文献翻译-悬架性能测试

悬架性能测试悬架系统虽不是汽车运行不可或缺的部件，但有了它人们可以获得更佳的驾驶感受。

简单的说，它是车身与路面之见的桥梁。

悬架的行程涉及到悬浮于车轮之上的车架，传动系的相对位置。

就像横跨于旧金山海湾之上的金门大桥，它连接了海湾两侧。

去掉汽车上的悬架就像是你做一次冷水潜泳通过海湾一样，你可以平安的渡过整个秋天，但会疼痛会持续几周之久。

想想滑板吧！它直接接触路面你可以感受到每一块砖，裂隙及其撞击。

这简直就是一种令人全身都为之震颤的体验。

当轮子滑过路面时，就会在此产生震动，冲击，这种震动的旅程时对你的身体和勇气的检验。

如果你没感到随时都有被掀翻之势，那么你或许会乐在其中吧！这就是你会在没有悬架的汽车上将会体验到的。

为了道路交通安全，包括定期检查车辆暂停行驶性能测试是顺理成章的事。

原型试验结果与机载和规格提出有效悬架系统的测试。

示威活动是由欧洲减震器制造商协会(EUSAMA)，正确运作减震器已经引起了许多国家重视.。

估计英国早在1977年1月起，环境部就进行了检查减震器的MOT测试。

现在减震器机车里的测试仪器，就其实质效力及安全的客观评价就没有达到共识.。

但人们认为，欧洲可能用更严厉的法律手段定期检验将来的一种客观需求测试设备无法解释的错误。

自1971年成立，EuSAMA就认识到了该问题的重要性，并组成了最初的技术小组，负责研究和分析测试仪器。

有两个基本类型的机器提供了当时减震器故障诊断。

包括：1. 吊机，在轴的车轮约100毫米处，然后让它们落下。

接着记下他们各自的位置，然后和预定的前方或后方车辆暂停位置比较。

这种模拟机向前迈了一大步，并记录了实体运动情况(参看图1).这些措施调动机轮，引发暂停，从上述共振频率为零位置扫描。

采用了支持平台下的轮胎.。

成绩记录结果与车轮时间不符。

同时，把车轮弹跳沉最高频率和前方或后方的特殊车辆预定暂停位置进行比较。

下面要介绍的第三种机器，通过应用组件的平台下轮胎，引发了暂停或不断的频率阶段措施。

时刻激励部队记录结果，并和特殊车辆预定的暂停位置比较。

这些系统有三个基本的缺点：Ａ.与原来的阻尼表现比较而言，实际的阻尼出现了一定的退化。

原来的表现，已经是在边缘了。

Ｂ.设定上限的问题，即应该由谁来定限额的标准应该是什么呢? 目前在实践中设定的范围和可接受表现之间几乎没有任何关系Ｃ.对不同类型的车辆的悬架系统和实际存在的各种各样的中断，它们的界限会有所差别。

