汽车车辆类分动箱的工作分析应用外文文献翻译、中英文翻译、外文翻译
附录
所谓分动箱，就是将发动机的动力进行分配，分别输出给前轴和后轴的装置。从这个角度可以看出，分动箱实际上是四驱车上的一个配件。随着四驱技术的发展，分动箱也一直进行着改变，并逐渐形成了风格迥异的分动箱，匹配在不同诉求的四驱车上，它们的基本原理和功能也都是各不相同的。
最早的四驱技术，是基于提高车辆的通过性开发的，我们把它称作越野四驱。这类车型的鼻祖威利斯吉普，就是二战美军为了加强前线步兵和指挥官作战的机动性开发出来的。它采用的分动箱是最基本的分时四驱分动箱，是一种纯机械的装置。这种结构的分动箱，在挂上4驱模式的时候，前后轴是刚性连接的，可以实现前后动力50∶50的分配，对于提高车辆的通过性非常有利。另外由于它的纯机械结构，可靠性很高，这对于经常在缺少救援的荒野行驶的车型是至关重要的。即使到现在，仍然有大量的硬派越野车采用这种分动箱，就是基于它这个特点。下面我们就来看看这种分动箱的基本结构和原理。
在此类车型的分动箱挡把上，我们会看到2H、4H、N、和4L的切换挡位。当挂2H时，此类车型就是一台后驱车，发动机的动力经过变速箱以后，通过一根传动轴直接连接到后轴上。而分动箱的作用，就是在变速箱上，再引出一根输出端，并通过静音链条，将动力传递到前轴的输出轴。当然，这并不是直接连接的，否则就无法切换4驱和2驱了。事实上，它是通过两组齿轮实现分离和连接的，它的结构和原理类似于变速箱的一轴和二轴。切换时，扳动分动箱的挡把，通过拨叉将动力与前传动轴接通和断开。与现在主流的带同步器的变速箱不同，这个部位的切换是没有同步器的，它需要转速与轮速的完全匹配。这就是这种分动箱的基本原理。
但实际情况并不会这么简单，为了提高通过性能，这类分动箱还会有一个加力挡，也就是挡把上的4L模式。在变速箱上，有一个齿比更大的齿轮，当挂上这个齿轮时，能提供比日常驾驶高很多的主传动比。我们发现，当我们需要挂4L时，必须经过一个N挡，此时变速箱会将动力与每个传动轴分开，而挂上4L时，将接通这个齿比更大的齿轮。这个切换的过程，也是没有同步器的。
知道了这个原理，我们再来看看此类分动箱各个模式的操作特性。熟悉传统越野车的车友都知道，这种分动箱，在2H和4H之间切换时，不需要停车，一般可以在80公里/小时的时速下自由切换。而切换到2L时，则必须停车切换，否则根本挂不进去，这是为什么呢？
无论是2H模式还是4H模式，动力一直是与后轴接通的，后轮的轮速与发动机转速完全匹配。而此时只要车轮没有打滑，前轮与后轮的轮速是一样的，因此在2H与4H之间切换时，发动机转速与前输出轴的转速是匹配的，即使没有同步器，也完全可以进行切换。因此在2H模式和4H模式间切换，完全可以在行车中进行，不需要停车切换。但到了4L模式的转换时，情况就完全不同了。
从4H切换到4L模式，需要先将分动箱切换为N挡，此时发动机动力与每个车轮都断开，发动机转为怠速工况。此时如果挂4L，车轮的轮速与发动机的转速会很难匹配，相当于一台不带同步器的车行驶过程中想挂一挡，这显然是很难的。
这种分动箱前后轴之间是没有差速器的，因此在附着力高的公路上驾驶只能挂2H，4驱模式仅仅是在沙石路面以及OFF-ROAD路段为提高通过性而设计。因此采用这种分动箱的四驱车一般都是硬派越野车，它在OFF-ROAD路段很厉害，但在公路上则表现平平。
早期的分时四驱，是完全靠手动切换的，发展到后来，出现了电动切换的分时四驱，它的基本原理与手动切换的分时四驱是一样的，只不过所有的切换是通过电机来完成罢了。
1.全时四驱分动箱
随着四驱技术的发展，人们已经不能仅仅满足于只能越野的四驱车。在公路上，采用四驱技术的车辆能提供更好的驱动力和操控性能，因此全时四驱诞生了。
硬轴连接的四驱车不能实现公路四驱驾驶的最主要的原因，是它无法在公路上高速转弯。因为在转弯的时候，每个车轮所压过的弧线长度不一样，这就意味着每个车轮的转速都不能一样。事实上，前轮的转速是会高于后轮的，如果刚性地把发动机的动力通过传动轴分配给前后车轮的话，那么前后车轮的转速就必须保持一致，这个矛盾将导致前后车轮在转向的时候发生转向干涉。这在附着力低的沙石路面可以通过轮胎与地面的滑动摩擦解决，而在干燥路面则会产生一个制动力，让车不能前进，这就是我们常说的转向制动。
为了解决这个矛盾，工程师在分动器中加入了一个差速器，这就是我们现在常说的中央差速器。这个差速器是开放式差速器，结构与前后轴的差速器一样，变速箱的输出轴通过行星齿轮组将动力分配给前后轴。根据开放式差速器的原理，它可以调整转速差。这样的结构是不是就算是全时四驱了呢？早期全时四驱的雏形确实是这样的，但我们会发现，这样的四驱系统对于提高通过性来说毫无意义。我们知道，开放式差速器的功能是把发动机动力分配给受阻力小的车轮，如果一台车上使用了三个开放式差速器（前后轴各还有一个差速器）来调节转速差的话，那么如果有一个车轮受阻力最小，动力就会100%地传递给这个车轮。显然这种四驱是毫无意义的。
为了解决这个问题，不同的工程师采用了两种不同的方案。
一种是差动限制器。我们已经知道，开放式差速器会将动力传递给受阻力较小的车轮，那如果我们给这辆车人为施加一个阻力，动力自然就能传递给没有打滑（仍然有抓地力）的车轮了。它的基本结构是一种类似于离合器的装置，只不过它有很多组，我们把它称作多片离合器式差动限制器。在差速器壳体和两个输出轴各有一组钢片，它们相互交错，正常情况下互相之间是分离的。如果此时前轮打滑，它会将与前轴的离合器片压合，从而将动力更多地传递给后轮，后轮打滑的道理是一样的。这种差动限制器的种类有很多，有通过硅油实现的机械式（关于硅油的原理后文会详述），也有通过电子控制离合器开合的电子式。在比较高档的车型上，它的差动限制器不仅解决车轮打滑的问题，还能起到主动分配动力的作用，甚至可以实现让动力从0-100%之间在前后轴自由分配。
另一种则是中央差速锁。它实际上相当于在需要提高通过性的时候，可以将前后轴实现硬轴连接，动力按照50∶50分配给前后轴。它的基本结构是，在前后轴之间装有摩擦钢片，当前轮或者后轮打滑时，机械装置会通过电磁阀的控制将二者咬合实现50∶50的固定动力分配。还有一种全时四驱的分动器结构，那就是著名的奥迪QUA TTRO。它主要是通过蜗杆行星齿轮来实现的，结构很复杂，这里就不再详述了。它这种结构能解决转速差的问题，起到开放式差速器的作用，
同时又能自动将动力分配给受阻力最大的问题，起到差动限制器的作用。它可以实现动力25%—75%之间的自由分配，而所有这些，都是通过它核心的托森差速器来实现的，更为神奇的是，这个托森差速器没有用到任何电磁装置，是纯机械式的。无论多先进的电子设备都有响应滞后的问题，因此与其他厂家的技术相比，纯机械的QUATTRO在响应速度方面是无人能及的。当然它也有弊端—结构复杂、造价高、动力传递损失大是它无法跨越的硬伤。
与全时四驱匹配的还有电子差速制动，主要是用来调整左右车轮的转速差的，相当于前差速锁和后差速锁。与差动限制器相比，它的能量损耗较大，一般不用来实现前后车轮的动力分配。
