节目资讯
刊物:空中英语教室
日期:2013-05-22
难易度:High
关键字:precisely, nozzle, mature, hearing aid, prototype
We're talking about 3-D printing today.
Of course you don't need to go to a factory to get some things done, to get some
things printed.
You could print objects that you could see and hold and use.
Of course usually when you think of printing, you think of 2-D objects printed
out on a piece of paper.
Now you can have 3-D printing.
And this, of course, uses some plastic in a special 3-D printer.
We're going to be learning a little bit more about this in the rest of today's
lesson.
(Music).
3-D Printing: No Factory Required!
3-D printing: then and now.
3-D printing technology first appeared in the 1980s.
At that time, it was used as an inexpensive way for companies to make prototypes
before creating final products.
But 3-D printing technology has matured to the point where printers can now
create high-quality objects using a variety of materials, including metals.
That means 3-D printers can now make final products that meet high industrial
standards.
3-D printers are already being used to make parts for racecars and jets as well
as artificial limbs and hearing aids.
(Music).
It sounds like 3-D printers will be very, very useful.
And at the beginning of this section we see the title: 3-D printing: then and
now.
So we're going to get a little information on the history of 3-D printing and
how it's changed.
How does this begin, Gabe?
Well, yes. If you're talking about then, or saying the phrase "then and now,"
usually "then" means in the past.
So then, or back then, and now.
Our first sentence is:
3-D printing technology first appeared in the 1980s.
It first appeared at this time.
What does that mean, Carolyn?
Well, when something first appears, then that's when it was first used or even
invented.
So people were using 3-D printers for the first time in the 1980s.
And we see at that time, it was used as an inexpensive way for companies to make
prototypes before creating final projects.
And a prototype is the first version of something so you can get an idea of what
it will look like or how it will work,
and maybe some problems that you might face in the future and changes you can
make.
That's right.
Sometimes you're not satisfied with the prototype, but that's why a prototype is
important.
And so if you wanted inexpensive way to create something, well, some people used
3-D printing before creating the final products.
Let's continue.
But 3-D printing technology has matured to the point where printers...
What can they do?
They can now create high-quality objects using a variety of materials, including
metals.
All right.
So they have matured to this point.
Let's take a look at the word from the Word Bank.
It is "mature." Carolyn, I usually think of humans, people, they mature over
time.
We get more and more mature hopefully.
Uh, but how is this word used in our lesson?
Well, here it's describing how the process has developed.
So printers have gone from being something that was used to create a prototype,
or these 3-D printers were used to create prototypes, and now they have changed.
They have developed or matured into something else.
They can now create high-quality objects, not just a cheap prototype but
something you could actually use.
That's right.
And we see this phrase: they've returned to the point of something.
That's another great phrase to know: to the point.
You could use this phrase like this.
The... the turkey was cooked to the point of burning.
They burned the turkey.
How else might you use that phrase?
Well, I think that people have become very intelligent, and they've come up with
all of these new inventions.
And actually, we've gotten to the point where we can fly around the world in a
very short time.
It's true.
So these are great ways to use that phrase.
Well, let's continue.
This means... or that means that 3-D printers can now make final products that
meet high industrial standards.
Well, it's time for us to take a look at a special video.
Let's do that now.
So maybe you've heard about the MakerBot Replicator 2 Desktop 3-D Printer, but
you don't know how it works.
It's cool.
I'm Bre Pettis, CEO of MakerBot, and I'm going to walk you through the MakerBot
creation process.
The MakerBot Replicator 2 Desktop 3-D Printer is the easiest, fastest and most
affordable tool for making professional quality models.
If you're an engineer, or an engineer at heart,
you can keep a MakerBot Replicator 2 Desktop 3-D Printer right on your desktop
and produce amazing high-quality models while you work.
The MakerBot creation process starts with a digital design.
This can be a design that you create using any digital modeling program.
Or you can download one of thousands of models from our site, Thingiverse.com.
Thingiverse is a community forum where people, like you, can share their digital
designs.
There are over 25,000 things on Thingiverse.
And most of them can be made on the MakerBot Replicator 2 Desktop 3-D Printer.
And the best part - they're all free.
Once you got your digital design, the next step is to open it in MakerBot
MakerWare.
This is the software that allows you to prepare your model to be made on your
MakerBot Replicator 2.
MakerBot MakerWare is a brand new software tool developed right here at
MakerBot.
You can use MakerBot MakerWare to move and scale your model, and to arrange it
just so on the virtual build plate.
When you got it just how you want it, just press Make It,
and the MakerBot Replicator 2 Desktop 3-D Printer will begin transforming your
digital 3-D model into a physical 3-D model.
The material that the MakerBot Replicator 2 Desktop 3-D Printer uses is a
renewable bio-plastic called PLA.
When you tell the MakerBot Replicator 2 to make something, it begins by pulling
the PLA filament that's spooled in the back up through this tube and into the
extruder.
The extruder heats it up and squishes it through a very small hole on to the
build plate.
It starts by laying down the bottom layer of your 3-D model.
Then the platform moves the object down a tiny bit so the extruder can lay down
the second layer.
The process continues for the next layer, and the next layer, and the next
layer.
This process can take some time because each layer can be as fine as 100
microns.
When you're done, you'll have a professional quality model that doesn't require
any sanding or finishing.
Now you know how a MakerBot Replicator 2 Desktop 3-D Printer works.
And it's time to set your mind in motion thinking about how you're going to use
yours and what you're going to make.
Well, 3-D printers can be used for so many amazing things.
And we see 3-D printers are already being used to make parts for racecars and
jets as well as artificial limbs and hearing aids.
Hearing aids?
Wait. Can you say that again?
Well, yes, we're going to say that again - hearing aids.
Well, let's take a look at that.
It's from our Word Bank.
Do you have hearing aids?
Or do you use hearing aids?
Some people do.
They put them inside their ears.
And then it can help them hear things a little more clearly.
You can put in the hearing aid or... or take out your hearing aid.
Well, it would be very interesting to be able to print a hearing aid or even an
artificial limb,
a part of your body that isn't a real part but maybe made of plastic or metal.
Well, now it's time for us to spend some time with Michelle in the Language Lab.
(Chinese).
And let's head back to our teachers now.
3-D printing is a very interesting topic and can be used to do so many things.
You can print hearing aids, artificial limbs or parts of race cars and jets.
It's all very impressive.
Gabe, what do you think is the most interesting thing we've learned so far about
3-D printers?
Well, actually if you have your magazine, on page 39 there are a couple other
interesting facts about 3-D printing.
Jay Leno, the TV host, has used 3-D printing to make some parts for his cars.
That is really interesting.
That is pretty amazing.
Well, we have a lot more to learn about 3-D printing tomorrow right here on
Studio Classroom.
So we'll see you then.