But this train is unlike any other before it.

但這列火車不同於以往的任何火車，

It doesn't have wheels.

它沒有輪子。

It hovers on a cushion of air, and because of that, it can travel efficiently at very

它懸浮在一層如同軟墊的空氣上。也因為 如此，它可以非常有效地

high speeds.

高速行駛。

Maybe, you've never heard of hovertains, but by the 1970's, they were seriously being

也許，你從來沒有聽說過Hovertains(懸浮列車)， 但到了1970年代，他們被認為

considered as the solution to slow, antiquated railways

是緩慢，過時鐵路的解決方案而受到重視。

which, in many countries were in decline.

在許多國家，也受到認同。

In the 1960's, railways were in trouble.

在1960年代，鐵路陷入困境。

In developed countries, ridership was plummeting and railways were in decline.

在已開發國家，乘客量急劇下降 ,鐵路也逐漸沒落。

In Britain, some routes were still served by steam locomotives.

在英國，還有一些路線在使用蒸氣火車頭。

And the public was beginning to view rail as slow and outdated.

而社會大眾認為鐵路是緩慢而過時的。

Trains now had to compete with newly built superhighways and intercity air travel.

且火車必須與新建的高速公路和國內線班機競爭。

And even Japan's newly introduced Bullet Train, a technical marvel for 1964, was initially

甚至是日本新推出的子彈列車-這個1964年的技術奇蹟，

only running at speeds of up to 130 miles an hour.

也只能以130英里(約209km/h)的速度行駛。

Part of the problem was most rail lines in the developed world, were built a half century

大部分問題在於，大多數在已開發國家的鐵路，都建於半個世紀以前，

earlier, with their sharp twists and curves, they just weren't built for speed.

鐵路的大角度轉彎和彎道，都不是為了高速而設計。

But the trains also had a problem.

但火車本身也有問題。

And it had to do with the shape of their wheels.

這與輪子的形狀有關。

Train wheels are not perfectly cylindrical, they're cone-like in shape.

火車輪子不是完美的圓柱形， 是呈錐形。

And this is what keeps them on their track, especially around curves.

這是為了讓他們保持在軌道上，特別是遇到彎道時。

While the wheels also have flanges, these are really just a backup in case limits of

雖然車輪有凸緣，但這些只是一個預防的措施

that conical shape are exceed.

避免車輪達到極限值而出軌。

The conical shape of train wheels is a brilliant innovation.

圓錐形的車輪在當初是一個聰明的革新。

But there's a problem, and it's called Hunting Oscillation.

但是它有一個問題，被稱為振盪。

At higher speeds, the cone-like shape causes a train to increasingly rock from side to side.

在高速下，錐形會導致火車的搖晃越來越大。

The flanges start hitting the track, which increases resistance, making higher speeds

邊緣開始撞擊軌道，增加阻力，

inefficient and causing wear and damage.

使得高速行駛缺乏效率，並導致磨損。

Given enough speed, Hunting Oscillation can even cause a train to derail itself, on a

如果有足夠的速度，震盪甚至可以導致火車自脫軌，即便

perfectly straight track.

在直線上。

This meant that trains essentially had a speed limit built right into their basic design.

這意味著火車的設技從基礎上限制了火車的極速

So in the 1960's, the thinking was that maybe it was time to get rid of wheels all together.

所以在20世紀60年代，人們的想法就是: 也許是時候把車輪全部拆掉了。

The French have already built the Aerotrain. Designed to reduce the running

法國人已經建造了Aerotrain。 設計上透過移除車輪，

friction problems of wheeled trains by doing away with the wheels.

解決列車的摩擦問題。

It's called a hovertrain.

它被稱為hovertrain。

By feeding high pressure air through lifting pads, the train would float on a cushion of

透過將高壓空氣注車底， 火車就像漂浮在氣墊上，

air much like a hovercraft.

就像氣墊船。

The track would act merely as a guideway.

軌道的作用就僅僅是一條導軌。

Without the rolling resistance of wheels, a hovertrain promised efficiency and much

沒有車輪的阻力， hovertrain保證了高效率

higher speeds.

和更高的速度。

And leading the way for this promising technology was a French engineer named Jean Bertin.

令這項有前景的技術引領潮流的， 是一位名叫Jean Bertin的法國工程師。

By 1973, Bertin and his team had built a hovertrain that could carry 80 passengers.

1973年，Bertin和他的團隊建造了一台可以容納80名乘客的hovertrain

French officials and the media marveled at its combination of speed and smooth ride.

法國政府和媒體對它的速度和穩定性感到驚訝

Bertin called his designs Aerotrains.

Bertin稱他的設計為Aerotrains。

Over the years, he had worked tirelessly to develop several prototypes, proving the viability

多年來，他不斷地開發更多原型機，證明這個概念的可行性

of the concept.

每次成功，他都獲得一些政府的資助。

With each success, he secured a healthy dose of government funding.