2.适时四驱的分动箱
在此之后，有些厂家的工程师们发现，并不是所有路况都需要四驱系统的，例如在正常公路巡航驾驶的时候，只通过两轮驱动就完全能满足所有的驾驶需求了。此时如果仍采用全时四驱，既不经济，也没有必要。因此，在多数情况下只是两轮驱动，而在必要的时候自动变为四驱的适时四驱诞生了。
适时四驱也有两种解决方案，一种是以本田CR-V为代表的通过粘性连轴节实现；一种是以上一代的4-MATIC为代表的通过多片离合器实现。它们虽然都能达到正常时两轮驱动，驱动轮打滑时自动接通四驱的效果，但结构和功能还是有区别的。
CR-V为代表的这类适时四驱分动箱结构最为简单，它是基于前横置发动机前轮驱动的技术平台，在两驱方面，与之前的轿车平台完全一样。在此基础上，工程师在变速箱上引出一根通往后轴的输出轴，与后桥差速器之间，采用粘性连轴节连接。在这个连轴节里充满了硅油，它的特点是温度升高以后粘度也会迅速升高。在连轴节的输出端和输入端，都装有一个叶片，就类似于液力变矩器的结构。当正常行驶前轮没有打滑的时候，前后轮之间是没有轮速差的，这个粘性连轴节里的两根轴相互之间也就没有转速差。此时动力是不会传递给后轴的。当前轮打滑的时候，前轮的转速将大于后轮，此时粘性连轴节里的输入端转速会超过输出端，就如同液力变矩器一般，能够将动力传递给后轴。不仅如此，由于转速差能导致硅油升温而变粘稠，从而进一步增加对动力的传递，驱动后轮。通过这个结构我们会发现，它的响应速度是比较慢的，而且动力传递也很有限，很难将50%的动力分配给后轴。但它的结构简单、成本低，对于以城市道路驾驶的SUV来说，基本能满足其需求。
上一代4-MATIC为代表的适时四驱分动箱，结构比粘性连轴节的适时四驱要复杂一些，与前面所说的中央差速锁有些类似，它是通过电磁离合器来实现四驱接通的。它同样是基于两驱平台开发出来的四驱系统，在变速箱的一端通过盆型齿轮引出一根传动轴将动力传递给前轮，之间靠多片离合器连接。它的接通与断开的原理与之前说的中央差速锁的原理类似，这里就不赘述了。它的好处是结构比全时四驱简单，响应速度和动力分配比粘性连轴节要好。
随着结构的四驱技术的进一步发展，现在有些车型已经可以实现动力的自由分配了，很多的官方宣传把这种四驱也称作全时四驱，事实上是不准确的。与具备中央差速锁的真正全时四驱相比，这种靠多片离合器实现动力分配的所谓全时四驱，最多只能将动力的50%分配给从动轮，而且在转弯时的动力分配等方面，都无法达到真正全时四驱的水平。从本质上说，这类四驱仍然只能称作适时四驱，例如大众的4-Motion。3.超选四驱分动箱
这个称呼是三菱的，一直以来也被看做是三菱的看家技术。
从分动箱的挡把看，它更像是传统的分时四驱系统，所不同的是，它是具备中央差速器的。当挂上4H的时候，不仅能在沙石路面上高速行驶，也能在普通公路上实现公路四驱的功能。而它提供的4HLC和4LLC选项，则是锁上了中央差速锁的四驱模式，在这个时候，它与分时四驱的4H和4L的功能是一样的。
之所以三菱称之为超选，实际上是因为它比所有的四驱系统可选择的范围都要多。一般的全时四驱车，只能选择四驱行驶，在不需要四驱的时候，这样的方式显然不经济；而适时四驱虽然可以实现两驱，但在四驱的时候无法达到真正的全时四驱的性能；分时四驱就不用说了，它完全不能实现公路四驱驾驶。而所有这些，超选四驱都能选择—想经济性好，就挂上2H，想公路全时四驱就挂上4H，想达到与传统分时四驱一样的通过性，就挂上4HLC或者4LLC。
The so-called transfer case, is the power of the engine for the distribution, output to front a xle and rear axle respectively of the device. From this point of view can see, transfer case is ac tually the raider buggies a accessories. Along with the raider buggies technology development, th
e transfer case also has been the change, and gradually form the style different transfer case, ma tching the raider is in different appeal, their basic principle and function are also different.
The first raider technology, is based on the improve vehicle through sexual deve lopment, we called it the cross-country raider buggies. This kind of car is the ancest or of the second world war, American troops Willis jeep in order to strengthen the front line infantry and commander of the development of mobility out of combat. It used Transfer case is the most basic points raider Transfer case, is a pure mechani cal device.The structure of the Transfer case, hang up the 4 flooding patterns, rear a xle is before the rigid connection, may realize the power 50: the before and after 5 0 distribution, to improve the vehicles through sexual very favorable. Plus, because i t purely mechanical structure, high reliability, this to often lack the wilderness in res cue vehicles driving is very important. Even now, there are still a lot of hard sent b y theTransfer case suv, is based on the characteristics of it. Let's take a look at this Transfer case basic principle and structure.
