自平衡单轨列车：英语精读讲义

This is the Brennan Monorail,

这是布伦南单轨列车，

a train from the early 1900s

一列来自20世纪初的火车，

that seemed to defy the laws of physics. 習語

它似乎打破了物理定律。

Not only did it keep itself perfectly balanced on a single rail, 語法

它不仅能在单根轨道上保持完美的平衡，

but it mysteriously leaned into corners without any driver input. 短語搭配

而且在没有任何驾驶员输入的情况下，它还能神秘地倾斜着过弯。

This was a real invention,

这是一项真实的发明，

and it was unveiled to the public in 1910 短語搭配

由其发明者路易斯·布伦南

by its inventor Louis Brennan.

在1910年向公众展示。

The idea was that using a single rail instead of two 語法

他的想法是，使用单轨而不是双轨，

would make trains faster and railways cheaper to build.

可以使列车速度更快，铁路建造成本更低。

His train could take corners at greater speeds 短語搭配

他的列车可以以更高的速度转弯，

without being thrown off the tracks, 短語動詞

而不会被甩出轨道，

and his railway only needed half the material.

而且他的铁路只需要一半的材料。

Unlike the monorails we're familiar with today,

与我们今天熟悉的单轨列车不同，

which have thick tracks built high in the air,

现代的单轨列车有建在高空的厚重轨道，

Brennan's monorail could run on existing tracks.

但布伦南的单轨列车可以在现有的轨道上运行。

Although it looks a bit sketchy, 用詞

虽然它看起来有些简陋，

it was by design very stable. 短語搭配

但其设计非常稳定。

At the heart of the train 習語

列车的核心部分

was a gyroscope that could correct the train's tilt

是一个陀螺仪，它能纠正列车的倾斜，

before the passengers even noticed.

甚至在乘客察觉之前就已完成。

This was a mind-blowing piece of engineering,

这是一项令人惊叹的工程杰作，

especially for 1910.

尤其是在1910年。

But how did it actually work?

但它究竟是如何工作的呢？

We modeled the entire thing and studied the original patents

我们对整个装置进行了建模，并研究了最初的专利，

to show you how incredibly clever this design was.

向你展示这项设计有多么巧妙。

But in order to understand exactly what's going on here, 講解

但为了弄清楚这里到底发生了什么，

we need to know a bit about gyroscopes.

我们需要先了解一点关于陀螺仪的知识。

The basic principle is that if you spin a disc really quickly,

基本原理是，如果你极快地旋转一个圆盘，

its angular momentum tries to keep it perfectly stable.

它的角动量会试图让它保持完美的稳定。

If you try to tilt it in this direction,

如果你试着朝这个方向倾斜它，

it starts rotating on the vertical axis.

它就会开始在垂直轴上旋转。

This is called precession. 表達脈絡

这被称为进动。

But if instead of tilting it,

但是，如果我们不是去倾斜它，

we cause it to precess,

而是让它产生进动，

it actually tilts the disc in the opposite direction.

它实际上会使圆盘向相反的方向倾斜。

It's because of this that a gyro will always try

正是因为如此，陀螺仪总是会试图

to find its way back to equilibrium. 短語搭配

找回它的平衡状态。

Brennan saw this as the key to keeping his train balanced, 短語搭配

布伦南认为这是保持列车平衡的关键，

and so he experimented by placing a small flywheel

因此他做了一个实验，把一个小飞轮

in a model train and hooking it up to an electric motor. 短語動詞

放在模型火车里，并将其连接到电动机上。

Initially, this worked,

起初，这很有效，

and anytime the train started to fall,

每当火车开始倒下时，

the disc would precess and keep the train upright.

圆盘就会进动，使列车保持直立。

The problem was that when the train turned, 表達脈絡

问题是，当列车转弯时，

the gyro didn't turn with it,

陀螺仪并没有跟着转，

since it was trying to maintain its position in space.

因为它试图保持它在空间中的位置。

From the train's point of view, 短語搭配

从列车的角度来看，

the gyro was precessing,

陀螺仪正在进动，

which caused the train to tilt over and fall off the track.

这导致列车倾覆并脱轨。

To solve this problem,

为了解决这个问题，

Brennan put a second gyro in the train and made it spin in the opposite direction.

布伦南在列车上放置了第二个陀螺仪，并让它向相反方向旋转。

Both were connected by a gear,

两者由一个齿轮连接，

so that when one gyro precessed,

这样当一个陀螺仪进动时，

the other would precess in the exact opposite direction.

另一个会向完全相反的方向进动。

When the train turned a corner,

当列车转弯时，

both gyros wanted to keep facing the same way,

两个陀螺仪都想保持面向同一个方向，

but this was impossible.

但这显然是不可能的。

And so both gyros were forced to rotate with the train,

因此，两个陀螺仪被迫与列车一起旋转，

and this unwanted precession got canceled out. 短語動詞

这种不必要的进动就被抵消了。

With another problem solved, 語法

随着又一个问题得到解决，

he started working on the full-sized prototype that he could test with real passengers.

