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柔性机械好在哪里?

Why Machines That Bend Are Better

What do this satellite thruster, plastic tool
卫星推进器 塑料制品
and micro mechanical switch have in common?
以及微型机械开关的共同之处是什么呢?
They all contain components that bend
它们都包含可弯曲的组件
so-called compliant mechanisms.
也就是所谓的柔性机械结构
This episode was sponsored by SimpliSafe.
本节目由SimpliSafe赞助
More about them at the end of the show.
更多相关内容在节目末尾
Now about a month ago
大约一个月前
I was giving a talk in Utah hence the suit
我穿着这身西装在犹他州做了一次演讲
and that’s where I met this guy
在那儿我遇见了这个人
Larry Howell, professor of mechanical engineering.
我是机械工程学教授Larry Howell
So it’s always been considered to be bad to have flexibility in your machines.
人们通常认为机器有柔度是不好的
We’ve tried to take that thing that everybody hates, that is trying to avoid
我们怎么才能把大家都讨厌的 都想要避免的柔度
and say how can we use flexibility to our advantage?
变成我们的优势呢?
How can we use that to do cool stuff?
怎样用它做一些有趣的东西呢?
Now Professor Howell literally wrote the book on compliant mechanisms.
Howell教授写了一本有关柔性机械结构的书
That‘s the most cited book.
这本书在界内被引用甚广
But he’s pretty nonchalant about his work.
但他却不想过多介绍他的工作
Just watch how he introduces this mechanism
来看他介绍这款机器吧
he developed to prevent nuclear weapons from going off accidentally
他开发这个机器 本想用于防止核武器意外爆炸
Actually in safing and arming of nuclear weapons.
但却被用来保护和武装核武器
And so if…
-所以 如果 -啥?
Hang on, hang on hang on
等等 打断一下
-What-ing nuclear weapons?
对核武器干嘛?
-Safing and arming -Safing and arming
-保护和武装 -保护和武装
Yeah so if there’s anything in the world
对 无论你在世界的哪个角落
that you want to be safe It’s not going to accidentally go off.
确保核武器不会意外爆炸 才能保障你的安全
I feel like this is, it doesn’t even need to say
我知道这……这不必多说
but yes, nuclear weapons obviously, you don’t want them to go off.
是没错 谁也不想核武器爆炸
What I don’t understand how this is gonna keep the nuclear weapons safe.
但我不明白它要怎样确保核武器的安全性
Now I want to come back to this device and explain how it works
现在我们说回这个装置 解释一下它的工作原理
Once we understand why compliant mechanisms are best suited to this task
首先我们需要了解为什么柔性机械结构最适合这个任务
还挺酷
So let’s start with something basic.
让我们从一些基础开始
Probably the first compliant mechanism I ever designed wasthis thing.
这大概是我设计的第一个柔性部件
What it is is a compliant mechanism that is a gripper.
这个柔性机械其实就是个钳子
So you can put something in there
你可以把东西放在这儿
It will get actually a really high force.
它就会受到很大的力
I can put that in there
我可以把粉笔放进去
and it breaks the chalk
就能轻易把它弄碎
What have you put your finger in there and squeeze it?
如果你把手指放里面然后按下去会发生什么?
You would scream in pain