In this kind of car Transfer case on the block, we will see 2H,4H,N and 4L s witching gears. When hang 2H, such models is a whip, the power of the engine dri ving after gearbox, through a shaft after root connected directly to the rear axle. An d Transfer case role, which is in the gearbox, and then lead to an output terminal, and through the mute chain, will power transfer to the front axle output shaft. Of c ourse, this is not to direct connection, it will not switch 4 flooding and 2 flooding. In fact, it is through the two groups of gear separated and connection of the structu re and principle, it is similar to the one axis, and two transmission shaft. When swit ching Transfer case throw of the block, through the fork will power and transmissio n through and disconnect before. And now the mainstream with synchronizer gearbo x, the part of the different switching is no synchronizer, it needs the wheel speed a nd the match. This is the Transfer case basic principle.
But the truth is not so simple, in order to improve the performance of this kind of Transfer case through, there will still be one block, also is the strength of the block on 4L model. In t he gearbox, more than the gear tooth, when hung up the gear, can provide a much higher than daily driving the main transmission. We found that when we need to hang 4L, must go through a N block, at this time will power and each transmission shaft separated, and hang up 4L, will be through to this tooth more than the gear. The switch of the process, is also no synchronizer.
Know the principle, we take a look at this Transfer case each mode of operation characteristics. Familiar with traditional suvs, having know this Transfer case, in 2H and 4H, we do not need to switch between parking, can generally in the 80 km/hour per hour free switch. And switch to 2L, it must stop switch, or fundamental hang in, is this why?
Whether 2H mode or 4H mode, the power is always connected with rear-axle, the rear whe
els wheel and engine speed completely match. But at this time as long as no sliding, front whee l and rear wheel speed is same, so in 2H and 4H switch between, engine speed and output shaf t speed is before the match, even without synchronizer, also can switch. So in 2H mode and 4H mode, can switch between the onboard, need not stop switch. But in the 4L mode switch, it w as completely different. From 4H switch to 4L model, need to add Transfer case switch for N block, this time of engine power and each wheel are disconnected, engine to idling process. I f this time the wheels of L, hang 4 wheel and the speed of the engine can be hard to match, e quivalent to a without synchronizer driving process want to hang a block, this is clearly a very difficult.
This Transfer case between front axle is not between the differential, therefore i n the high adhesion of the ROAD can only hang 2H, 4 flooding mode is only in t he gravel ROAD and OFF ROAD sections to improve-through sexual and design. So the method of this Transfer case buggies are generally hard-line rovers, it in the O FF-ROAD sections it bad, but in the highway is average performance.
The early time, is totally by manual raider switch, later, there was electric switc h points raider buggies, it the basic principles and manual switching points raider is same, but all of the switch is through the motor to complete it.
1.Transfer case full-time raider buggies
With the development of the technology of raider buggies, people are not satisfi ed with just four drove cross-country only. In the highway, the raider buggies techno logy vehicles can offer a better driving force and control performance, so full-time r aider was born.
Hard shaft link of raider buggies can't achieve highway raider driving the main reason, is it not in freeway turn. Because in when turning, each wheel crushes the a rc length different, this means that each of the wheel speed are not the same. In fac t, the speed of the front wheel is will be higher than the rear wheels, if the rigid t o the power of the engine through the drive shaft before and after assigned to the wheel, then the before and after the wheel speed must be consistent, the contradictio n between before and after the steering wheel will lead to occur to interfere. The ad hesion of sand of pavement in low by the sliding friction tires and the ground, and in dry pavement solution will produce a braking, let the car won't go forward, this i s we often say to brake.
In order to resolve the contradiction, the engineer in thansfer joined the a differ ential, this is we are now often say the central differential. The differential is open differentials, structure and the differential between front axle, as well as the output s haft transmission through planetary gear set will power distribution to rear axle befor e. According to the principle of differential open mode, it can adjust the speed diffe
rence. This structure is even full-time raider? The prototype of the early full-time rai der is really such, but we will find, the raider buggies to improve the system throug h sexual makes no sense. We know, open mode is the function of differential the en gine power distribution to the small resistance wheels, if a car use of three open dif ferential (between front axle and a differential) each to adjust the speed difference o f words, so if there is a wheel has the least resistance, by motivation to transfer to the wheels by 100%. Obviously this raider is pointless.
In order to solve this problem, different engineer USES two different project.
One is the differential limit. We already know, open mode will be passed to the power differential resistance smaller wheels, by that if we give the car a resistance on human nature, the power can be passed to the no sliding (there are still grip th e wheels of). Its basic structure is a kind of similar to the device, but it clutch man y groups, we called it the multi-gear clutch type differential limit device. In the diff erential shell and two output shaft each have a set of pieces of steel, their mutual c risscross, normally between each other is separated. If the front wheels skid, it will front axle and the pressure and the clutch disc, which will power transfer to the rea r wheels more, rear wheel slippage, the truth is the same. This is the type of differ ential limit has a lot of, have through the silicone oil of the realization of the mech anical (about the principle of silicone oil after described the) and through the electro nic control of electronic electrical switching of the clutch. In the more upscale cars, it is not only the differential limit solution to the wheel slippage problem, still can have the initiative of the power distribution function, can even realize the power fr om 0 to 100% in the first free distribution between rear axles.
Another is the central differential lock. It actually is equivalent to need to impr ove through the sex, can be hard to realize between front axle shaft link, power, ac cording to 50 50 assigned to rear axle before. Its basic structure is in between, bet ween front axle with friction, the current round of steel or rear wheels skid, mechan ical device will through the electromagnetic valve control of both a bite to realize t he fixed, 50 50 power distribution. There is a full-time raider buggies, that is the th ansfer structure of the famous audi QUATTRO. It is mainly through the worm plane tary gear to achieve, structure is complex, here no longer expatiatory.
This structure can solve the problem of poor speed, plays the role of open diffe rential, at the same time can automatically will power distribution to the resistance o f the biggest problems that have the function of the differential limit. It can achieve 25%-75% of power between free distribution, and all this is through the core of it, to realize the differential's, more magical is, the "spider's without the use of any el
ectromagnetic device that is pure mechanical. No matter how advanced electronic eq uipment are lags in response problem so and other manufacturers of technical, comp ared the purely mechanical QUATTRO in velocity response is no one can and. Of c ourse it has drawbacks-structure is complex, cost is high, power transmission loss is it could not cross the shortcomings.