他开始致力于全尺寸原型的开发，以便用真实乘客进行测试。

This was a 12 m long,

这是一辆12米长、

22-ton vehicle with two massive gyros spinning at 3,500 rpm.

22吨重的车辆，配有两个以3500转/分旋转的巨大陀螺仪。

But scaling up his design uncovered a massive problem. 短語動詞

但放大他的设计暴露出了一个巨大的问题。

Now that some serious weight was involved, 語法

现在涉及到极大的重量，

the gyros weren't only fighting against their own rotation,

陀螺仪不仅要对抗自身的旋转，

but also the force of gravity trying to pull down the train.

还要对抗试图将列车拉倒的重力。

This was much easier to overcome in Brennan's smaller model,

这在布伦南较小的模型中很容易克服，

but with 22 tons now trying to pull the train over,

但现在有22吨的重量试图把列车拉倒，

the gyros had to be much stronger.

陀螺仪就必须强大得多。

The next day,

第二天，

while having lunch,

在吃午餐的时候，

a letter arrived that would have the key to the solution.

一封信送达了，它包含了解决方案的关键。

It was a letter from the King of Nigeria

那是一封来自尼日利亚国王的信，

saying that he had a large amount of money for Brennan.

说他有一大笔钱要给布伦南。

Just kidding,

开个玩笑，

this never happened.

这从未发生过。

But if it did,

但如果真的发生了，

Brennan could have asked Incogni today's sponsor to stop it. 語法

布伦南本来可以求助今天的赞助商 Incogni 来阻止它。

Every day,

每一天，

we constantly get bombarded with spam emails and phone calls 短語搭配

我们都会不断受到垃圾邮件和推销电话的轰炸，

from companies we never signed up to.

来自我们从未注册过的公司。

Why does this happen?

为什么会这样呢？

Well,

嗯，

data brokers sell our information to marketing agencies 文化背景

数据经纪人把我们的信息卖给营销机构，

who then send you all the stuff you don't want.

然后他们就把你不需要的东西发给你。

The worst thing is that all the information

最糟糕的是所有的信息

they have in their databases

他们在数据库中拥有的那些，

can quite easily be leaked or stolen by criminals.

很容易被犯罪分子泄露或窃取。

The good thing is that you have the right to protect yourself.

好消息是，你有权保护自己。

And so Incogni reaches out to all of these companies 短語動詞

于是，Incogni 会代表你

on your behalf and gets them to delete any information 講解

联系所有这些公司，并让他们删除

they have about you.

关于你的任何信息。

All you need to do is sign up,

你只需要注册，

sit back,

舒服地坐下，

and watch Incogni do their work.

看着 Incogni 完成他们的工作。

These are all the companies that no longer have my data.

这些都是不再拥有我数据的公司。

To protect your personal information and get rid of spam 短語動詞

为了保护你的个人信息

in your life,

并摆脱生活中的垃圾信息，

visit incogni.com/primalspace

请访问 incogni.com/primalspace，

and use the code primalspace to get 60% off.

并使用代码 primalspace 享受四折优惠。

In order for Brennan's monorail to keep itself perfectly balanced,

为了让布伦南单轨列车保持完美平衡，

it needed to overcome its own weight,

它需要克服自身的重量，

which was constantly trying to pull the vehicle over.

这股重量总是试图把车辆拉倒。

As it leaned,

随着它的倾斜，

the center of gravity shifted,

重心发生了偏移，

and the vehicle got pulled down more and more.

车辆被越拉越往下坠。

The natural precession wasn't strong or quick enough to keep the train stable.

自然的进动既不够强也不够快，无法保持列车稳定。

And so Brennan came up with a new solution. 短語動詞

于是布伦南想出了一个新方案。

He realized that the key to all of this

他意识到这一切的关键

was taking control of the gyro's precession.

是控制陀螺仪的进动。

By purposely precessing them quicker than they would normally precess, 語法

通过有意让它们比正常进动得更快，

a stronger force would be put into righting the vehicle.

就能产生更强的力量来扶正车辆。

He hooked up the gyros to a petrol engine

他将陀螺仪连接到汽油发动机上，

and encased them in vacuum-sealed casings to reduce friction.

并将它们封装在真空密封的壳体中以减少摩擦。

Even if the power ran out, 講解

即使动力耗尽，

the gyros would keep spinning for up to 30 minutes

陀螺仪也能继续旋转长达30分钟，

before the train could fall over.

在这之后列车才会倒下。

He placed the gyros on a single gimbal

他将陀螺仪放在一个万向节上，

that allowed the whole system to rotate on the train's roll axis.

这允许整个系统在列车的滚转轴上旋转。

The axles of each gyro stuck out of the casing

每个陀螺仪的转轴伸出壳体，

and sat between two guide plates that were attached to the train's chassis.

位于两块连接在列车底盘上的导向板之间。

As the train tipped over,

当列车倾斜时，

the axles would make contact with one of the plates, 短語搭配

这些转轴会接触到其中一块导向板，

and friction would cause them to roll over like a wheel on the ground. 表達脈絡

摩擦力会导致它们像地上的轮子一样滚动。

This would cause the gyros to precess much quicker than the previous design,

这会导致陀螺仪比以前的设计进动得快得多，

pushing the entire train back to equilibrium. 語法

从而将整辆列车推回平衡状态。

The problem was,

问题是，

vibrations would cause the gyros to bounce on the guide plates,

振动会导致陀螺仪在导向板上弹跳，

and they never produced a smooth and proportional force on the train.

