英国皇家科学院圣诞讲座：让火花飞（2014）

我想让你
So what I want you to do is
把电池放到磁铁上面
just put that battery on top of that magnet.
行吗 如你所见 磁性很强
OK? So you see, it's a very strong magnet.
磁铁会形成一个磁场
So that magnet can set up a magnetic field.
然后我们把线圈拿到这里
Then we have our coil here,
如果我们把线圈放到电池上面
and if we place our coil over the top of that battery,
电池会产生电流
it will generate a current,
电流经过线圈
an electrical current, through our coil.
那么线圈就会形成一个单独的磁场
So the wire sets up a separate magnetic field
如果这两个磁场
which runs perpendicular, or at right angles,
垂直或者成直角
to our magnetic field here.
那么这两个磁场就会相互作用
And the result is that the two fields react with each other
线圈就会转动
and our coil rotates.
对吗 明白了吗 露西
OK? Got it, Lucy?
把线圈放上来
So, place our coil over the top.
好了
There we are.
它转得又稳又快
Then it goes round nice and fast.
谢谢
Thank you.
现在 我马上就向你们介绍
Now, in a moment, I'm going to be introducing you
管弦乐团中的第一种机器人
to the first robot in our orchestra,
但在此之前
but just before I do,
我想向你们展示一个
I want to show you a hack that we did
在一种非常常见的机器人上所做的改变
with the most common robot of them all.
你们也许觉得洗衣机不算是机器人
Now, you might not think your washing machine is a robot,
但实际上洗衣机是用
but actually, it's just a collection of motors
电动机来复♥制♥
that replicates the manual work
手洗衣物时的手工动作
of having to wash your clothes by hand.
从本质上来说
On a much more basic level,
它将电能转化为机械能
it turns electricity into movement.
既然电能可以转化为机械能
So if it's possible to turn electricity into movement,
那机械能可以转化为电能吗
can we turn movement into electricity?
几周前 我让安迪用一台旧洗衣机
Well, a few weeks ago, I challenged Andy to build a wind turbine
制♥作♥一个风力涡轮机来发电
and generate electricity using an old washing machine.
这没听起来那么蠢
Now, this isn't as stupid as it sounds.
洗衣机通电后
When you put your power into your washing machine,
就能得到机械能
you get movement.
滚筒会转动
The drum spins.
所以如果让滚筒转动
So if you spin the drum,
是不是就能产生电能呢
surely you can get power out?
安迪 你那儿怎么样了
So, Andy, how did you get on?
还不错
Not too bad, not too bad.
我并没有在这个涡轮机里使用太多零件
I didn't use too many of the bits of the washing machine in the turbine,
你看它们还散落在这儿
as you can see, littered around here.
很显然 主要部分是电动机
The main bit, obviously, is the motor.
这是使洗衣机滚筒转动的主电动机
This is the main motor that turns the drum in the washing machine,
正如你所说
and like you said,
如果我们能使电动机转动
if we can use something else to turn the motor,
那么电动机就应该产生电能
it should generate electricity,
我们要试着使用这些涡轮叶片
so we're going to be trying to use these turbine blades
来启动电动机 尝试发电
to turn the motor to try and generate some electricity.
好的 能产生多少电能呢
OK. How much electricity?
也许不会很多
Maybe not all that much.
这可能不是世界上
This probably isn't the most efficient way
最有效率的发电方式
to generate electricity in the world,
但足可以让这前面的
but we should be able to get some light
这些小灯亮起来
out of these torches on the front here.
-所以我们注意看这些灯就行了吗 -是的
- Right, OK, so it's these we need to keep an eye out, is it? - Yeah.
好的 那我们就来试试看
Right, so, we need to test it.
当然 讲座现场没有足够大的风
Now, of course, it doesn't get that windy in the lecture theatre,
所以为了方便
so Andy, quite conveniently,
安迪带来了鼓风机
has brought his leafblower with him.
这边可能会有点吵
So it might get a bit blustery over here,
大家捂好耳朵哦
so hang on to your heads, everybody.
好了 准备好了吗
OK, so, are we ready?
大家注意看这些灯
So, everybody keep an eye out on those lights.