这就需要全面参考手册并不断更新。

尽管该系统有这些根本的弊端，但是他们的根特大学实验室工程师，以及几位Eusama成员已经开始使用测试仪器。

正如所料，第一个结论是，没有检验方法是可以不包括拆除汽车减震器就能够提供有关资料和减震器单的，但实际上整个汽车停止系统是通过了测试.。

这可以说是一个积极的方面测试，全部停止安全状况应当是良好的；尽管减震器最有可能进一步部分使用恶化，其他缺点如夸大轮胎，或处理破城球，如果可能的话，应给予诊断。

其他影响测试结果的因素中，气温减震器影响所有机器给出的结果。

对于下降型试验机减震器缺陷造成的高频激励是不能察觉的。

频率扫描型机器的出现，持续的投入意味着在用软或硬中断的车辆之间差别很大。

因此从太空正常到重型任务的改变(操作可能无法识别)可以认为直接影响结果。

每一种机器的制造都有它自己的特征，但由于基本原则，被认为是不可接受的测试不会在这里出现。

充分考虑技术小组委员会建议Eusama的加入，虽然现有机器正确操作，可以诊断许多错误减震器、负责协会不能批准这种设备作为技术上代表某一方面性能的衡量参数。

以刹车测试为例，指出：测试仪器直接显示制动效率的百分比，无需辨别车型或使用参考手册.。

同样，制动性能的最低水平也一定能为所有模式汽车使用，让顾客立即知道刹车注意事项，有些机器显示制动失衡，但并不表明它的某组成部分失常。

运用车辆停止同样的原则，应当可以提供测试，给出直接显示或最好的百分比，说明从安全角度暂停是不是可取。

进一步说，必须客观的执行，也就是说，测试者不需要任何辨别、说明、和参考手册。

因此技术小组寻找了一个合适的参数，可以视为车辆安全暂停标准。

如前所述，只有一个正常的组成部分那就是使用减震器。

首先必须确定减震器的作用。

它们可以实现两种功能：降低车身移动和控制车轮乱跳。

允许车身移动是一个很值得尝试的问题，主要是控制这些移动，在优化舒适方面，减震器的阻尼特性是不同的。

车身的移动当然影响到交通堵塞，但实际上很少有普通司机能达到范围内，所以对安全措施而言，车身的阻尼特性变得不那么重要。

在任何情况下，汽车阻尼性能差的司机可以很快控制速度，保证车辆的反应能力。

从另一方面来说，车轮弹跳是衡量危险的一个现象，车轮固定不牢固的危险是众所周知的。

两站和制动性能也是一样。

两站的轮胎和制动性能要收到道路情况的限制； 这是依靠纵向的联系,以及车轮轮胎资自身的性能。

道路交通堵塞的一个客观衡量标准，即车辆暂停安全性被独立出，但是仍需能够体现它可以随时解释。

有人提议，轮胎和公路间的纵向联系，车轮跳动次数，表示这是一个静态的车轮负荷百分比.。

这种可能性曾在会晤技术小组委员会和根特大学的Verschoore 博士讨论过，并达成了一些一致意见，但是一些成员仍表示怀疑这个测量参数实用性，以及怀疑相关结果。

在以后的小组中获悉，德国机械原型大概用上述原则提出了对根特大学的评价。

某些建议进行了修改后，根特大学和Eusama 公司成员证明了这种测试的可能性，充分证明了技术小组委员会要衡量参数的的决定。

下面是有关原型机器测试的过程和测试结果，由西德的Maschingfabrik Koppern 和 Co, Hattingen 发展，比利时布鲁塞尔的门罗提出。

车轮转动是由暂停引发的，扫描频率范围为0－25赫兹，在轮胎下方使用，伴随有固定6毫米的中风转动。

一次测试一个轮胎。

计算公式：100% 最小轮胎载重静止时在重．测试者所分析的结果会通过最小轮胎受力预示展现出来明显特征。

注重测试时的仪器读数和以往的实验经验相匹配，因为还没有一种科学的测试方法能够很精确的用在道路行驶测试系统上．最终决定车辆的行驶平顺性和乘座舒适性取决于车辆制造商所做的或多或少的行驶试验．测试方法是否能行将在于悬架系统是否正常工作，因此，推荐仔细的检查悬架系统的每一个单元以次来改进悬架测试的精确性，初始的错误可以经常被找到在测试恶化之前．第二，这悬架系统的测试，车轮与车轮之间，只有当有毛病时才表现出来；它并不规定这些错误，通过一个熟练的操作者可能从测试读本上诊断出一些毛病．很明显在设计一个机器时我们应考虑到存在一定机率过度静摩擦，仍然需要在这一领域的改进工作．当加强和改进弹簧和减振器时，汽车悬架的基本设计并没有同步进行，也没有什么重大革命性的发展。