你会疼得尖叫
Would you like to try?
你想试试吗?
I would like, I would actually like to feel the force
我想试试 我想感受一下这个力道
OK, you need to squeeze it yourself though or it’s… -Really?
-那你得自己按下去 否则…… -真的?
Well all right, I’ll squeeze until you scream in pain
-好吧 你喊疼我就停 -别……
Aaahh hahaha
啊啊啊啊哈哈
That very quickly got incredibly painful.
一下子就变得非常的疼
It felt like having my finger like in a in a vice.
就像我的手指被老虎钳夹住了一样
That looks suspiciously like vice grips.
它看起来像极了老虎钳
but now with these flexible components where the hinges are.
但柔性部件不需要这些铰链
What I learned in my visit with Professor Howell
在拜访Howell教授时我了解到
is that compliant mechanisms have a number of advantages over traditional mechanisms
柔性部件与传统部件相比具有很多优势
But I thought he needed kind of a clever pithy way
但我觉得需要一个聪明简洁的方法
to remember all of these advantages.
来记住所有这些优势
So I came up with the eight pieces of compliant machanisms
于是我列出了八个柔性机械的优点
and the first of those is Part count.
第一个优点是部件数量
Compliant mechanisms have reduced part count
柔性部件减少了部件的数量
because they have these bendy parts
因为它们具有这些易弯曲的部分
instead of having things like hinges and bearings and separate springs.
而不是用像铰链 轴承或单独的弹簧这种东西
This gripper is just a single piece of plastic
这个钳子只用了一块塑料
but achieves a similar result to the much more complicated vice grips.
但达到了一个结构更加复杂的老虎钳的效果
Like how much does it amplify the force?
它能将力量增强多少倍?
This will get about thirty to one
答案是大约30倍
so I could get for one pound force in, get thirty pounds out.
这意味着我施加1磅压力 就会输出30磅压力
That’s pretty good. It seems like that would be super cheap.
-那太棒了 -耶
它看起来应该挺便宜的
And really inexpensive, so this we just made here in our shop
确实不贵 这是我们在自己商店做的
but you can imagine also injection molding that
但是你可以想象我们注模之后
-That would cost like cents -Yep, this would cost cents
-成本只需要几分钱 -对 只要几分钱
The other thing is because of its shape
另一个好处是 由于它的外形特点
you could extrude it and then just chop them off.
你可以把它压制出来 然后切段就可以了
That would be cool.
这就很酷了
So the simple design allows different production processes to be used
由于设计简单 可以用很多不同的方式生产
which lowers the price
这样就降低了成本
These switches, for example, achieve in one piece of plastic
例如这些用一块塑料制成的开关
what is normally done with springs, hinges and many rigid plastic pieces
替代了由弹簧 铰链和许多刚性部分组装成的开关
-also a good fidget device -How long can these last?
-它还是个不错的指尖设备 -这种开关能用多久?
We’ve had these in our fatigue testing machine.
我们将它放在耐久试验机中测试
We’ve been able to go over a million cycles without failure
一百万次循环使用都没损坏
-What have we got there? -All right, Derek I’ve got a quiz, quiz for you.