And full-time raider matching and electronic differential braking, is mainly used to adjust or so the wheel speed difference, before the lock and differential equivale nt after differential lock. And the differential limit, compared the energy loss is bigg er, generally do not to realize the wheels of before and after power distribution.
2.The raider Transfer case timely
After that, some manufacturer's engineers found that not all need raider system of the road, for example in the normal cruising highway driving, only through the t wo wheel drive was completely can meet all driving demand. If this time still use a full-time raider buggies, neither economy, also don't have to. Therefore, in most cas es only two wheel drive, and when necessary to be automatic into the raider buggie s timely raider was born.
Timely raider buggies also have two solutions, one with Honda CR-V, as a repr esentative of the cohesive shaft quarter even through implementation; A is above gen eration of 4 MATIC-as a representative of the through the multi-gear clutch realized. Although they can achieve normal when two wheel drive, the drive wheels skid aut omatically through the effect of raider buggies, but yet there are differences between the structure and function.
CR-V as a representative of this kind of timely raider Transfer case structure m ost simple, it is based on the horizontal buy before the engine front wheel drive tec hnology platform, in two aspects, and flooding the car platform is exactly the same as before. On this basis, the engineer in the gearbox brings the root to rear axle out put shaft, and driving axle differential between, use the cohesive shaft quarter even connection. Even in the shaft section is filled with silicone oil, it is characteristic of temperature rise will also rise after viscosity. Even the axis of the festival in outpu t and input, are equipped with a blade, similar to the hydraulic torque converter stru cture. When moving the nose wheel is not skid, there is no round between the cont rol speed difference, the cohesive shaft in the quarter even two shaft between each other is no speed difference. At this time is not passed to power the rear axle. The current round of sliding, the speed of the front wheel will be greater than the rear wheels, even at this time of day cohesive shaft input speed will more than the out put, as hydraulic torque converter general, able to power transfer to rear axle. Not o
nly that, because the rotation speed difference can cause heating up and become visc ous silicon oil, so as to further increase the power of transmission, rear wheel drive.
Through this structure, we will find that the response speed, it is more slowly, and power transfer is limited, and it is difficult to will be 50% of power distributi on to rear axle. But its simple structure, low cost, for city road driving to the SUV, it can meet the basic needs.
A generation 4 MATIC-as a representative of the timely Transfer case raider bu ggies, structure than even shaft section of the sticky timely raider is more complicat ed, and the above the central differential lock some similar, it is through the electro magnetic clutch to realize the raider buggies. It is also based on two flooding platfo rm is developed, the raider buggies system in one end of the transmission in the ba sin type gear shaft brings the root will power transfer to front wheel, by connection between multi-gear clutch. It's connected to the broken and principle and said befor e the central differential lock principle similar, there is no redundancy. Its advantage is than full-time raider simple structure, response speed and power distribution cohe sive shaft is better than even section.
Along with the structure of the raider buggies the further development of techn ology, and now some of the vehicles already made the power of the free distributio n, a lot of official propaganda the raider buggies also known as full-time raider bug gies, in fact is not accurate. And is equipped with central differential locks, compare d to the real full-time raider buggies on multi-gear clutch realize power distribution of so-called full-time raider buggies, only 50% of the power distribution, and give t he driven pulley in turning power distribution, cannot reach the level of the raider b uggies full-time real. In essence, this kind of raider buggies still can only be called
a timely, for example the public want unless 4-amount.
3.Super choose Transfer case raider buggies
This call is the mitsubishi, long can also be seen as mitsubishi special technolo gy.
From the Transfer case block to see, it is more like traditional timeshare raider system, which differs is, it is equipped with central differential. When hung up 4H, not only in ShaShiLu face high-speed, also can be in ordinary highway to realize t he function of the raider buggies highway. And it provides four HLC and 4LLC opt ions, is locked the central differential lock mode of raider buggies, at this time, it a nd points of raider buggies 4H and 4L function is the same.
Mitsubishi is called super choose, in fact because than all the raider buggies sy stem can the scope of the choice. The general full-time buggies, can only choose rai
der is traveling in don't need raider buggies, this way clearly not economy; And tim ely raider although can realize two flooding, but in the raider can not reach the real full-time raider performance; Raider points need not say, it completely unable to re alize highway raider buggies to drive. And all these, super choose raider buggies ca n choose-want to economical, he hung up 2H, want to road full-time raider buggies will hang up 4H, want to achieve and traditional points of the same sex, the raider buggies will hang up 4HLC or 4LLC.
