tire friction circle. As a result, driving mechanics have been determined for a vehicle having a front/rear weight distribution ratio of 40:60 while traveling at maximum speed.     

基于仿真分析的轿车门框密封条装配结构改进研究

借助MARC有限元分析方法,对某款具有代表性的单泡管型门框密封条进行插拔变形和弯曲变形模拟分析.根据变形过程和仿真结果,确定原设计存在装配困难、容易脱落及弯曲塌陷等问题,并提出相应的改进方案.通过计算机仿真、零件性能测试和装车效果评价相结合的方法,验证了装配结构改进后的门框密封条在插拔性能和弯曲性能上均能满足设计要求.     

FSAE赛车悬架系统结构设计

为配合建立中国大学生方程式汽车大赛(FSAE)赛车的虚拟样机模型,根据FSAE赛事规则要求,对赛车悬架系统进行了结构设计。根据设计思路对轮辋、轮距及前后悬架立柱等相关部件进行了选择与设计,在确定采用不等长双横臂式悬架类型的基础上对弹性元件、减振器和导向机构的主要结构尺寸进行了设计计算,并应用软件Pro/E进行了三维建模设计,同时在SolidWorks环境下对前后摇块进行了强度校核。结果表明,前后摇块的最大合位移分别为4.260×10-3,2.838×10-2mm,最大变形均很小,设计的FSAE赛车悬架系统能够满足参赛要求,为进一步的实车研制提供了参考依据。     

基于改进图分解法的多材料车身结构优化设计方法

针对概念设计阶段的车身结构轻量化设计,提出了一种可实现车身多材料结构设计的分层迭代优化方法。该优化方法的设计变量中,除常见的板厚、材料外,还包括装配设计中的拓扑连接,以实现“将合适的材料用在合适的部位”的要求。分层迭代优化的第1层以拓扑连接为设计变量,采用图分解和NSGA-II对车身装配拓扑结构进行多目标优化,最大化车身弯扭刚度和1阶固有频率;第2层对板厚和材料进行多目标优化,最小化车身质量和材料成本。最终采用基于模糊集合的评分公式选定综合最优解,实现了考虑成本的车身结构轻量化设计。     

A mechanism to enhance bicycle conspicuity and visibility and increase detection distances: New insights into bicycle safety

Poor sensory conspicuity and poor visibility of bicycles are key factors that correlate strongly with bicycle-vehicle accidents. Although researchers have explored how to improve detection distances, i.e., the distances from which bicycles can be recognized by other road users, there is a dearth of research on ways to signal bicyclists' presence on the road. This study investigates how to enhance, at minimum cost, the level of visibility and sensory conspicuity of bicycles; it also considers ways to signal their presence to other road users, without necessitating any active behavior by bicyclists themselves. In the first study, the level of visibility of 6 rear-end components of bicycles was analyzed according to Adrian's model; the sensory conspicuity of these same components was analyzed via respondent perceptions in conditions of sunlight, twilight with no car headlights, twilight with car headlights, and night with car headlights. The level of visibility and sensory conspicuity of the 6 rear-end components were compared with considering angular size of the components under 4 lighting conditions. The level of visibility of the rear fender was good under sunlight and night-time conditions; in other conditions, the level of visibility was directly affected by painting the fender a silver color with reflectivity and also by the fender's angular size. However, the rear tire, among the 6 components tested, had a higher visible area when used with a short fender; it also produced rotational effects during riding conditions with no extra effort by the cyclists. In the second study, adhesive tape with specific patterns and 6 different color combinations were applied to the rear tire of a bicycle under the same lighting conditions, with the aim of creating a strong signal of the bicycle's presence for other road users. Among the 6 combinations, white stripes overlaid on the color red provide an optimal combination in terms of detection distance. The mean detection distance of white stripes on red in sunlight was 138.67 m, 94.67 m in twilight without car headlights, 94 m in twilight with car headlights, and 53.67 m at night with car headlights. In addition, this combination strongly signals the presence of the bicycle to other road users with no extra effort by the cyclists, thereby reducing the likelihood of drivers looking but failing to see bicycles. In sum, the study recommends that bicyclists install white stripes overlaid on red, in order to increase visibility and conspicuity and signal the presence of their bicycles, thereby reducing the likelihood of cyclist-vehicle collisions.