DFMA在汽车工业中的应用

本文介绍了制造，装配的设计（ＤＦＭＡ，ＤｅｓｉｇｎｆｏｒＭａｎｕｆａｃｔｕｒｉｎｇａｎｄＡｓｓｅｍｂｌｙ）的基本原理，讨论了基于并行工程的ＤＦＭＡ在汽车工业中的重要意义和实施方法。     

重庆市双桥区乙型肝炎调查研究

对重庆市双桥区各行业人员进行乙型肝炎的流行病学调查，ＨＢｓＡｇ检出率为６．９９％，饮食服务行业的检出率为１４．８％，５０便ＨＢｓＡｇ阳性以作了两对半，其中４０－５６％病人的ＨＢｓＡｇ，－ＨＢｅ、－ＨＢｃ均为阳性，调查１２个ＨＢｓＡｇ家系成员，发现ＨＢｓＡｇ家系感染阳性率为６０．７％。     

用Access97实现组合条件查询的一种方法

在管理信息系统的设计中，组合条件查询是经常会遇到的问题。文章介绍了在Ａｃｃｅｓｓ９７环境下用ＶＢＡ编程实现的一种方法，具有很强的灵活性和实用性。     

中型载重汽车可靠性与维修性统计分析

本文对两种典型的国产中型载重汽车ＥＱ１４０和ＣＡ１４１的可靠性和维修性作了统计分析。结果表明：ＥＱ１４０的平均故障间隔里程ＭＴＢＦ约为１７７６ｋｍ，平均修复时间ＭＴＴＲ约为１０．３９ｈ；ＣＡ１４１的ＭＴＢＦ约为１８２１ｋｍ，ＭＴＴＲ约为９．８８ｈ。两种汽车的最薄弱总成均是发动机，而最难维修的则分别是ＥＱ１４０的后桥和ＣＡ１４１的变速箱。上述结果可供制造与使用部门参考。     

节流式磁流体阻尼可调减震器的试验研究

本文介绍了以两种不同的磁流体作为工作液的节流式磁流体阻尼可调减震器的外特性试验，试验结果表明：其中ＢＨ－１磁流体的粘－磁性能和粘－温性有均优于０６－Ａ，满足了磁流体阻尼可调减震器的性能的要求，节流式磁流体阻尼可调减震器的示功图饱满，阻尼力变化显著，可调性能优良；其结构合理，为实用型磁流体阻尼可调减震器的研究奠定了良好的基础。     

隧道工程中的三维动画制作

计算机辅助设计系统被认为是工程管理的必备工具。如今，ＣＡＤ已用于ＴＢＭ施工，送设备，混凝土提升设备的设计工作以及总体性能检查。一般地说，这种ＣＡＤ模型仅是二维模型。     

进口汽车常见英文缩写

缩写词英文全称汉语全称ＲＲ＆Ｍｒｅｌｉａｂｉｌｉｔｙａｎｄｍａｉｎｔａｉｎａｂｉｌｉｔｙ可靠性与维修方便性Ｒ．Ｔ．ｒｏｏｍｔｅｍｐｅｒａｔｕｒｅ室温ＲＡＭｒａｎｄｏｍａｃｃｅｓｓｍｅｍｏｒｙ随机存取存储器ＲＤＳｒａｄｉｏｄａｔａｓｙｓｔｅｍ无线电数据系统ＲＥ／ＲＤｒｅａｒｅｎｇｉｎｅ／ｒｅａｒｄｒｉｖｅ后置发动机一后轮驱动ＲＯＭｒｅａｄｏｎｌｙｍｅｍｏｒｙ只读存储器ＲＳｒｕｂｂｅｒｓｐｒｉｎｇ橡胶弹簧ＲＶｒｅｌｉｅｆｖａｌｖｅ安全阀，减压阀ＳＳＩｓｐａｒｋｉｇｎｉｔｉｏｎｅｎｇｉｎｅ点燃式发动机…     