汽车专业毕业设计外文翻译
On the vehicle sideslip angle estimation through neural networks: Numerical and experimental results. S. Melzi,E. Sabbioni Mechanical Systems and Signal Processing 25 (2011)：14~28 电脑估计车辆侧滑角的数值和实验结果 S.梅尔兹,E.赛博毕宁 机械系统和信号处理2011年第25期：14~28
摘要 将稳定控制系统应用于差动制动内/外轮胎是现在对客车车辆的标准（电子稳定系统ESP、直接偏航力矩控制DYC）。这些系统假设将两个偏航率(通常是衡量板)和侧滑角作为控制变量。不幸的是后者的具体数值只有通过非常昂贵却不适合用于普通车辆的设备才可以实现直接被测量,因此只能估计其数值。几个州的观察家最终将适应参数的参考车辆模型作为开发的目的。然而侧滑角的估计还是一个悬而未决的问题。为了避免有关参考模型参数识别/适应的问题,本文提出了分层神经网络方法估算侧滑角。横向加速度、偏航角速率、速度和引导角,都可以作为普通传感器的输入值。人脑中的神经网络的设计和定义的策略构成训练集通过数值模拟与七分布式光纤传感器的车辆模型都已经获得了。在各种路面上神经网络性能和稳定已经通过处理实验数据获得和相应的车辆和提到几个处理演习(一步引导、电源、双车道变化等)得以证实。结果通常显示估计和测量的侧滑角之间有良好的一致性。 1 介绍 稳定控制系统可以防止车辆的旋转和漂移。实际上，在轮胎和道路之间的物理极限的附着力下驾驶汽车是一个极其困难的任务。通常大部分司机不能处理这种情况和失去控制的车辆。最近,为了提高车辆安全，稳定控制系统(ESP[1,2]; DYC[3,4])介绍了通过将差动制动/驱动扭矩应用到内/外轮胎来试图控制偏航力矩的方法。 横摆力矩控制系统（DYC）是基于偏航角速率反馈进行控制的。在这种情况下,控制系统使车辆处于由司机转向输入和车辆速度控制的期望的偏航率[3,4]。然而为了确保稳定，防止特别是在低摩擦路面上的车辆侧滑角变得太大是必要的[1,2]。事实上由于非线性回旋力和轮胎滑移角之间的关系，转向角的变化几乎不改变偏航力矩。因此两个偏航率和侧滑角的实现需要一个有效的稳定控制系统[1,2]。不幸的是,能直接测量的侧滑角只能用特殊设备(光学传感器或GPS惯性传感器的组合)，现在这种设备非常昂贵,不适合在普通汽车上实现。因此, 必须在实时测量的基础上进行侧滑角估计，具体是测量横向/纵向加速度、角速度、引导角度和车轮角速度来估计车辆速度。 在主要是基于状态观测器/卡尔曼滤波器(5、6)的文学资料里, 提出了几个侧滑角估计策略。因为国家观察员都基于一个参考车辆模型,他们只有准确已知模型参数的情况下，才可以提供一个令人满意的估计。根据这种观点,轮胎特性尤其关键取决于附着条件、温度、磨损等特点。 轮胎转弯刚度的提出就是为了克服这些困难,适应观察员能够提供一个同步估计的侧滑角和附着条件[7,8]。这种方法的弊端是一个更复杂的布局的估计量导致需要很高的计算工作量。 另一种方法可由代表神经网络由于其承受能力模型非线性系统，这样不需要一个参
机械设计设计外文文献翻译、中英文翻译、外文翻译
机械设计 摘要：机器是由机械装置和其它组件组成的。它是一种用来转换或传递能量的装置，例如：发动机、涡轮机、车辆、起重机、印刷机、洗衣机、照相机和摄影机等。许多原则和设计方法不但适用于机器的设计，也适用于非机器的设计。术语中的“机械装置设计”的含义要比“机械设计”的含义更为广泛一些，机械装置设计包括机械设计。在分析运动及设计结构时，要把产品外型以及以后的保养也要考虑在机械设计中。在机械工程领域中，以及其它工程领域中，所有这些都需要机械设备，比如：开关、凸轮、阀门、船舶以及搅拌机等。 关键词：设计流程设计规则机械设计 设计流程 设计开始之前就要想到机器的实际性，现存的机器需要在耐用性、效率、重量、速度，或者成本上得到改善。新的机器必需具有以前机器所能执行的功能。 在设计的初始阶段，应该允许设计人员充分发挥创造性，不要受到任何约束。即使产生了许多不切实际的想法，也会在设计的早期，即在绘制图纸之前被改正掉。只有这样，才不致于阻断创新的思路。通常,还要提出几套设计方案，然后加以比较。很有可能在这个计划最后决定中,使用了某些不在计划之内的一些设想。 一般的当外型特点和组件部分的尺寸特点分析得透彻时，就可以全面的设计和分析。接着还要客观的分析机器性能的优越性，以及它的安全、重量、耐用性，并且竞争力的成本也要考虑在分析结果之内。每一个至关重要的部分要优化它的比例和尺寸，同时也要保持与其它组成部分相协调。 也要选择原材料和处理原材料的方法。通过力学原理来分析和实现这些重要的特性，如那些静态反应的能量和摩擦力的最佳利用，像动力惯性、加速动力和能量；包括弹性材料的强度、应力和刚度等材料的物理特性，以及流体润滑和驱动器的流体力学。设计的过程是重复和合作的过程，无论是正式或非正式的进行，对设计者来说每个阶段都很重要。 最后，以图样为设计的标准，并建立将来的模型。如果它的测试是符合事先要
旅游服务贸易外文翻译文献
旅游服务贸易外文翻译文献(文档含英文原文和中文翻译)
旅游服务贸易的国际竞争力：罗马尼亚的案例 引言 旅游业是唯一的可以为任何发展水平的国家提供贸易机会的服务活动。然而，它也是一个很大程度因为国家的能力和在全球经济中的表现而又有明确的利益分配不均行业，而这又需要提高自己的竞争力。 自20世纪90年代初，罗马尼亚旅游业经历了出口量，生长速率和结构的重大变化。这些不同的波动都影响了罗马尼亚在国际旅游市场上相对的竞争地位并引起了其旅游贸易平衡的变化。同时，新的和更多的错杂的欧式建筑，引起了罗马尼亚的区域旅游竞争力的显著变化。 在此背景下，本文试图提出一个框架，以竞争力和旅游贸易表现之间的关系为重点，来评估罗马尼亚的旅游服务贸易的国际竞争力。 一、国际竞争力视角：国际竞争力之与国际旅游业的相关性 国际竞争力的概念，尽管有争议，难以捉摸，但现在已经得到认可，并继续吸引世界各地的学者和决策者的关注。 到目前为止，为提高国际竞争力已采取措施，都被认为是在经济层面进行的(加瑞利，2003)通常是指一个国家生产的商品和服务，以满足国际市场的考验，并同时保持和增加公民的收入的能力(欧洲委员会，2007)。 由于竞争力最终取决于一国企业在国内和国际的市场成功，所以对竞争力的注意力都集中在企业层面的竞争力上(波特，1990)，对于此的普遍理解是指“……该公司保持，并更好的是，扩大其全球市场份额，增加和扩大利润的能力” (克拉克和盖，1998, 经济合作与发展组织，1993)。 因此，虽然广泛流传但是国际竞争力作为与国家经济和其国际贸易相关
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外文文献翻译：汽车的发展
The development of automobile As the world energy crisis and the war and the energy consumption of oil -- and are full of energy in one day someday it will disappear without a trace. Oil is not inresources. So in oil consumption must be clean before finding a replacement. With the development of science and technology the progress of the society people invented the electric car. Electric cars will become the most ideal of transportation. In the development of world each aspect is fruitful especially with the automobile electronic technology and computer and rapid development of the information age. The electronic control technology in the car on a wide range of applications the application of the electronic device cars and electronic technology not only to improve and enhance the quality and the traditional automobile electrical performance but also improve the automobile fuel economy performance reliability and emission spurification. Widely used in automobile electronic products not only reduces the cost and reduce the complexity of the maintenance. From the fuel injection engine ignition devices air control and emission control and fault diagnosis to the body auxiliary devices are generally used in electronic control technology auto development mainly electromechanical integration. Widely used in automotive electronic control ignition system mainly electronic control fuel injection system electronic control ignition system electronic control automatic transmission electronic control ABS/ASR control system electronic control suspension system electronic control power