-开始吧 安迪 -好的
- So, let's test it, Andy. - OK.
就是这样
Right, yeah!
干得漂亮
Fantastic.
叶片转动 灯光产生
The blades are spinning and the lights came on.
我们用洗衣机造了一台风力涡轮机
So we've made a wind turbine from a washing machine.
正如安迪所说 这不是提供电力
Now, as Andy said, it's not the most efficient way
最有效率的方式
to power your home,
却非常好地展示了电能
but it does show that relationship between electricity,
磁能和机械能之间的关系
magnetism and movement really well.
-安迪干得漂亮 谢谢你 -不客气
- Excellent work, Andy. Thank you very much. - You're welcome.
进一步了解电动机之后
Now we know a little bit more about motors,
我们可以开始制♥作♥机器人乐手了
we can start assembling our robot musicians.
我们从简单的鼓开始
So let's start simple, with the drums.
也可能没那么简单
Well, maybe not so simple,
唯一需要考虑的只有节奏
but you only have to worry about the rhythm,
因为鼓的音调是不变的
because on the drums, the pitch doesn't change.
我们只要一台电动机就可以打响鼓
So all we really need is a single motor to play each drum.
比如这面小军鼓
Like this snare drum.
连接每只鼓槌的是电动机
So, attached to each drumstick is a motor
电动机又与电路相连
that will connect the circuit
这样电动机使鼓槌
so that the motor makes the stick hit the drum
不断上下击鼓
and bounce back again.
所以每当我发出指令
So I should be able to just keep hitting that drum
就能击鼓
with every signal.
就像这样
Like so.
击鼓了
And it works.
真棒
Brilliant.
但是只有我一人站在这儿按按钮
But our orchestra isn't going to work
是无法组建管弦乐团的
by me standing here pressing a switch.
所以我们还得将曲子编程
So we need to program that tune.
真正的管弦乐团中使用乐谱
For a human orchestra, we'd use sheet music,
乐谱上有低音部分
which has a line for the bass,
合成器部分及弦乐部分
the synth and the strings
当然还有鼓的部分
and, of course, one for the drums as well.
实际上乐谱和电脑编程比较相似
Sheet music is similar, actually, to a computer program,
它指示乐手该演奏哪个音符
in that it tells the musicians what note to play,
并指示每个音符的演奏时长
how long to hold each note,
及音符的强弱
and how loud they should play it for.
我向你们展示的这台机器人
Now, let me show you a robot
仅根据简简单单的指示
that uses some very simple instructions
就能完成一件很了不起的事儿
to do something very, very cool.
还记得这些吗
Remember these?
有人玩过魔方吗
Has anybody ever tried solving a Rubik's Cube?
不少人啊 你拿着吧 你留着这个魔方吧
Oh, lots of people. There you are, then. You can have that one.
试着把它拼好
Try solving that.
这边的这位 你来拼这个魔方吧
And someone over here, you try solving that one.
恐怕我得留着这个魔方
I need this one, I'm afraid.
现在你们该拼好了吧
OK, now, you should have solved it by now, yes?
你拼得怎么样
How are you getting on?
还没好 还要一会儿吗
No? Not quite?
那行 继续吧
OK, well, keep going.
虽然看上去不太可能
Now, it might seem impossible to solve,
但数学家们表示二十步之内
but mathematicians have shown that you can solve any cube
就能还原任何一个魔方
within just 20 moves...
因为只需一系列有规律的旋转
Because there's a certain pattern of twists and turns
就能还原魔方
that would get the cube back to normal,
即魔方每一面都只有一种颜色
so all of the colours on the side would be the same.
这台机器人的发明者们要挑战自己
Now, the inventors of this robot set themselves a challenge.
这是魔方突击者3
This is CubeStormer 3,
世界上最快的魔方机器人
and it's the quickest cube solver in the world.
你们觉得它要花多长时间才能拼好魔方呢
So how long do you think it will take to solve this?
多长时间
How long?
十或二十秒
10 or 20 seconds.
十或二十秒 好的 还有吗
10 or 20 seconds. Yeah. Any advance?
-三十秒 -十 二十或三十秒
- 30 seconds? - 10, 20, to 30 seconds.