用MDT实现弯管夹具CAD系统

介绍了在Ｍｅｃｈａｎｉｃａｌ Ｄｅｓｋｔｏｐ软件中，如何利用Ａｕｔｏ ＬＩＳＰ语言中对实体数据库的访问、表处理、３Ｄ从标变换等功能，以及Ｄｅｓｉｇｎｅｒ参数化造型技术。阐述了模拟弯管夹具设计过程、参数的计算设计，并采用３Ｄ参数化图形库组装结构总图，为投影关系复杂的２Ｄ结构设计图的生成开辟了一条有效的途径。     

基于ANSYSWorkbench减震器支架组有限元分析

详细介绍了减震器支架组有限元分析时的模型前处理、边界条件设定及后处理等分析过程，并通过对减震器支架组的应力分析结果进行的评判，系统分析了该减震器支架组在不同载荷下的适用情况。     

机械零件的网络计算机辅助设计

从机械制造过程的复杂性和多变性入手论述了机械ＣＡＤ和机械ＣＡＭ的难度，闻明了机械零件ＣＡＤ对零件的制造方法和过程的信赖性。结合美国Ｕｎｉｖｅｔｓｉｔｙ ｏｆ Ｃａｌｉｆｏｒｎｉａ ａｔ Ｂｅｒｋｅｌｅｙ的研究成果，并针对我国的国情，论述了在Ｉｎｔｅｒｎｅｔ上开展ＣＡＤ／ＣＡＭ的途径。希望能为我国机械制造业ＣＡＤ／ＣＡＭ的发展起到积极推动作用。     

一种新型汽车减振器优化设计方法研究

在对磁流变液减振器理论模型进行分析的基础上,确定了影响磁流变液减振器性能的结构参数。将磁流变液的非线性磁特性与非牛顿流体力学性能相结合,建立了以降低磁流变液减振器响应时间常数、增加其调节比为目标函数的优化模型。根据优化结果,研制了一种新型车用磁流变液减振器,并进行了验证试验。     

基于多体动力学的摩托车减振系统参数研究与优化设计

发动机和路面激励是摩托车的主要振动源,合理设计摩托车减震器的刚度和阻尼,对改善骑乘舒适性和安全性有重要意义.运用ADAMS软件建立125 mL摩托车模型,并对前后减震器参数进行优化计算,以求得到最好的减振效果.     

汽车筒式液阻减振器技术的发展

分析了汽车乘坐舒适性／行驶平顺性和操作稳定性对筒式液阻减振器特性的要求，提出汽车在不同行驶工况减振器特性的要求是不的；分析了被动式减振器的发展历程及非充气和充气减振器的特点，阐述了机械控制式可调阻尼减振器，电子控制式减振器以及电流变和磁流变液体减器等的结构特点，工作原理及其动态特性；分析了筒式液阻减振器其于经验设计／实验修正开发方法的缺点，阐述了基于CAD／CAE技术的现代设计开发方法的过程及其关键问题，最后分析了我国筒式液阻减振器技术的发展状况及问题，展望了减振器技术的发展前景。     

Full vehicle simulation using thermomechanically coupled hybrid neural network shock absorber model

In the case of full vehicle models, the technique of multi-body simulation (MBS) is frequently used to study their highly non-linear dynamic behaviour. Many non-linearities in vehicle models are induced by force elements like springs, shock absorbers, bushings and tires. Commonly, spline functions are used to represent the force responses of these components. If the non-linear relationships are more complicated, the spline approximations are no more accurate. An alternative approach is based on empirical neural networks which are based on the mathematical approximation of measured data. It is well known that neural networks are able to represent and predict complex component responses accurately. The aim of this paper is to perform a dynamic full vehicle simulation using a thermomechanically coupled hybrid neural network shock absorber model. In this shock absorber model, the spline approach is combined with a temperature-dependent neural network. Based on a displacement-controlled excitation on a four post test rig in the ADAMS/Car MBS software, a rugged test track is simulated. In this way, the front and rear shock absorbers are dynamically loaded with comfort-relevant frequencies in the range of 0.75–30 Hz and velocity amplitudes up to 2 m/s. By the simulation, stability of the hybrid neural network model is demonstrated. Furthermore, the damping force, the vertical acceleration of the chassis and the required simulation times are compared. The standard spline approach is used as a reference.     