steering system vehicle dynamic control system the airbag systems active belt system electronic control system and the automatic air-conditioning and GPS navigation system etc. With the system response the use function of quick car high reliability guarantees of engine power and reduce fuel consumption and emission regulations meet standards. The car is essential to modern traffic tools. And electric cars bring us infinite joy will give us the physical and mental relaxation. Take for example automatic transmission in road can not on the clutch can achieve automatic shift and engine flameout not so effective improve the driving convenience lighten the fatigue strength. Automatic transmission consists mainly of hydraulic torque converter gear transmission pump hydraulic control system electronic control system and oil cooling system etc. The electronic control of suspension is mainly used to cushion the impact of the body and the road to reduce vibration that car getting smooth-going and stability. When the vehicle in the car when the road uneven road can according to automatically adjust the height. When the car ratio of height low set to gas or oil cylinder filling or oil. If is opposite gas or diarrhea. To ensure and improve the level of driving cars driving stability. Variable force power steering system can significantly change the driver for the work efficiency and the state so widely used in electric cars. VDC to vehicle performance has important function it can according to the need of active braking to change the wheels of the car car motions of state and optimum control performance and increased automobile adhesion controlling and stability. Besides these appear beyond 4WS 4WD electric cars can greatly improve the performance of the value and ascending simultaneously. ABS braking distance is reduced and can keep turning skills effectively improve the stability of the directions simultaneously reduce tyre wear. The airbag appear in large programs protected the driver and passengers safety and greatly reduce automobile in collision of drivers and passengers in the buffer to protect the safety of life. Intelligent electronic technology in the bus to promote safe driving and that the other functions. The realization of automatic driving through various sensors. Except some smart cars equipped with multiple outside sensors can fully perception of information and traffic facilities
外文翻译中文
运作整合 供应链协作的首要问题是提高运作整合的程度。供应链协作课达到的好处，直接关系到捕捉效率之间的职能的企业，以及全国的企业，构成了国内或国际供应链。本章重点阐述的挑战，一体化管理，由研究为什么一体化创造价值，并通过详列的挑战，双方的企业集成和供应链整合。必不可少的供应链流程是确定的。注意的是，然后向信息技术提供，以方便集成化供应链规划。本章最后审查了定价。在最后的分析，定价的做法和政府是至关重要的供应链的连续性。 为什么整合创造价值 基本的优点与挑战的综合管理介绍了在第1章。进一步解释整合管理的重要性，有用的指出客户都至少有三个角度的价值。 传统的角度来看，价值是经济价值。第二个价值的角度来看，是市场价值。 实现双方经济和市场价值是很重要的客户。然而，越来越多的企业认识到商业上的成功也取决于第三个角度来看，价值，被称为关联性。 物流一体化目标 为实现物流一体化的供应链背景下，6个业务目标必须同时取得：（ 1 ）响应，（ 2 ）差额减少，（ 3 ）库存减少，（ 4 ）托运巩固，（ 5 ）质量，（ 6 ）生命周期支持。的相对重要性，每个直接关系到公司的物流战略。 响应 一公司的工作能力，以满足客户的要求，及时被称为反应。作为一再指出，信息技术是促进反应为基础的战略，允许业务的承诺被推迟到最后可能时间，其次是加速投放。实施对应策略服务，以减少库存承诺或部署在预期客户的需求。响应服务转向业务重点从预测未来的需求，以容纳顾客对快速订单到出货的基础上。理想的情况是，在一个负责任的系统中，库存是没有部署，直到客户承诺。支持这样的承诺，公司必须有物流的属性，库存的可用性和及时交付，一旦客户订单收到。 差异减少 所有经营领域的物流系统很容易受到差额。方差结果从未能履行任何预期的层面后勤业务不如预期。举例来说，毫不拖延地在客户订单处理，意想不到的干扰，以便选择，抵港货物损坏，在客户的位置，和/或未能提供在适当的位置上的时间，所有创造无计划的差异，在订单到交货周期。一个共同的解决办法，以保障对不利的差异是使用库存安全库存，以缓冲行动。这亦是共同使用的首选运输，以克服意想不到的差异延误交货计划。这种做法，鉴于其相关的成本高，可以尽量减少使用资讯科技，以维持积极的物流控制。向程度的差异是最小化，物流的生产力将提高。因此，差异减少，消除系统中断，是一个基本的目标，综合物流管理。 库存减少 要达到的目标，库存减少，一个综合物流系统必须控制资产的承诺，并把速度。资产的承诺，是财政的价值部署清单。把速度，反映了利率，这是充实库存随着时间的推移。高转率，再加上预期的库存供货，平均资产用于库存正在迅速而有效利用，这就是整体资产承诺支持一个综合运作减至最低。 库存能够而且确实方便可取的好处这是很重要的要请记住。库存是至关重要的实现规模经济，在制造业和采购。目的是要减少和管理存货，以尽可能最低的水平，同时实现整体供应链绩效的目标。
外文翻译---汽车车身总布置的方法
附录 Modern car’s design always stresses people-oriented, so safety, comfort, Environmental protection and energy saving have been the design theme And target in car design. Ergonomics layout design is not only relate to the effective use of internal space and improve car’s comfort and safety Performance, but it will also impact internal and external modeling results, and further affects the vehicle's overall performance and marketability.Soergonomics’application and research during car design and development process occupy an important position.After more than 50 years of construction and development, China’s Automobile industry has become the leading power of automobile production and consumption in the world. In particular, with the rise and rapid de velopment of independent brand’s vehicles, we pay more attention To the development processes and