-这是什么? -好了 Derek 我要考你一个问题
Okay, I’m gonna -elephant!
-那么 我要…… -大象!
Very good!
答对了!
Okay I’m gonna push on elephant’s rump, this direction okay?
那么我把大象的屁股往这个方向推 懂哈?
I’m gonna hold this
我会抓住这个地方
and that little dot right there, is that dot,
这里有个小圆点 这个点
when I push on it,
当我推这里的时候
is it gonna go left, right, up or down?
请问这个它会向左 右 上 下哪个方向移动?
Um…
嗯……
I just, you know what, I wanted to guess without even thinking about it?
那我随便猜了哈?
Yeah, please do.
好 请讲
-I’m gonna say like up and in -okay, up and in
-我觉得会向内向上运动 -好 向内向上运动
And I kind of feel like that because like that would be a logical way
我之所以这么说是因为这比较符合逻辑
for an elephant to hold its trunk -okay
-大象抬起鼻子 -嗯
but also because like, if this is all going over
而且因为 这么推过来
I feel like this is gonna kind of extend there
我觉得这里会延伸到这儿
and that’s gonna get pushed up in there.
鼻子上的点会被推到那里
-Ah, good thinking well -I don’t know, is that good thinking?
-想的不错 -我不知道 刚刚我说对了么?
That’s well it’s thinking at least. So…
还不错 这至少是个想法 嗯……
This is designed so that when you push on that
其实当你推这里的时候
it actually just rotates in space.
它只会原地打转
It doesn’t move at all.
根本不会动
I knew you were gonna pull some sort of trick
我就知道你会设陷阱
it’s a trick question!
这就是个陷阱题!
now since I was fooled by it
既然我被这个问题骗了
I had to try it out on my friend, the physics girl.
我必须也去整整我朋友 那个物理女孩
That’s so trippy.
这太具有迷惑性了
-That is so cool! I don’t understand What!
太酷了!我不明白 怎么会这样!
it’s modeled after the mechanisms you use in wind tunnels
它是根据在风洞中使用的机械建模的
where you want to have, say, a model that’s that’s attached here
当你想把模型固定在这里
but you move it
但要动它
and all you want to do is is control its its angle and move it around in a wind tunnel.
你要做的就控制角度 让它以风洞为中心移动
don’t displace it but be able to change the angle.
不移动它 却可以改变角度
Devices like this demonstrate that
像这样的装置展示出
compliant mechanisms are capable of producing very precise motion
柔性部件能做出精确的动作
which I personally found pretty counterintuitive
这与我个人的直觉恰恰相反
because these objects are made up of flexible parts
因为这些东西都是由柔性部件组成
but maybe that shouldn’t be surprising
但或许也在意料之中
because compliant mechanisms don’t suffer from backlash for one thing.
一方面原因是柔性机械不受反冲影响
So backlash occurs when you have a hinge
铰链会发生反冲
which is basically just a pin in a hole
大体意思是 一根栓插在洞里
and it’s moving in one direction
栓朝向某一方向移动
and now if at some point the motion reverses
然后如果某一时刻栓移动方向突然改变
it doesn’t happen instantaneously
外壳无法立即改变方向
because there’s some give in the hinge.
因为铰链中存在空间
This also causes wear and requires lubricant
这会导致耗损并且需要补充润滑剂
and that is why compliant mechanisms
这就是为什么柔性机械
have better performance than their traditional counterparts.
可以比传统铰链更好地执行动作
This one though is my favorite.
这个是我的最爱
That is is one of my favorites too.
这个也是我的最爱
It’s just so pleasing, right? Ahhh,
它太令人愉悦了 对吧?
that sound is so satisfying.
这个声音听起来太享受了
This actually, believe or not
不管你信不信
was inspired when we were doing things at the microscopic level
其实它是我们在做微观层面的实验时 获得的灵感
where we’re building compliant mechanisms on chips
当时我们正把柔性机械使用在芯片上