最先進的Aerotrain是由 來自飛機的渦輪扇引擎驅動。

The most advanced Aerotrain was powered by a turbofan.

它能產生超過一萬二千磅的推力。

pretty much straight off an airliner.

在前面，400馬力的燃氣輪機 提供高壓空氣來徘懸浮這台二十噸重的車廂

It produced over twelve thousand pounds of thrust.

使車廂離導軌四分之一英寸

At the front, a 400 horse power gas-turbine supplied high-pressure air to hover this twenty

而導軌，基本上由混凝土製成。

tonne loaded train a quarter of an inch off its guideway.

Aerotrain可以輕易、完美地懸浮。

And the guideway, was essentially poured concrete.

這也意味著hovertrain導軌比起傳統的鐵軌更容易建造

An Aerotrain could easily hover over imperfections.

維護成本更低。

That meant that hovertrain lines were potentially easier to build than conventional rail and

1974年3月5日，Aerotrain證明了它可以將近時速260英里前進

cheaper to maintain.

且如果導軌更長，它可以開得更快。

On March 5, 1974, an Aerotrain proved it could travel at nearly two hundred and sixty miles

Bertin原型的成功開啟了 法國各地的Aerotrain計劃。

per hour.

打破錄後幾個月後

And it might have gone even faster, had its test track had been longer.

第一條線的建造合約簽訂。

The success of Bertin's prototypes led to plans for Aerotrain links throughout France.

法國之外，世界也在注意。

And just a couple months after the record breaking speed-run, a contract was signed

英國-發明了氣墊船的國家， 也看到hovertrain的巨大潛力

to begin construction of the very first line.

他們在1970年開始屬於他們的的hovertrain測試

Outside of France, the world was also taking note.

而在某些方面，英國的研究的 hovertrains更加先進。

The British, who had invented the hovercraft, could see the enormous potential of hovertrain

他們的原型，RTV-31履帶式氣墊船 圍繞在另一項重要創新設計。

technology.

線性感應發動機。

They constructed their own hovertrain test track in 1970.

雖然Bertin也嘗試過線性感應發動機，

And in some ways, Britain's research into hovertrains was even more advanced.

大多數Aerotrains都是以風扇或噴氣式推進。

Their prototype, the RTV-31 Tracked Hovercraft was designed around another important innovation.

但直線感應發動機的效率更高。

The Linear Induction Motor.

和傳統的旋轉電機不同，它提供了線性推進力

Although Bertin also experimented with Linear Induction Motors, most of his Aerotrains were

沒有渦輪風扇的噪音或污染。

fan or jet propelled.

英國的目標是建設一個可以在時速200和250英里之間的交通工具系統

But a Linear Induction Motor is more efficient.

美國也不甘示弱， 也在研究hovertrain技術。

Instead of the rotary movement of a conventional motor, it provides a linear force for forward

1965年，"高速地面運輸"法案通過。

movement.

這是為了將更快的鐵路系統引進美國。

Without any of the noise or pollution of a turbofan running at ground level.

資金用於開發新技術 或是獲得Bertin的Aerotrain設計授權。

The British were aiming to build a transportation system that could travel at two hundred and

各種hovertrain的原型被開發出來， 一些由線性感應發動機驅動，其他由渦輪引擎驅動。

fifty miles per hour.

但最先進的原型是Urban的履帶式氣墊車。

The Americans, not ones to be outdone were also researching hovertrain technologies.

其光滑的外觀和無窗駕駛艙，它看起來肯定很快。

In 1965, the High Speed Ground Transportation Act was passed.

但它設計用於在人口稠密地區運送大量旅客，最高速度約為時速150英里

It was an effort to introduce faster rail to America.

履帶式氣墊車是一個已經完整開發的原型車。

Funding was put towards developing new technologies and even licensing Bertin's Aerotrain designs.

經常在科羅拉多州普韋布洛的賽道上進行測試。

Various hovertrain prototypes were developed, some powered by Linear Induction Motors, others

在20世紀70年代初，hovertrains 看起來有望徹底改變鐵路。

by Jets.

但僅僅幾年之後，沒有一個國家繼續研究這項技術。

But the most developed prototype was the Urban Tracked Air Cushion Vehicle.

Aerotrain野心勃勃的"貫穿法國計畫" 從未實現。

With its sleek windowless cockpit and Blade Runner styling, it certainly looks fast.

今天只剩下被遺棄的測軌道。

It was designed to operate in heavily travelled urban areas and had a top speed of about 150

1970年代的全球經濟衰退壓力使 政府削減了這些富有為野心的運輸計畫的資金

miles per hour.

還有一些關鍵的技術挑戰 未被克服。

The Tracked Air Cushion Vehicle was a fully developed prototype that underwent regular

在高速行駛時，hovertrains比傳統列車更有效率。

testing on its track in Pueblo, Colorado.