the technical requirements of hard Points’ layout. Through the three typical processes such as modern vehicle developing Process, body development process and using ergonomic to progress Inner auto-body layout, describe ergonomic layoationship between design, Aunt design in which stage of the process of vehicle development, the red The importance of working steps. The automobile body total arrangement is the automobile design most initial is also the most essential step, is other design stage premise and the foundation, to a great extent is deciding the body design success or failure. Picks generally in the actual design process With by forward and reverse two design method (1) to design (from inside to outside law) to design method namely "humanist", is coming based on the human body arrangement tool to define the pilot and the crew member gradually rides the space and the vehicle comes to pay tribute each article the arrangement, take satisfies the human body to ride with the driving comfortableness as the premise, said simply is determined first satisfies the human body to ride under the comfortable premise, carries on the indoor arrangement first, then carries on the complete bikes external styling design again. The concrete method and the step are as follows: ①Determine 5% and 95% manikin H position and the chair by the SAE recommendation's enjoyable line or the region law adjustment traveling schedule, seat
汽车保险中英文对照外文翻译文献
汽车保险中英文对照外文翻译文献(文档含英文原文和中文翻译)
汽车保险 汽车保险是在事故后保证自己的财产安全合同。尽管联邦法律没有强制要求，但是在大多数州（新罕布什和威斯康星州除外）都要求必须购买汽车保险；在各个州都有最低的保险要求。在鼻腔只购买汽车保险的两个州，如果没有足够的证据表明车主财力满足财务责任法的要求，那么他就必须买一份汽车保险。就算没有法律规定，买一份合适的汽车保险对司机避免惹上官和承担过多维修费用来说都是非常实用的。 依据美国保险咨询中心的资料显示，一份基本的保险单应由6个险种组成。这其中有些是有州法律规定，有些是可以选择的，具体如下： 1.身体伤害责任险 2.财产损失责任险 3.医疗险或个人伤害保护险 4.车辆碰撞险 5.综合损失险 6.无保险驾驶人或保额不足驾驶人险 责任保险 责任险的投保险额一般用三个数字表示。不如，你的保险经纪人说你的保险单责任限额是20/40/10，这就代表每个人的人身伤害责任险赔偿限额是2万美元，每起事故的热身上海责任险赔偿限额是4万美元，每起事故的财产损失责任险的赔偿限额是1万美元。 人身伤害和财产损失责任险是大多数汽车保险单的基础。要求汽车保险的每个州都强令必须投保财产损失责任险，佛罗里达是唯一要求汽车保险但不要求投保人身伤害责任险的州。如果由于你的过错造成了事故，你的责任险会承担人身伤害、财产损失和法律规定的其他费用。人身伤害责任险将赔偿医疗费和误工工资；财产损失责任险将支付车辆的维修及零件更换费用。财产损失责任险通常承担对其他车辆的维修费用，但是也可以对你的车撞坏的灯杆、护栏、建筑物等其他物品的损坏进行赔偿。另一方当事人也可以决定起诉你赔偿精神损失。
服务贸易自由化机制外文文献翻译2014年译文4000字
文献出处：Barattieri A. The mechanism of service trade liberalization[J]. Journal of International Economics, 2014, 92(1): 1-13. （声明：本译文归百度文库所有，完整译文请到百度文库。） 原文 The mechanism of service trade liberalization Barattieri A Abstract In this paper, Service trade liberalization is the key areas of the United States to promote the TPP negotiations, the United States in the negotiations are pushing mechanism of a high standard of service trade liberalization. In this paper the progress of the TPP negotiations and services trade issues important position, on the basis of the acceptance, architecture design, focus on services, regulatory consistency four aspects in the TPP uncovers the "high standards" service trade liberalization mechanism establishment. American "high standards" service trade liberalization mechanism is tailored to the interests of the United States, actually services in the service of the United States. These mechanisms are through to strengthen and promote the TPP platform, forming reversed transmission to other countries. Key words: the TPP; The United States; Service trade liberalization; High standards; Mechanism design America is the first largest exporter global trade in services, and for many years, continues to service trade surplus. Competitive advantage based on service industry and service industry The importance of promoting American exports, jobs and economic growth, the United States in the multilateral, bilateral and regional multiple layers jointly promoting service trade liberalization. In the Uruguay round negotiations, the United States has overcome many obstacles, for the first time to include the Service Trade in multilateral negotiations, contributed to the general Agreement on Trade in services (the Genre - al Agreement on Trade and Service,
汽车变速器设计外文翻译
汽车变速器设计 ----------外文翻译 我们知道，汽车发动机在一定的转速下能够达到最好的状态，此时发出的功率比较大，燃油经济性也比较好。因此，我们希望发动机总是在最好的状态下工作。但是，汽车在使用的时候需要有不同的速度，这样就产生了矛盾。这个矛盾要通过变速器来解决。 汽车变速器的作用用一句话概括，就叫做变速变扭，即增速减扭或减速增扭。为什么减速可以增扭，而增速又要减扭呢？设发动机输出的功率不变，功率可以表示为 N = w T，其中w是转动的角速度，T是扭距。当N固定的时候，w与T是成反比的。所以增速必减扭，减速必增扭。汽车变速器齿轮传动就根据变速变扭的原理，分成各个档位对应不同的传动比，以适应不同的运行状况。 一般的手动变速器内设置输入轴、中间轴和输出轴，又称三轴式，另外还有倒档轴。三轴式是变速器的主体结构，输入轴的转速也就是发动机的转速，输出轴转速则是中间轴与输出轴之间不同齿轮啮合所产生的转速。不同的齿轮啮合就有不同的传动比，也就有了不同的转速。例如郑州日产ZN6481W2G型SUV车手动变速器，它的传动比分别是：1档3.704:１；2档2.202:1；3档1.414:1；4档1:1；5档（超速档）0.802:1。 当汽车启动司机选择1档时，拨叉将1/2档同步器向后接合1档齿轮并将它锁定输出轴上，动力经输入轴、中间轴和输出轴上的1档齿轮，1档齿轮带动输出轴，输出轴将动力传递到传动轴上（红色箭头）。典型1档变速齿轮传动比是3:1,也就是说输入轴转3圈，输出轴转1圈。 当汽车增速司机选择2档时，拨叉将1/2档同步器与1档分离后接合2档齿轮并锁定输出轴上，动力传递路线相似，所不同的是输出轴上的1档齿轮换成2档齿轮带动输出轴。典型2档变速齿轮传动比是2.2:1，输入轴转2.2圈，输出轴转1圈，比1档转速增加，扭矩降低。