Full vehicle simulation using thermomechanically coupled hybrid neural network shock absorber model

In the case of full vehicle models, the technique of multi-body simulation (MBS) is frequently used to study their highly non-linear dynamic behaviour. Many non-linearities in vehicle models are induced by force elements like springs, shock absorbers, bushings and tires. Commonly, spline functions are used to represent the force responses of these components. If the non-linear relationships are more complicated, the spline approximations are no more accurate. An alternative approach is based on empirical neural networks which are based on the mathematical approximation of measured data. It is well known that neural networks are able to represent and predict complex component responses accurately. The aim of this paper is to perform a dynamic full vehicle simulation using a thermomechanically coupled hybrid neural network shock absorber model. In this shock absorber model, the spline approach is combined with a temperature-dependent neural network. Based on a displacement-controlled excitation on a four post test rig in the ADAMS/Car MBS software, a rugged test track is simulated. In this way, the front and rear shock absorbers are dynamically loaded with comfort-relevant frequencies in the range of 0.75-30 Hz and velocity amplitudes up to 2 m/s. By the simulation, stability of the hybrid neural network model is demonstrated. Furthermore, the damping force, the vertical acceleration of the chassis and the required simulation times are compared. The standard spline approach is used as a reference.     

汽车磁流变非线性悬架模糊控制

建立了整车悬架系统的三维模型,根据试验数据得出了前后悬架弹簧的非线性特性曲线。前后悬架减振器均采用磁流变减振器,采用Bouc-Wen参数化模型为其阻尼力模型。采用模糊控制算法为整车半主动控制算法,采用ADAMS和Matlab联合对整车平顺性进行仿真。结果表明,采用模糊控制算法控制磁流变非线性悬架可提高整车的平顺性。     

摩托车减震器道路振动对比试验研究

将2款不同示功特性和速度特性的减震器分别安装在同一辆摩托车上,并在典型坏路面、石块路面和平直路面上进行了振动对比测试,并按ISO 2631标准要求,对摩托车脚踏位置、座垫位置进行了分析计算及舒适性评价;对立管中部的振动响应进行了对比,为摩托车道路振动的测试和评价提供了参考。     

Design of electromagnetic shock absorbers for automotive suspensions

Electromechanical dampers seem to be a valid alternative to conventional shock absorbers for automotive suspensions. They are based on linear or rotative electric motors. If they are of the DC-brushless type, the shock absorber can be devised by shunting its electric terminals with a resistive load. The damping force can be modified by acting on the added resistance. To supply the required damping force without exceeding in size and weight, a mechanical or hydraulic system that amplifies the speed is required. This paper illustrates the modelling and design of such electromechanical shock absorbers. This paper is devoted to describe an integrated design procedure of the electrical and mechanical parameters with the objective of optimising the device performance. The application to a C class front suspension car has shown promising results in terms of size, weight and performance.     

Investigation of Cavitation Process in Monotube Shock Absorber

The paper investigates cavitation effect which negatively influences the performance of a monotube shock absorber of road vehicle (passenger car). For better understanding of this phenomena, three physical models of shim stack valves are analyzed. Validation results allowed selecting the most appropriate valve model in presence of cavitation processes. A mathematical model of monotube damper with consideration of fluid compressibility and cavitation phenomena is developed. Simulation results are validated by experimental data obtained on hydraulic test rig. Based on the selected approach, a simplified method suitable for assessment of cavitation processes in automotive monotube shock absorbers is proposed. After investigation it is found that damping force when cavitation occurs mainly depends on the initial pressure and absorber inner diameter.