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  • So what does it mean for a machine to be athletic?

    機器的運動能力好是什麼意思?

  • We will demonstrate the concept of machine athleticism

    我們將展示機器運動能力的概念

  • and the research to achieve it

    以及為了實現而進行的研究

  • with the help of these flying machines called quadrocopters,

    靠的是這些飛行機器,叫做「四軸飛行器」 (quadrocopters)

  • or quads, for short.

    簡稱為「四軸」

  • Quads have been around for a long time.

    四軸已經存在很久了

  • The reason that they're so popular these days

    最近很受歡迎的原因

  • is because they're mechanically simple.

    是因為在機械方面很簡單

  • By controlling the speeds of these four propellers,

    只要控制這四個螺旋槳的速度

  • these machines can roll, pitch, yaw,

    這些機器可以側滾,俯仰,偏擺

  • and accelerate along their common orientation.

    以及沿著共同方向加速

  • On board are also a battery, a computer,

    上面還有電池及一台電腦

  • various sensors and wireless radios.

    各種感測器和無線收發器

  • Quads are extremely agile, but this agility comes at a cost.

    四軸極為靈活,但要付出代價

  • They are inherently unstable, and they need some form

    它本質上不穩定,需要某種形式的

  • of automatic feedback control in order to be able to fly.

    自動回饋控制,才可能飛行

  • So, how did it just do that?

    要怎麼做到這點呢?

  • Cameras on the ceiling and a laptop

    天花板上的攝影機和一台筆記型電腦

  • serve as an indoor global positioning system.

    就像是室內的全球定位系統

  • It's used to locate objects in the space

    用來為物體在空間中定位

  • that have these reflective markers on them.

    物體上有這些反光標記

  • This data is then sent to another laptop

    定位資料送到另一台筆記型電腦

  • that is running estimation and control algorithms,

    執行估計與控制的演算法

  • which in turn sends commands to the quad,

    再反過來把命令送到四軸

  • which is also running estimation and control algorithms.

    四軸本身也在執行估計與控制的演算法

  • The bulk of our research is algorithms.

    我們的研究大部分都是演算法

  • It's the magic that brings these machines to life.

    演算法是使這些機器活過來的魔法

  • So how does one design the algorithms

    要怎麼設計演算法

  • that create a machine athlete?

    才能創造出機器運動員?

  • We use something broadly called model-based design.

    我們使用的方法泛稱為模型化基礎設計

  • We first capture the physics with a mathematical model

    我們首先用數學模型捕捉

  • of how the machines behave.

    機器行為的物理法則

  • We then use a branch of mathematics

    然後用數學的一個分支—

  • called control theory to analyze these models

    「控制理論」來分析這些模型

  • and also to synthesize algorithms for controlling them.

    並合成控制的演算法

  • For example, that's how we can make the quad hover.

    例如我們想讓四軸原地懸停

  • We first captured the dynamics

    我們首先捕捉動態

  • with a set of differential equations.

    是一組微分方程式

  • We then manipulate these equations with the help

    然後操縱這些方程式

  • of control theory to create algorithms that stabilize the quad.

    在控制理論建立的演算法幫忙下讓四軸得以穩定

  • Let me demonstrate the strength of this approach.

    讓我展示這種方法的優點

  • Suppose that we want this quad to not only hover

    假設我們希望四軸不止是懸停

  • but to also balance this pole.

    還要讓桿子平衡

  • With a little bit of practice,

    經過一些練習

  • it's pretty straightforward for a human being to do this,

    人類很容易可以做到

  • although we do have the advantage of having

    雖然我們有優勢

  • two feet on the ground

    雙腳可以著地

  • and the use of our very versatile hands.

    還有極為靈活的手

  • It becomes a little bit more difficult

    像這樣就有點困難:

  • when I only have one foot on the ground

    如果只有一腳著地

  • and when I don't use my hands.

    而且不准用手

  • Notice how this pole has a reflective marker on top,

    請注意,桿子頂上有反光標記

  • which means that it can be located in the space.

    表示可在空間中定到它的位置

  • (Applause)

    (掌聲)

  • You can notice that this quad is making fine adjustments

    你可以看到,這架四軸正進行微調

  • to keep the pole balanced.

    以讓桿子保持平衡

  • How did we design the algorithms to do this?

    我們是怎麼設計演算法來做到的?

  • We added the mathematical model of the pole

    我們加入了桿子的數學模型

  • to that of the quad.