但在低速下，他們沒有贏的機會。

At the start of the 1970's, hovertrains looked poised to revolutionize rail.

但這並不是他們失敗的主要原因。

But just a few years later, not a single country was pursuing the technology.

在1970年代，第一輛磁浮列車已經在開發。

Ambitious plans for Aerotrain links throughout France never materialized.

他們使用電磁鐵懸浮在導軌上，而不是使用壓縮空氣

All that's left today are the abandoned test tracks.

因此磁浮列車比hovertrains更有效率。

A global recession in the 1970's pressured governments to cut funding for ambitious transportation

但磁浮列車也未能徹底改革鐵路。

projects.

經過近四十年，也只有一些在營運。

And some critical technical challenges were never really worked out.

今天的高速鐵路基本上仍然是傳統的輪式列車。

At high speeds, hovertrains could travel more efficiently than conventional trains but at

事實證明，鐵路革新並不是通過一次革命性的技術飛躍，

low speeds, they wouldn't stand a chance.

而是通過改進現有的鐵路網絡。

But that's not really why they failed.

現代化的鐵軌設計得可以承受更高的速度

In the 1970's, the first maglev train were already in development.

新的信號技術、更高級的阻尼。

They would use electromagnets to levitate over a guideway instead hovering using high

精密加工的車輪和偏航阻尼 使得具有較小錐角的車輪成為可能。

pressure air.

這減少了振盪的問題。

And so Maglevs promised even greater efficiency and speed over hovertrains.

法國轉而投資他們的高速TGV鐵路系統，

But Maglev's also failed to revolutionize rail.

今日以時素200英里的速度行駛。

After nearly four decades, there's only a handful of them operating in the world.

英國人提出了獨特的解決方案:

High speed rail today is still based largely on conventional wheeled trains.

一列可以傾斜到的列車，可以在轉彎時以更高的速度行駛。

It turns out that the problems of railways were overcome not by one revolutionary leap

至於美國，至少在那時候，大部分時間都花費在汽車上

forward, but by incremental improvements.

Hovertrains或Maglevs或任何其他革命性的鐵路替代品必須與約一百萬英里的現有鐵路競爭。

Existing rail networks were modernized with sections of track that could handle higher

車站和基礎設施的建設都已經存在於 幾乎世界上每個城市。

speeds.

事實證明，將新想法溶入現有的技術，比讓世界融入新想法更簡單。

New signaling technologies were developed along with more advanced suspensions.

這就是為什麼改進現有技術的方案，最後通常會勝出。

Precision machined wheels and yaw dampers allowed for train wheels with less cone angle.

然而，有一個新的解決方案，

And that reduced the hunting oscillation problem.

列車在一種條新的軌道上行使，

Instead of Aerotrains, the French invested in their high speed TGV rail service, which

軌道實際上是一個減壓的管道，所以 摩擦力和空氣阻力較小。

today routinely travels at 200 miles per hour.

由線性感發動機機和空氣壓縮驅動。

The British came up with unique solutions like a train that could tilt into corners

它宣稱可以時速700英里前進。

and take sharp curves more quickly.

它的管狀軌道可以懸掛或地下...。

The Americans, at least for the time being, mostly stuck with cars.

我在這個影片中使用了一些抽象的術語， 像摩擦，滾動阻力和磁力。

Hovertrains or Maglevs or any other radical alternative to rail has to compete with nearly

這些基本觀念 對理解機器如何運作至關重要，

a million miles of rail line already in existence.

無論是hovertrain，還是超音速噴射機。

With stations and infrastructure built-out in nearly every city in the world.

將概念和公式記憶，和實際上的理解是兩回事。 而後者，才是日常生活中真正有用的。

Turns out, it's easier to adapt new ideas to the existing world than to have the world

這就是我喜歡Brilliant.org的原因。它 不僅僅幫助高效的學習數學和科學，

adapt to radical new ideas.

還很有趣。

Which is why incremental improvements often win out in the end.

Brilliant讓你參與其中， 透過解決問題來學習

Although, there's a new solution in the works.

而不只是聽課程和記筆記。

A train runs in a new kind of track.

他加強你的推理、創造力、 和解決問題的技巧，這是生活中不可或缺的。

It's actually a reduced pressure-tube, so there's less friction and air resistance.

一個開學習物理學基石的好地方: ()

Driven by linear induction motors and air compressors.

到Brilliant.org/mustard註冊並開始吧

It promises to travel at over 700 miles per hour.

此外，前200名將獲得20％的 年度高級訂閱折扣

It's tube-like tracks could suspended or underground [voice fades out].

I used some conceptual terms in this video, like friction, rolling resistance and magnetism.

These are foundational concepts, the kind that is crucial to understanding how machines

work, whether it's a hovertrain, or supersonic jet.

But it's one thing to be made to memorize a concept and the formulas, and another to

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A great place to start acquiring the critical building blocks for understanding physics

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