但是这一切都随着BOSE公司的悬架品牌的引入而发生改变--就是那个在声学因发明创造引以为名的公司。

一些专家已经在说—BOSE的悬架是自汽车技术引入全独立悬架以来在汽车悬架的最重大的进步。

它是怎么工作的呢？BOSE的系统是在每一个车轮上装一个线控电磁马达（LEM）以控制一组减振器和弹性元件的状态。

功率放大器提供电力对马达在这种情况下他们的力量再生以系统的各压缩。

马达的主要好处是, 他们因具有惯性，不限制于固有的在常规基于流体的阻尼特性。

所以，一个LEM可以在任何的速度伸张和压缩，自然它可衰减乘员舱体的所有振动。

轮子的运动可以被很好的控制，因而，在轮子的任何运动状态车体都可以保持可以接受的状态。

LEM同样可以在汽车加、减速，转弯时产生的倾角较小，让驾驶员以更好的状态驾驶汽车。

Suspension performance testingThe suspension system, while not absolutely essential to the operation of a motor vehicle,makes a big difference in the amount of pleasure experienced while driving. Essentially, it acts as a "bridge" between the occupants of the vehicle and the road they ride on.The term suspension refers to the ability of this bridge to "suspend" a vehicle's frame, body and powertrain above the wheels. Like the Golden Gate Bridge hovering over San Francisco Bay, it separates the two and keeps them apart. To remove this suspension would be like taking a cool dive from the Golden Gate: you might survive the fall, but the impact would leave you sore for weeks.Think of a skateboard. It has direct contact with the road. You feel every brick, crack, crevice and bump. It's almost a visceral experience. As the wheels growl across the pavement, picking up a bump here, a crack there, the vibration travels up your legs and settles in your gut. You could almost admit you were having fun, if you didn't feel like you were gonna toss your tacos at any second. This is what your car would feel like without a suspension system.In the interests of road safety, it is logical to include in periodic roadworthiness tests an inspection of vehicle suspension performance. The results of tests with a prototype machine are presented and a specification proposed for a valid suspension test.Demonstrations organized by the European Shock Absorbers Manufacturers’Association ( EuSAMA) in many countries have drawn attention to the importance of correctly functioning shock absorbers. In the United Kingdom it is anticipate that the Department of the Environment will include a specific shock absorber check in the MOT Test with effect from January 1977.Of the machines currently available for testing shock absorbers without removing them from the vehicle, there is no real consensus of opinion concerning their validity to evaluate suspension safety objectively. But it is felt that possiblemore stringent legislation on European periodic vehicle tests in the future will demand a form of objective testing on equipment that is incapable of erroneous interpretation.Since its formation in 1971 EuSAMA has realized the imnportance of the problem, and initially charged its technical sub-committee with the task of examining and analyzing the various test machines then available. Two basic types of machine were offered at that time for diagnosing faulty shock absorbers. These were:Machines which lift up the wheels on an axle by about 100 mm and then let them drop. The subsequent displacements of the body on each side are recorded and the results compared with preset values for the particular vehicle and the suspension position, front or rear. Such a machine simulates a step input and records the subsequent body movements (see Fig 1).Machines which measure wheel movements induced by the exitation of the suspension through a frequency scan from above resonance frequency to zero, applied by means of a spring-supported platform under the tyre. Results are recorded in the form of wheel displacement against time. While passing through the wheel bounce resonant frequency the maximum amplitude is obtained and this is compared with preset values for the particular vehicle and the suspension position front or rear (see Fig 2).A third machine, introduced later, measures phase shift induced by the excitation of the suspension at a constant frequency and stroke, applied by means of a vibrating platform under the tyre. The phase shift between the moment of excitation and the force-reaction is recorded and the result is compared with preset values for the particular vehicle and suspension position (see Fig 3).These systems have three fundamental drawbacks:A: The actual damping is compared with the original damping the limit being a certain degradation in comparison with the original performance. The original performance, however, can already be marginal.B: The problems of limit setting, namely by whom should the limits be set and what are the criteria they should about? At present there is hardly anyrelation between set limits and acceptable performance in practice.C: The practical problem of various limits for different vehicle types and their suspensions. This requires comprehensive reference manuals that need continuously updating.Despite these fundamental drawbacks, examples of the ? widely used test machines were put through their paces by the Automotive Engineers Laboratory of the University of Ghent, as