    到四軸中

  • Once we have a model of the combined quad-pole system,

    一旦我們有了結合四軸與桿子的模型

  • we can use control theory to create algorithms for controlling it.

    就可以用控制理論建立控制的演算法

  • Here, you see that it's stable,

    這裡,你看,很穩定

  • and even if I give it little nudges,

    就算我輕輕推一下

  • it goes back to the nice, balanced position.

    它仍可回到完全平衡的位置

  • We can also augment the model to include

    我們還可以加強模型,以包括

  • where we want the quad to be in space.

    我們希望四軸在空間的位置

  • Using this pointer, made out of reflective markers,

    用這根有反光標記的指示棒

  • I can point to where I want the quad to be in space

    可以指出我要四軸到的位置

  • a fixed distance away from me.

    和我保持固定的距離

  • The key to these acrobatic maneuvers is algorithms,

    這些特技動作的關鍵是演算法

  • designed with the help of mathematical models

    它的設計要靠數學模型

  • and control theory.

    與控制理論

  • Let's tell the quad to come back here

    我要告訴四軸回來這裡

  • and let the pole drop,

    並讓桿子倒下來

  • and I will next demonstrate the importance

    接下來我要展示

  • of understanding physical models

    了解物理模型、

  • and the workings of the physical world.

    以及實體世界運作的重要性

  • Notice how the quad lost altitude

    注意四軸的高度降低了

  • when I put this glass of water on it.

    我把這杯水放上去

  • Unlike the balancing pole, I did not include

    不像平衡桿,我並未把玻璃杯

  • the mathematical model of the glass in the system.

    的數學模型加到系統裡

  • In fact, the system doesn't even know that the glass of water is there.

    事實上,系統根本不知道有杯水

  • Like before, I could use the pointer to tell the quad

    我一樣可以用指示棒來告訴四軸

  • where I want it to be in space.

    我希望它在空間中的位置

  • (Applause)

    (掌聲)

  • Okay, you should be asking yourself,

    好吧,你應該問自己

  • why doesn't the water fall out of the glass?

    為什麼杯中的水不會灑出來?

  • Two facts: The first is that gravity acts

    兩個事實:第一點是重力

  • on all objects in the same way.

    對所有的物體作用相同

  • The second is that the propellers are all pointing

    第二點是,推進器都指向

  • in the same direction of the glass, pointing up.

    和杯子相同的方向,也就是向上

  • You put these two things together, the net result

    兩個原因加在一起,最終結果是

  • is that all side forces on the glass are small

    玻璃杯各方向的側向力都很小

  • and are mainly dominated by aerodynamic effects,

    還是以空氣動力學效應為主

  • which as these speeds are negligible.

    因此這些速度是微不足道的

  • And that's why you don't need to model the glass.

    這就是為什麼不需要杯子的模型

  • It naturally doesn't spill no matter what the quad does.

    水自然不會灑出來不管四軸怎麼動

  • (Applause)

    (掌聲)

  • The lesson here is that some high-performance tasks

    這裡學到的是,有些高性能任務

  • are easier than others,

    比其他的容易

  • and that understanding the physics of the problem

    還有,理解問題背後的物理

  • tells you which ones are easy and which ones are hard.

    可告訴我們哪些容易、哪些困難

  • In this instance, carrying a glass of water is easy.

    以此為例,載運水很容易

  • Balancing a pole is hard.

    平衡桿子則很困難

  • We've all heard stories of athletes

    我們都聽過運動員的故事

  • performing feats while physically injured.

    雖然身體受傷,仍然完成壯舉

  • Can a machine also perform

    機器可以在

  • with extreme physical damage?

    受重傷的情況下運作嗎?

  • Conventional wisdom says that you need

    傳統觀念認為,你需要

  • at least four fixed motor propeller pairs in order to fly,

    至少四個固定的馬達螺旋槳才能飛

  • because there are four degrees of freedom to control:

    因為有四個自由度要控制:

  • roll, pitch, yaw and acceleration.

    側滾、俯仰、偏擺、加速

  • Hexacopters and octocopters, with six and eight propellers,

    六軸和八軸分別有六和八個螺旋槳

  • can provide redundancy,

    可提供冗餘

  • but quadrocopters are much more popular

    但四軸則普及多了

  • because they have the minimum number

    因為它具有最小數目的

  • of fixed motor propeller pairs: four.

    固定馬達螺旋槳:四個

  • Or do they?

    是這樣嗎?

  • If we analyze the mathematical model of this machine

    我們分析這台機器的數學模型

  • with only two working propellers,

    如果只有兩個螺旋槳可運作

  • we discover that there's an unconventional way to fly it.