We had to be able to make these compliant mechanisms out of silicon,
我们必须能够用硅制造出这些柔性部件
which is as brittle as glass.
硅和玻璃一样易碎
which is as brittle as glass.
你若想不用玻璃 做出一个这样的东西
it’s crazy hard
真的极度困难
But that also means once we figured out the design
但也意味着如果我们搞明白如何设计
we could make it in a material even like PLA
我们甚至能使用像聚乳酸这种材料做它
which is also, you know, not the ideal compliant mechanism material.
你懂的 聚乳酸并不是柔性部件的的理想材料
So you can get on our website
你可以登录我们的网站
and get the material… and get the files to make this yourself
下载相关材料和文件来自己制作
I’ll put a link in the description
我会把链接放到简介中
That also has a nice feel and nice snap to it
它的手感和撞击感很棒
It has a really nice snap. I like when it comes out,
确实很棒 我很喜欢向外拨动它
It’s like“gunk” , you know, there’s something about that that’s really it’s very pleasing.
这手感就像“吧嗒” 真的让人很愉悦
So these things actually move?
它们真的能动?
Oh yeah, yeah yeah
是 对 没错
-I need to see this okay -all right we’ll do it
-我得看看 -好呀 我们来试试
Were those etched on there?
它们是被蚀刻在上面的么?
Yeah, those are etched and so just using the same process as used to make computer chips.
是的 它们用电脑芯片制作技术蚀刻在上面
So another advantage of compliant mechanisms is
所以柔性部件的另一个优势是
that they can be made with significantly smaller proportions
可以被做成很小的规模
because they take advantage of production processes like photo-lithography
因为它们可以利用类似光刻技术的技术
And we have motion that we want at the microscopic level.
嗯 而且我们希望可以让它在微观层次运动
that’s brilliant.
太棒了
Plus, since they simplify design,
此外 自从他们把设计简化后
compliant mechanisms are much more portable, meaning lightweight
柔性机械变得更加轻便 意思就是重量更轻
which makes them perfect for space applications.
这一点特别适合应用于太空
This here is something we did with NASA making a hinge
这个是我们与NASA合作制作的折叶
that can replace bearings for say deploying solar panels.
它可以代替连接太阳能电池板的铰链
This is titanium, 3D printed titanium.
这是钛 3D打印的钛
But what’s freaky about it is
但它不同寻常
you get that motion which people expect
它可以做出人们意料之外的动作
but there’s a piece of titanium that can bend plus minus 90 degrees,
因为它是一块能够左右弯曲90度的钛
180-degree deflection
可以有180度的偏移
That is solid titanium.
它可是一整块固态钛啊
That is one piece of titanium that is 3d printed
一整块3D打印出的钛
-There’s no alloy, nothing to make it flexible. -Yep, this is, yeah
-没有加入合金使它变得易弯曲 -是的 没错
And even freakier than this is this guy right there.
更不同寻常的是这个家伙
So that looks like a crazy beast
它看起来是一团乱麻
but every part in there has a purpose.
但每个部分都有其作用
All these flexible beams, here are the two inputs
这些是柔性梁 这俩是输入端
And again we did this with NASA for a thruster application
它也是我们和NASA合作 用于推进器的组件
where you can put a thruster right there
你可以把推进器放在这里
and now with our two motor inputs
通过这俩马力输入端
we can direct that thruster in any direction.
我们可以让推进器指向任何方向
That titanium device moves that,
这个钛制装置运作的时候
you notice, that’s just all bending
你会发现它们都是弯曲的
and then there’s no pinch points for the fuel lines or electrical lines coming in.
燃料管线和电线不会受到挤压
Here, this single piece of titanium allows you to use one thruster
这样 一块钛就可以作为一整个推进器
in place of two.
无需用两个推进器
Okay, that is a clutch
那是一个离合器