它们从未在列车上产生过平滑且成比例的力。

And so Brennan got rid of the guide plates

因此，布伦南去掉了导向板，

and came up with an even better solution.

并想出了一个更好的解决方案。

He fixed the gyros to the train's chassis, 用詞

他把陀螺仪固定在列车底盘上，

so they would rotate with the train.

这样它们就会与列车一起旋转。

When the train tipped over,

当列车倾斜时，

the gyros did their usual thing and started to precess naturally.

陀螺仪照常发挥作用，开始自然进动。

On the right-hand gyro,

在右侧的陀螺仪上，

its axle was directly connected to a mechanism

它的转轴直接连接到一个机械装置，

that controlled an actuator rod.

该装置控制着一根致动杆。

This rod was linked to a lever and two valves,

这根杆连接到一个控制杆和两个阀门，

which controlled the flow of compressed air.

用于控制压缩空气的流动。

This compressed air followed two pipes

这些压缩空气顺着两根管道流动，

that entered into either end of a large tube 短語搭配

这两根管道分别接入一根大管子的两端，

running through the center of the gyroscope.

这根大管子贯穿陀螺仪的中心。

Inside this tube was a gear rack,

在这根管子内部是一根齿条，

which was placed between the two gyros

它放置在两个陀螺仪之间，

and could move back and forth to rotate them. 短語搭配

可以来回移动以使它们旋转。

When the train tilted,

当列车倾斜时，

the gyros would precess,

陀螺仪就会进动，

and the clever actuator arm would activate the valves.

巧妙的致动臂就会激活阀门。

By closing off one of the valves, 短語動詞

通过关闭其中一个阀门，

compressed air would then flow through one of the pipes

压缩空气就会流过其中一根管道，

and into one end of the tube.

进入管子的一端。

This would increase the pressure,

这会增加压力，

pushing the gear rack and forcing the gyros to precess in the opposite direction

推动齿条，迫使陀螺仪朝相反方向进动，

until the train returned to equilibrium.

直到列车恢复平衡。

This all happened instantly,

这一切都在瞬间发生，

and the gyros would react before the train ever got too unbalanced.

陀螺仪会在列车变得太不平衡之前就做出反应。

The key here is that the compressed air acted as a pneumatic system, 講解

这里的关键是压缩空气起到了气动系统的作用，

allowing the smaller force to produce a much bigger force.

允许用较小的力产生大得多的力。

The force of the compressed air gets sent equally through the air in the tube.

压缩空气的力通过管子里的空气被平均传递出去。

Once it gets to the larger piston, 語法

一旦它到达较大的活塞，

the same force is multiplied over a larger area.

同样的力会在更大的面积上成倍增加。

And so this piston is moved with much greater force

因此，这个活塞的移动力量

than the gyros put into it.

远大于陀螺仪输入给它的力量。

This genius system took the force of the train tipping over

这个天才的系统利用了列车倾斜的力，

and multiplied it against itself to create a train that always wanted to stay level.

并将其自身成倍放大，创造出了一列总是想要保持水平的列车。

His train was so strong that even if every passenger stood on one side, 語法

他的列车保持平衡的能力非常强，即使所有乘客都站在同一侧，

the train would stay perfectly balanced.

列车也会保持完美的平衡。

His prototype was a huge success,

他的原型取得了巨大的成功，

and at the time, it really did seem like the future. 語法

在当时，它确实看起来像是未来之光。

But, unfortunately, investors weren't confident in the design.

但是，不幸的是，投资者对这项设计没有信心。

Two-railed trains were already well-established at the time,

当时双轨列车已经非常成熟了，

and the fact that every train carriage would need its own gyroscope 語法

而且每节车厢都需要自己的陀螺仪这一事实，

brought the project to an end. 短語搭配

导致了该项目的终结。

Either way, it's amazing to uncover these incredible inventions 表達脈絡

不管怎样，能发掘出这些令人难以置信的发明

and appreciate the geniuses behind their creation.

并欣赏其创造背后的天才，是一件很棒的事。

And now, time for the Primal Space giveaway.

现在，是 Primal Space 的抽奖时间了。

The winner of the previous giveaway is Cameron.

上一次抽奖的获胜者是 Cameron。

Congrats.

恭喜。

In the next video, we'll be giving away another Primal Space Voyager poster 短語動詞

在下一个视频中，我们将把商店里有售的

available in our store to one lucky winner.

另一张 Primal Space 航海者海报送给一位幸运赢家。

All you need to do is sign up at the link below,

你只需要在下面的链接注册，

like the video, and leave a comment saying what you think about Brennan's design.

给视频点赞，并留言说出你对布伦南设计的看法。

Thank you very much for watching,

非常感谢你的观看，

and I'll see you in the next video.

我们下期视频再见。