well as by several EuSAMA members. As expected, the first conclusion is that no test method which does not include dismantling the shock absorbers from the vehicle is able to furnish information concerning the shock absorber alone, and it is in fact the whole of the vehicle suspension system that is tested. This can be considered as a positive aspect of testing, since the whole of the suspension should be in good condition for safety; although the shock absorber is the component most likely to deteriorate with use, other defects such as incorrectly inflated tyres, broken springs or seized ball-joins should if possible be diagnosed.Of the other factors which influenced test results it was found that all machines gave results that were much affected by shock absorber temperature. In the case of the drop type testing machines, defects in shock absorbers caused by high frequency excitation could not be detected. With the frequency scan type of machine, approximately constant force input implies a big difference in results between vehicles with soft or hard suspension, so that changes in springs from normal to heavy duty (which the operator may be incapable of identifying ) can considerable affect the result.Each make of machine had its own characteristics, but as the basic test principles were considered to be unacceptable these details will not be presented here.After due consideration the technical sub-committee advised the General Assembly of EuSAMA that although the existing machines, when correctly operated, could help to diagnose many faulty shock absorbers, a responsible association could not authorize such equipment as the parameters measured were not considered technically representative of any particular aspect ofroadworthiness.Taking brake testing as an example, it was noted that test machines give a direct reading of braking efficiency as a percentage of g without the need to identify vehicle type or to use reference manuals. Similarly, minimum braking performance levels can be set for all automobiles irrespective of model, so that a customer knows immediately if his brakes need attention, Some machines show brake imbalance, but do not indicate which component is faulty.Applying the same principles to vehicle suspension, it should be possible to propose a test which furnishes a direct reading as a value or preferably as a percentage, to indicate whether a suspension is considered satisfactory from the viewpoint of safety. Moreover, this must be achieved objectively, that is to say without need of any identification, interpretation or reference to manuals by the test operator.The technical sub-committee therefore looked for a parameter which could be considered a suitable criterion of safety in relation to vehicle suspension. As stated earlier, there is only one component normally subject to deterioration with use—the shock absorber. So the role of the shock absorbers must first be defined. These have two functions to perform: to damp the movement of the vehicle body on its springs and to control wheel bounce.The permitted movement of a vehicle body on its springs is very much a matter of taste, and it is largely in the control of such movement that a sports shock absorber differs in damping characteristics from a shock absorber aimed at optimum comfort. The movement of a body on its springs does, of course, materially influence roadholding but in reality few ordinary drivers are capable of reaching the limits of the modern car in this respect, so the value of body damping is relatively unimportant for safety measurements. In any case, most drivers of a vehicle with poor body damping will quickly limit their speed and manoeuvres to the vehicle’s handling capacity.Wheel bounce, on the other hand, is a measurable phenomenon and the dangers of vehicles with uncertain wheel contact are well known. Both cornering and braking performance are well known. Both cornering and brakingperformance are limited by tyre anherence to the road; this is dependent on the vertical wheel contact as well as the tyre’s own properties.A parameter which permits the objective measurement of one aspect of roadholding, and therefore of vehicle suspension safety, was thus isolated but it was still necessary to be able to express it in terms that could be readily interpreted.It was proposed, therefore, to measure the minimum remaining vertical contact force between tyre and road under a given excitation at wheel-bounce frequency and to express it as a percentage of the static wheel load. Such a possibility was discussed at a meeting between the technical sub-committee and Dr Verschoore of the University of Ghent. A general concensus of opinion in favour of such a test was reached, though some members expressed doubts concerning the possibility of measuring this parameter in practice, as well as doubts concerning the results Aparamet。