So the idea is if you spin it up really fast
原理就是 如果它转得特别快
because it’s flexible, this outer part will actually start coming outwards
由于它的柔韧性 外部会向外打开
and then if there’s a drum around it
如果它外面包着一个滚筒
it’ll contact with that drum and spin that thing
它会卡住滚筒 然后带动滚筒转动
Oh, so this like kind of, oh!
所以它会 噢!
That kind of comes out, like so
会向外扩张 像这样
When it gets spinning really fast
当它转的足够快
and then you’re essentially engage this outer drum
就会带动外层的滚筒
This is like the way that a chainsaw would work or something like that
这和电锯的原理差不多
because you get it spinning fast enough
因为当电锯足够快时
and it engages the chain and then it turns over
就会卡住链子 带动旋转
-Centrifugal force, Wow, that’s cool
离心力 哇 那太酷了
So here this is made of plastic, you can see it
如你所见 这是塑料做的
But in reality it’s gotta be a lot stiffer
但在实际应用上我们会采用更加坚硬的材料
so here it is made in steel -What?
-这个是用钢做的 -什么?
So hang on, you’re saying that that thing, which is made of steel
等一下 你说它是用钢铁做的
-Yep -You spin it up to a certain speed
-对 -你把它加速到一定程度
and then it expands and engages a drum that is around it
-然后它向外伸展 卡住滚筒 -对
-Yep -So idle with no motion
对 闲置时不会伸展
but then at a certain speed that are what we designed it for
但预先设定一个转速
It will speed up to that rpm
它就会加速到那个速度
-You speed it up and it engages -Yup
-你给它加速 然后它带动其他部件 -对
I had no idea like I have learned something today
我不知道…… 我今天收获良多
So let’s come back to the safing and arming device for nuclear weapons.
让我们回到核武器保护和武装装置这个话题上
Its purpose is to ensure that no random vibrations, say, from an earthquake
它的作用是确保没有任何意外震动 比如地震
inadvertently disable safeties and arm the nuclear weapon
无意中导致安全装置失效引爆核武器
Now one of the requirements was
其中一个要求是
that this device be made as small as possible.
装置要尽可能小
They had made those as small as they possibly could using traditional methods
他们用传统方法尽可能往小做
even using things like what the Swiss watch manufacturers were using.
甚至用上了制造瑞士表的方法
With compliant mechanisms they produced a device out of hardened stainless steel
他们运用柔性部件 用硬化不锈钢制作出了一个装置
where some components were the size of a human hair.
装置的部分部件只有头发丝那么大
This is high-speed video
这是用高速摄像机拍摄到的
Here the device is operating at 72 Hertz
图像中 装置以72赫兹的速度运行
meaning this little hole makes two complete revolutions each second
意味着这个小洞每秒转两圈
The way it’s meant to work is an arming laser shines on the rotor wheel
工作原理是 一束引爆激光射在叶轮上
and when the proper input is given to the system
当相应指令被输入进系统
the wheel rotates a notch.
叶轮会转动一个凹槽
If all the proper inputs are given
如果输入的所有指令都正确
then the hole lines up with the laser beam
这个洞就会跟激光束对齐
and crazy things happen from there.
可怕的事情就会发生了
So it is essential that this device’s performance is perfectly predictable
所以有必要确保 这些装置就算在发射井中放置几十年
even if it sits unused in a silo for decades.
也可以精准预测意外震动
So are these now being used on nuclear weapons?
那么 这些装置现在已经投入使用了么?
You know, it turns out that they don’t tell us what they do with their nuclear weapons
他们不会告诉我们 要用装置对核武器做什么
So we design them, we made prototypes we tested them
我们只是设计出来 做出原型 进行试验
and then it goes what they call behind the fence.
之后的事情就不得而知了
And…where it’s all classified and, you know
这些都是机密的内容
We don’t know what happened, so…
我们不知道后面发生了什么 所以……
Hey this episode was supported by viewers like you on patreon and
嗨 本集是在Patreon的观众的支持下
by SimpliSafe, incredibly effective reliable home security.
和高效可靠的家庭安全系统SimpliSafe的赞助下播出的
Now I started thinking seriously about home security
我开始认真考虑家庭安全的问题
one day when there was this police helicopter circling overhead
因为有天一架警用直升机在我头顶盘旋
and it turned out that the house across the street had been broken into.
只是因为街对面的住宅被人私闯
SimpliSafe makes it easy to protect your home.
SimpliSafe让家庭保护更简单
they sent me a kit including a base station,
他们给我送来一套工具 里面有一个基站
camera
摄像机
and multiple sensors
和许多传感器
And the setup was simple. It only took me about an hour to complete.
安装过程也很简单 我只花了大概一个小时就完成了
The system is monitored by professionals 24/7
该系统由专业管理人员全天候监控
and they can call you or send police in the event of a break-in.
如果有人闯入 他们会给你打电话或者直接报警
So it’s easy and intuitive to use.
所以它非常简单且易于操作
There’s also these thoughtful features that are built-in
同时还内置很多体贴的小功能
for example it reminds you if you left the door open.
比如 如果你出门时忘记关门 它会提醒你
Pricing is fair and honest with no contracts or hidden fees
价格公道合理 没有任何合同以及隐藏费用
and it’s equipped for worst-case scenarios like
而且即使在最坏的情况下
if the Wi-Fi goes down or the power is out it still works.
比如Wi-Fi没信号或者它没电了 仍然能够运作
So to find out more go to SimpliSafe.com/Veritasium
了解更多信息 请访问网址:SimpliSafe.com/Veritasium
I want to thank SimpliSafe for supporting Veritasium
在这里我要感谢SimpliSafe对《Ve元素》的支持
and I want to thank you for watching
同时感谢您的收看

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视频概述

介绍易弯曲的柔性机械各方面的优势和应用。

听录译者

收集自网络

翻译译者

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视频来源

https://www.youtube.com/watch?v=97t7Xj_iBv0

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