外文翻译中文版(完整版)
毕业论文外文文献翻译 毕业设计（论文）题目关于企业内部环境绩效审计的研究翻译题目最高审计机关的环境审计活动 学院会计学院 专业会计学 姓名张军芳 班级09020615 学号09027927 指导教师何瑞雄
最高审计机关的环境审计活动 1最高审计机关越来越多的活跃在环境审计领域。特别是1993-1996年期间，工作组已检测到环境审计活动坚定的数量增长。首先，越来越多的最高审计机关已经活跃在这个领域。其次是积极的最高审计机关，甚至变得更加活跃：他们分配较大部分的审计资源给这类工作，同时出版更多环保审计报告。表1显示了平均数字。然而，这里是机构间差异较大。例如，环境报告的数量变化，每个审计机关从1到36份报告不等。 1996-1999年期间，结果是不那么容易诠释。第一，活跃在环境审计领域的最高审计机关数量并没有太大变化。“活性基团”的组成没有保持相同的：一些最高审计机关进入，而其他最高审计机关离开了团队。环境审计花费的时间量略有增加。二，但是，审计报告数量略有下降，1996年和1999年之间。这些数字可能反映了从量到质的转变。这个信号解释了在过去三年从规律性审计到绩效审计的转变（1994-1996年，20％的规律性审计和44％绩效审计;1997-1999：16％规律性审计和绩效审计54％）。在一般情况下，绩效审计需要更多的资源。我们必须认识到审计的范围可能急剧变化。在将来，再将来开发一些其他方式去测算人们工作量而不是计算通过花费的时间和发表的报告会是很有趣的。 在2000年，有62个响应了最高审计机关并向工作组提供了更详细的关于他们自1997年以来公布的工作信息。在1997-1999年，这62个最高审计机关公布的560个环境审计报告。当然，这些报告反映了一个庞大的身躯，可用于其他机构的经验。环境审计报告的参考书目可在网站上的最高审计机关国际组织的工作组看到。这里这个信息是用来给最高审计机关的审计工作的内容更多一些洞察。 自1997年以来，少数环境审计是规律性审计（560篇报告中有87篇，占16％）。大多数审计绩效审计（560篇报告中有304篇，占54％），或组合的规律性和绩效审计（560篇报告中有169篇，占30％）。如前文所述，绩效审计是一个广泛的概念。在实践中，绩效审计往往集中于环保计划的实施（560篇报告中有264篇，占47％），符合国家环保法律，法规的，由政府部门，部委和/或其他机构的任务给访问（560篇报告中有212篇，占38％）。此外，审计经常被列入政府的环境管理系统（560篇报告中有156篇，占28％）。下面的元素得到了关注审计报告：影响或影响现有的国家环境计划非环保项目对环境的影响;环境政策;由政府遵守国际义务和承诺的10％至20％。许多绩效审计包括以上提到的要素之一。 1本文译自：S. Van Leeuwen.(2004).’’Developments in Environmental Auditing by Supreme Audit Institutions’’ Environmental Management Vol. 33, No. 2, pp. 163–1721
服务贸易外文翻译
关于杭州中心地区服务业竞争力及其发展 战略的评价（节选） 郑建壮，中国浙江省浙江大学城市学院 江海霞，中国浙江省浙江工业大学 摘要：服务行业的竞争力是直接反映在区服务业的发展水平和潜在能力之中的。本文研究了杭州服务行业的发展现状，从中心区的角度构建了一个服务行业的评价指标体系，并分析了杭州每个中心城区服务业的可持续发展的优势和劣势。最后，文章给杭州的服务行业竞争力的提高提出了战略建议。 关键词：中心地区，服务业，竞争力 1. 引言 20世纪80年代以来，全球经济已呈现从“工业经济”转向于“服务经济”的变化趋势。服务业已成为全球经济好转的一个关键的引擎（2005年李和王），它在改善国家经济、增加就业率、调整产业结构和提高生活水平等方面的重要作用是显而易见的。一般来说一个地区的服务行业发展主要集中于中部地区，而不是郊区，因为中心区一般被视为一个城市经济发展的“心脏”，它在地理位置、交通和文化等方面都占有有利因素，不仅可增强生产要素、人口和产业聚集的力量，也有利于市场的发展。因此，中部地区正在成为服务行业的主要区域（李2007）。本文在分析杭州中心城区的服务业竞争力的基础上，进行了相关的评价，旨在寻找到一种有效的策略以提高城市的服务行业发展。 2. 服务产业竞争力的文献研究 大部分关于服务行业的竞争力的学术研究都是基于它们的地区竞争能力之上的。因此，服务业的竞争力可以简单地定义为“服务行业在竞争中获取和利用资源的能力”。国外的研究学者更倾向于特定的服务行业的竞争力分析与研究，如商业服务行业（2001年Rubalcaba和加戈）、保险业（哈德威克和窦1998）、知识密集服务（1999年Windrum和汤姆林森）。然而，在中国，学者们的研究重点则集中于一个特定的区域，而不是一个特定的行业，如中国的31个主要省份（吴2003），中国六大发展先进的省份（2004年刁、庄），中国16个主要省份（2005年苏、张）。由于很多的因素都可以影响服务业的竞争力和复杂性，大多数中国学者认为，我们应该建立一个多层次的综合评价指标体系，如“总目标指导指数”。
汽车制动系统(机械、车辆工程毕业论文英文文献及翻译)
Automobile Brake System汽车制动系统 The braking system is the most important system in cars. If the brakes fail, the result can be disastrous. Brakes are actually energy conversion devices, which convert the kinetic energy (momentum) of the vehicle into thermal energy (heat).When stepping on the brakes, the driver commands a stopping force ten times as powerful as the force that puts the car in motion. The braking system can exert thousands of pounds of pressure on each of the four brakes. Two complete independent braking systems are used on the car. They are the service brake and the parking brake. The service brake acts to slow, stop, or hold the vehicle during normal driving. They are foot-operated by the driver depressing and releasing the brake pedal. The primary purpose of the brake is to hold the vehicle stationary while it is unattended. The parking brake is mechanically operated by when a separate parking brake foot pedal or hand lever is set. The brake system is composed of the following basic components: the “master cylinder” which is located under the hood, and is directly connected to the brake pedal, converts driver foot’s mechanical pressure into hydraulic pressure. Steel “brake lines” and flexible “brake hoses” connect the master cylinder to the “slave cylinders” located at each wheel. Brake fluid, specially designed to work in extreme conditions, fills the system. “Shoes” and “pads” are pushed by the slave cylinders to contact the “drums” and “rotors” thus causing drag, which (hopefully) slows the c ar. The typical brake system consists of disk brakes in front and either disk or drum brakes in the rear connected by a system of tubes and hoses that link the brake at each wheel to the master cylinder (Figure). Basically, all car brakes are friction brakes. When the driver applies the brake, the control device forces brake shoes, or pads, against the rotating brake drum or disks at wheel. Friction between the shoes or pads and the drums or disks then slows or stops the wheel so that the car is braked.