Engineers are turning to origami for inspiration
for all types of applications
from medical devices to space applications
and even stopping bullets.
But why is it that this ancient art of paper folding
is so useful for modern engineering?
Origami, literally “folding paper”,
dates back at least 400 years in Japan.
But the number of designs was limited.
There were only a handful of patterns,
maybe 100, 200 total in Japan.
Nowadays there are tens of thousands that have been documented
and most of that change happened in the 20th century.
There were a handful of Japanese origami masters.
And by far the most successful of them
was a man named Akira Yoshizawa
who created thousands of new designs and
wrote many many books of his works.
And his work inspired a worldwide renaissance of origami creativity.
Well, I wanted to fold a cactus.
The first thing one needed to do
is figure out how do I get spines on a cactus.
So you can imagine if I can make two spines here,
I could do the same thing to make a whole row,
then I can go back and do a complete design.
-That’s, what this is. -Wow!
– [Laughter] -And.
And this is actually the cactus and the pot
are from a single sheet of paper.
Paper’s green on one side, red on the other.
-That whole thing is a single sheet of paper. -So this is… this is…
One uncut square of paper.
-How big was that piece of paper? -And this is about a one meter square.
So there is a huge amount of size reduction to
go from a meter down to here.
But you need that to get all of the spines.
-And how long did that take to make? -That took about seven years from start to finish.
-Wow! Why is origami this thing that
was created for aesthetics mainly…
Why is it so useful?
I guess is the question for,
for like, you know, structural things or
比如 你知道的 结构之类 或者
for mechanical engineering or for space applications.
Like, why does it find itself in so many of these applications?
Why is it so useful?
Well, the thing that makes origami useful
is it is a way of transforming a flat sheet
into some other shape with relatively little processing.
This is a folded pattern.
It’s called a triangulated cylinder.
It is bi-stable, meaning it’s stable in two positions.
This is one and then if i give it a twist.
This is the other.
This really has a bunch of bi-stable mechanisms in it
because I can…
You can see how it sort of pops into place.
But if you combine the two mechanisms
going in different directions.
-Then you get the sort of magical color change effect.
-Yeah that’s impressive. So you look at this
and you say: okay that is a cute paper toy.
Is it anything more than that? and the answer is yes.
– Does that turn into that? -That turns into that, yep.
-是刚才的玩具变成这样了吗？ -是的 是它变成这样了
We’re working with a company
called Intuitive Surgical that does the Da Vinci surgical robot
where they wanted to be able to insert
a flexible catheter with the robot.
But the flexible catheters tend to buckle and stuff.
So we had developed these origami bellows
that if you look down there,
there’s a hole that no matter how far we move this
that stays the same size on the inside.
And what that means is we could put the catheter in there.
And as the catheter moves and it’s getting inserted into the body.
It still has supports along the way,
or for another example.
Here I have a foldable bulletproof collapsible wall.
It’s based on the Yoshimura crease pattern.
and if I made this out of a bulletproof material
it could be very compact in a police officer’s car
and deploy out and be bulletproof.
But would it actually work?
Well, they’ve put it to the test.
[The sound of a handgun]
Using 12 layers of kevlar, it can
stop bullets from a handgun.
And a new design featuring interchangeable panels
should be able to stop rifle rounds.
Those in that vial that is, those are actually
bullets that have been stopped by origami.
An intrinsic benefit of origami is that
the simple act of folding a material can
make it more rigid.
– I was gonna ask you about this. -Yeah.
-But I was going to say it’s a way of
making the cans stronger without actually like thinner metal, right?
But for engineering applications the more common challenge
is how to fold thick, rigid materials.
This is… uh… polypropylene.
Okay, very rigid.
There’s no way that I’m going to be able to
fold that into this vertex.
So this is an example that shows a couple things,
surrogate folds, we can use to replace the the creases
and then also that piece of polypropylene folds up,
and it also accommodates the thickness.
By cutting or scoring materials and adding hinges as necessary,
thick rigid materials can in effect be folded.
This is useful for example in deploying solar panels.
This pattern is perhaps the granddaddy
of deployable structures, it’s called the Miura Ori.
It’s been used for solar arrays.
In fact, it was one of the first patterns
that flew on a space mission back in 1995.
It was called the space flyer mission.
As you see here,
it all opens and closes in a single motion
and when it flattens, it’s very thin and compact.
It’s a fun pattern called the origami flasher and
get this kind of interesting flasher motion.
This has been proposed as a design for satellite solar arrays
increasing compactness for launch
and reliability in deployment.
A new area for origami research is
in improving the aerodynamics of freight locomotives.
The thing with freight locomotives is
you know they’re just like bricks going down the tracks.
So their aerodynamics are horrible.
Ideally you’d like to have a nose cone
on the front of a freight locomotive
to improve the aerodynamics.
But you can’t because they’re like lego blocks,
they’re hooked up anywhere along the train.
You don’t know if it’s the first one or the second one or the third one.
Here’s a scaled prototype
showing a pattern that we demonstrated on a freight locomotive.
It folds up to be very flat but then deploys out.
And it turns out our computer models and wind tunnel testing
show that this will save this one company
multiple millions of dollars a year in diesel.
This is a violinist.
It was one of my favorite mechanism designs,
because he fiddles if you pull his head.
Functional motions of origami are inspiring new designs for devices
like compliant mechanisms that can complete full 360 degree rotations,
unlike a traditional mechanisms with you know bearings or hinges.
I can hook on a motor and I can get continuous revolution.
I couldn’t do that with a compliant mechanism.
But it turns out no one bothered to tell the paper folders that and created a
但事实上 不用费心告诉折纸艺人 他们就创造了一种
[The sound of paper]
uh continuously revolving compliant mechanism
which is called a Kaleidocycle.