    我們發現有種非傳統的方式可飛行

  • We relinquish control of yaw,

    我們放棄控制偏擺

  • but roll, pitch and acceleration can still be controlled

    仍然可以控制側滾、俯仰、加速

  • with algorithms that exploit this new configuration.

    只要演算法能處理這種新配置

  • Mathematical models tell us exactly when

    數學模型告訴我們何時

  • and why this is possible.

    和為何這是可能的

  • In this instance, this knowledge allows us to design

    此例中,這種知識讓我們能設計出

  • novel machine architectures

    新穎的機器架構

  • or to design clever algorithms that gracefully handle damage,

    或優雅應對損害的巧妙演算法

  • just like human athletes do,

    就像人類運動員

  • instead of building machines with redundancy.

    而不必建構具有冗餘的機器

  • We can't help but hold our breath when we watch

    我們不禁屏住呼吸

  • a diver somersaulting into the water,

    當我們看到跳水選手翻個筋斗入水、

  • or when a vaulter is twisting in the air,

    或撐竿跳選手在空中扭轉、

  • the ground fast approaching.

    同時快速接近地面

  • Will the diver be able to pull off a rip entry?

    跳水選手入水時能否成功壓水花?

  • Will the vaulter stick the landing?

    撐竿跳選手能否完美著地?

  • Suppose we want this quad here

    假設我們希望四軸

  • to perform a triple flip and finish off

    表演三轉空翻,並結束在

  • at the exact same spot that it started.

    開始的同一地點

  • This maneuver is going to happen so quickly

    這個動作太快了

  • that we can't use position feedback to correct the motion during execution.

    無法用位置回饋信號糾正執行過程中的動作

  • There simply isn't enough time.

    時間根本不夠

  • Instead, what the quad can do is perform the maneuver blindly,

    相反的,四軸只能盲目進行動作

  • observe how it finishes the maneuver,

    觀察四軸如何完成動作

  • and then use that information to modify its behavior

    再用這些資訊來修改行為

  • so that the next flip is better.

    讓下次空翻更進步

  • Similar to the diver and the vaulter,

    就像跳水選手和撐竿跳選手

  • it is only through repeated practice

    只有通過反覆練習

  • that the maneuver can be learned and executed

    才能學會動作

  • to the highest standard.

    並達到最完美的境界

  • (Applause)

    (掌聲)

  • Striking a moving ball is a necessary skill in many sports.

    打擊移動中的球對許多運動是必要技能

  • How do we make a machine do

    我們如何讓一台機器做出

  • what an athlete does seemingly without effort?

    對運動員看似毫不費力的動作?

  • (Applause)

    (掌聲)

  • This quad has a racket strapped onto its head

    這架四軸頂部綁了個球拍

  • with a sweet spot roughly the size of an apple, so not too large.

    甜蜜點大約一個蘋果大小所以不會太大

  • The following calculations are made every 20 milliseconds,

    以下的計算每二十毫秒執行一次

  • or 50 times per second.

    也就是每秒執行五十次

  • We first figure out where the ball is going.

    我們首先弄清楚球會飛到哪裡

  • We then next calculate how the quad should hit the ball

    然後計算四軸如何擊中球

  • so that it flies to where it was thrown from.

    四軸飛到球丟出的附近

  • Third, a trajectory is planned that carries the quad

    第三,規劃出四軸由目前位置

  • from its current state to the impact point with the ball.

    到擊球位置的軌道

  • Fourth, we only execute 20 milliseconds' worth of that strategy.

    第四,只需執行這戰略二十毫秒

  • Twenty milliseconds later, the whole process is repeated

    二十毫秒過後,再重複整個過程

  • until the quad strikes the ball.

    直到四軸擊中球

  • (Applause)

    (掌聲)

  • Machines can not only perform dynamic maneuvers on their own,

    機器不僅可以自主執行動態操作

  • they can do it collectively.

    還可以互相合作

  • These three quads are cooperatively carrying a sky net.

    這三架四軸合作張開網子

  • (Applause)

    (掌聲)

  • They perform an extremely dynamic

    它們執行的,是非常動態

  • and collective maneuver

    且需要合作的動作

  • to launch the ball back to me.

    把球丟回給我

  • Notice that, at full extension, these quads are vertical.

    請注意的,在完全伸展時這些四軸是垂直的

  • (Applause)

    (掌聲)

  • In fact, when fully extended,

    事實上,在完全伸展時

  • this is roughly five times greater than what a bungee jumper feels

    大約產生五倍於高空彈跳

  • at the end of their launch.

    最低點的力量

  • The algorithms to do this are very similar

    做到這點的演算法非常相似於

  • to what the single quad used to hit the ball back to me.

    單一四軸把球打回我身邊

  • Mathematical models are used to continuously re-plan

    使用數學模型不斷重新規劃

  • a cooperative strategy 50 times per second.

    合作策略,每秒五十次

  • Everything we have seen so far has been

    到目前為止,我們看到的一切

  • about the machines and their capabilities.

    都是關於機器及其功能

  • What happens when we couple this machine athleticism

    我們若把這台機器的運動能力

  • with that of a human being?

    和人結合,會發生什麼事?

  • What I have in front of me is a commercial gesture sensor

    在我面前的是一具商業的人體動作感測器

  • mainly used in gaming.

    主要用於遊戲(Kinect)

  • It can recognize what my various body parts

    可以即時識別我身體

  • are doing in real time.

    各部位的動作

  • Similar to the pointer that I used earlier,

    就像剛才我用指示棒

  • we can use this as inputs to the system.

    我們可用這個作為系統的輸入

  • We now have a natural way of interacting

    我們就有了自然的互動方式

  • with the raw athleticism of these quads with my gestures.

    用我的手勢和四軸的原始運動能力互動

  • (Applause)

    (掌聲)

  • Interaction doesn't have to be virtual. It can be physical.

    互動不一定是虛擬也可以是實體的

  • Take this quad, for example.

    以此四軸為例

  • It's trying to stay at a fixed point in space.

    它試著要待在空間裡固定的一點

  • If I try to move it out of the way, it fights me,

    如果我試著將它移開,它會抵抗

  • and moves back to where it wants to be.

    並移回它想待的地方

  • We can change this behavior, however.

    但我們可以改變這種行為

  • We can use mathematical models

    我們可以用數學模型

  • to estimate the force that I'm applying to the quad.

    估算出我對四軸施力的大小

  • Once we know this force, we can also change the laws of physics,

    一旦知道了力量大小我們也可以改變物理規則

  • as far as the quad is concerned, of course.

    當然是對四軸而言

  • Here the quad is behaving as if it were

    這架四軸的行為就好像它

  • in a viscous fluid.

    在黏性流體中一樣

  • We now have an intimate way

    我們現在有了親密的方式

  • of interacting with a machine.

    可與機器互動

  • I will use this new capability to position

    我要用這新功能把載著相機的四軸

  • this camera-carrying quad to the appropriate location

    定位到適當位置

  • for filming the remainder of this demonstration.

    以拍攝接下來的示範

  • So we can physically interact with these quads

    我們可以與四軸進行實體互動

  • and we can change the laws of physics.

    我們也可以改變物理定律

  • Let's have a little bit of fun with this.

    讓我們來玩一下

  • For what you will see next, these quads

    接下來你會看到這些四軸

  • will initially behave as if they were on Pluto.

    一開始像是在冥王星的引力

  • As time goes on, gravity will be increased

    隨著時間過去,重力逐漸增加

  • until we're all back on planet Earth,

    直到全都回到地球的引力

  • but I assure you we won't get there.

    但我保證不會發生

  • Okay, here goes.

    好的,開始

  • (Laughter)

    (笑聲)

  • (Laughter)

    (笑聲)

  • (Applause)

    (掌聲)

  • Whew!

    呼!

  • You're all thinking now,

    各位現在可能在想

  • these guys are having way too much fun,

    這些傢伙也太愛玩了吧

  • and you're probably also asking yourself,

    你可能也在問自己

  • why exactly are they building machine athletes?

    他們到底為何要建造機械運動員?

  • Some conjecture that the role of play in the animal kingdom

    一個推測是,就像動物王國中遊戲的作用

  • is to hone skills and develop capabilities.

    可以磨練技能和發展能力

  • Others think that it has more of a social role,

    其他人則認為這有更多的社會角色

  • that it's used to bind the group.

    可讓團體聚在一起

  • Similarly, we use the analogy of sports and athleticism

    同樣,我們用運動和運動能力類比

  • to create new algorithms for machines

    來建立機器的新演算法

  • to push them to their limits.

    將其能力推昇到極限

  • What impact will the speed of machines have on our way of life?

    機器的速度會對我們的生活方式產生什麼影響?

  • Like all our past creations and innovations,

    就像我們過去的各種創作及創新