Origami motions are also being used in medical devices.
These would be you know the creases in the paper.
Uh and we have here now uh forceps.
And so what’s nice about this is
we could put this at a smaller scale right on the medical instrument
to go into the body.
But then can morph and become the gripper
so it’ll be very small incision,
but then go and do some more complex tasks inside the body.
A variant of this mini gripper is now being used in robotic surgeries
replacing the previous mechanism and reducing the number of parts by 75 percent.
The origami inspired device is smaller but with a wider range of motion
and functional origami can be miniaturized even further.
This is the world’s smallest origami flapping bird.
That sounds cool.
This one was devoted to developing techniques to make
microscopic, self-folding origami.
And what you see here is a microscope photo of the finished bird.
But what the bird actually looks like.
-Well. -I’ll need my micro lens.
You’ll probably need not just your micro lens.
You’ll need your microscope
because it’s smaller than a grain of salt.
So it started out, it was a bit less than a millimeter square.
But when it’s folded,
it’s much much smaller. -Wow!
Now you might ask yourself what would anyone ever use
a microscopic flapping bird for?
And the answer is well nothing for a flapping bird.
But there are medical devices, medical applications implants
that are microscopic where you might want a little machine.
This is a nano injector
used in gene therapy to deliver DNA to cells.
It’s only four micrometers thick.
So 400 of them can fit onto a one centimeter wide computer chip.
-There’s some things down there that kind of look a bit star wars to me -Yes.
-在我看来 那儿的东西有点像星球大战 -是的
This art called elliptic infinity
and we wanted to do that in a material other than paper.
You see this from flat
into that elliptic infinity shape.
This is actually a lamp
that’s made from a single sheet,
so it comes in an envelope like this.
Put its cable in.
Add a clip.
Now this relies on a lot of math.
The curvature of these lines affects links
the bending and curvature here, to here, to here.
All of these are coupled.
Pretty much the only way to design them
is by following mathematical methods
and get all the folds to play together.
My professional background is
mathematics and physics.
I did laser physics for 15 years as a profession.
I got my PhD in Applied Physics
and my kind of my job in many cases was
to figure out how to describe lasers mathematically.
And if I could put
my problem into mathematical language,
then I could rely on the tools of mathematics to
solve those problems and to accomplish the goals.
But I also felt like
origami would be amenable to that same approach.
So I started trying to figure out how to describe
origami using the tools of mathematics, and that worked.
I’m sort of fascinated about the math here like
it’s hard for me to conceive of like, what does that math look like?
The math comes down
to a way of representing a design called crease pattern.
-Let me grab a couple of crease patterns. -Okay.
So this is an origami crease pattern.
It’s a plan for how to fold.
In this case, how to fold a scorpion.
A really good way of designing something like this
is to represent every feature claw, leg, tail
by a circular region, a circular shape.
代表爪子 腿 尾巴这样的特征
It’s not circular folds.
It’s an abstract…
It’s an abstract concept that you represent the pattern by a circle,
but then you find an arrangement of those circles on the square
like packing balls into a box.
So for the scorpion you’ve got a long tail.
所以 蝎子 它有的一条长长的尾巴
Imagine a big circle,
like a big tin can,
and the legs are smaller circles, or circles of different sizes.
So you’ve got different smaller cans.
The claws are a couple more circles
and you’re going to put them into a square box
in such a way that they all fit.
So you pack the circles into the box and
the arrangement of those circles
tells you the the skeleton of the crease pattern.
And from that you can geometrically construct all the crease patterns.
You follow rules:
put a line between the center of every pair of circles,
um and then whenever any two lines meet in a v,
you add a fold halfway in between, it’s called a ridge fold,
and there’s similar, more complicated rules
for adding more and more lines.
But the thing is, it’s all step by step.
It says if you find this geometric pattern, that tells you
where to add the next line and you go through that process
until you’ve constructed all the lines.
And when you’re done you can take away the circles,
they were the scaffolding for your pattern,
and the pattern of lines that’s left,
are the folds you need to create the shape,
and that’s what’s shown here.
And this was probably the biggest revolution
in the world of origami design.
Was if you followed that systematic process,
the fold pattern would give you the exact shape
that you set out to fold to begin with.
The circle packing method that I described, this works for anything
that can be represented,
as a stick figure like a scorpion,
you could draw this as a stick figure
with a line for the body and tail,
lines for each of the legs, lines for the claws
And from stick figure, from any stick figure,
you can use circle packing and get a shape that folds it.
But suppose the thing you’re folding is not a stick figure,
suppose it’s something that’s more like a surface,
like a sphere or you know or a cloud
or just in animal terms, a big blobby body like an elephant.
Stick figure algorithm is not going to work,
but there are other algorithms for that.
About 10 years ago, a Japanese mathematician,
named Tomohiro Tachi, developed an algorithm that works for any surface.
You give it a triangulated surface
as a mathematical description,
and he will give you, or his algorithm will give you the folding pattern
that folds into that surface.
It’s now quite famous and it’s called origamizer.
And that is a way you could make
a sheet of anything and take on any three-dimensional shape.
So origami is useful in engineering
because it provides a method of taking a flat sheet of material,
and forming it into virtually any shape by folding
or if the end product is flat,
origami offers a way to reduce its dimensions while still deploying easily.
The simple act of folding can increase rigidity
or origami can take advantage of the flexibility of materials
to create specific motions.
And its principles are scalable, enabling the miniaturization of devices.
Perhaps most of all, origami allows engineers
to piggyback on the bright ideas people have had
over the centuries while experimenting with folding paper.
But translating these ideas into practical solutions
requires a lot of math, modeling and experimentation.