Episode 4 Richard Hammond's Miracles of Nature

'Animals are amazing.'

That's astonishing!

'And the more we find out about them, the more amazing they seem.'

That feels pretty harsh!

'That's why scientists all over the world are trying their best

'to copy them.' This is the future!

'Making brand-new inventions...'

Tomato juice.

'..based on what animals can do.

'Some are astounding...'

We've just dived under the sea!

'Some bizarre...' This is not at all pleasant.

BOOM!

Yes! It's gone!

'But they're all inspired by the miracles of nature.'

Episode Four.

How these little flying rodents might revolutionise life

for the visually impaired.

I want you to watch the next 30 seconds very carefully.

In just a few minutes,

a second rider is going to come down this track,

through the same twists and turns,

over the same humps and bumps.

But with one big difference -

this rider is blind.

But how is that possible?

To find out, we need to start with a creature

that spends the majority of its life in permanent darkness.

A creature that can navigate its way around these caves and caverns

without using a head torch.

In fact, without using its eyes at all.

I'm talking about bats, of course,

because we all know that bats can get around in the dark.

But bat expert Dr Dean Waters is about to show me

that their senses are far cleverer than that.

-Have you got one?

-I've got one here.

-This is an Egyptian fruit bat.

-Hello, Egyptian fruit bat.

Beautiful big eyes and they also have these lovely ears that are very, very mobile

that they wiggle around a lot.

And they echolocate through their mouth.

They'll open their mouth and click from side to side with their tongue.

HE CLICKS

-That's it?

-That's it, very simple.

So it's not like a special... It's just their tongue...

Just a click, that's it.

HE CLICKS

But that simple clicking noise bounces off solid objects

and by listening carefully to the echo,

the fruit bat can find its way about.

But just how accurate is it?

Time to put the bat's super sense to the test.

We're using a very hi tech combination

of cup hooks, bells and string

to make a type of bat slalom course.

But we really haven't made it easy for them.

The strings are less than a centimetre wide

and the gaps between them are much narrower

than the bat's two-foot wingspan.

We'll be watching the action using an infrared camera.

The bats will still be in pitch black,

but now, we should be able to see them via Dean's laptop.

OK, then, Dean. Lights out. Let's see what we've got.

We don't have to wait long.

A single bat appears.

And what he does next is remarkable.

Nearly, go on, you're going to go through...

Oh, that's perfect, no, that's absolutely perfect.

That was... He was bringing his wings in,

he knew they were either side, exactly where they were.

By emitting a series of high-pitched clicks

then listening for echoes bouncing off objects in front of them,

the bats are picking up even these narrow strings.

And by pulling their wings in at exactly the right moment,

they just sail through.

So if a bat can use sound,

a series of small clicks, to see in the dark,

maybe it could work for human beings.

This man, Professor Brian Hoyle,

believes he's found a way to do just that,

by putting bat-tech in a stick.

So, this isn't just a bit like the way a bat works.

This is echolocating.

-It is very, very similar indeed. Over to you.

-Right, it's beeping at me!

-That was you!

-It was me.

-It's found you! Look at that!

And if I move it off, it stops.

I'm going to go behind you, so I can see what's going on.

I felt you walk through.

So, what I'm doing now, this is sending out a noise,

the same as a bat does, and then listening for it bouncing back,

echoing back off objects, which is exactly what our bats did.

-It then tells me, by buzzing, on this.

-Absolutely.

And you can feel it. So if I walk towards that...

-Ooh, it's found something.

-Just take it slowly.

-It's buzzing through my thumb.

-Good.

-If I move off, it's not.

-Great.

So, it's telling me there's an object to my left.

You found a safe path to the right.

Bring on the blindfold.

Let's give this a proper go.

Right, let's see if I can pick up in a matter of minutes

what it's taken the fruit bat millions of years to perfect.

Nothing - oh! Something to my right.

Hang on, there's a gap there.

I've got something to my left, there. And to my right, there.

Picked up something, then.

Oh, that's a mannequin, isn't it?

Slowly but surely, I can see how somebody could build up a picture.

Right, the only thing is, I have no idea where I've ended up.

Right, I had no idea that I was here.

Well, I think you did really well,

and I don't think you bumped into anything.

I didn't hit anything.

So I thought, what if we take this whole idea a step further,

and use bat sonar to enable blind people to do something

they wouldn't normally even attempt.

So I've taken apart a couple of canes,

and I've come up with this, the Bat Bike.

Now, let me talk you through this.

Essentially, it's a prototype at the moment, but it shows the principle.

We've got two Bat Cane handles up here on the bars,

with the contact pads, feeding back information to the rider from

the sensors in the handles themselves,

then we've got two more down here.

I reckon that should be enough information feeding back

to the rider to enable a blind person to ride

a mountain bike down a mountain bike course.

Now I say it out loud, that is quite a big ask, but it could work.

By the time engineers have built our Bat Bike properly

a few of the details have changed, but the theory remains the same.

These sensors send out and receive a series of clicks

and a couple of vibrating buttons tell the rider what's up ahead.

That rider is 21-year-old Dan Smith.

A keen cyclist, Dan tragically lost his sight nine months ago

from a rare genetic condition.

He hasn't been able to ride a bike on his own since.

Although most of the damage to his eyes is invisible, trust me,

Dan can't see anything in front of him.

Five, four, three, two, one, go!

HEART BEATS

My heart's in my mouth, but Dan sets off brilliantly.

BAT BIKE BEEPS

Dan only had a few short hours to practise on this bike...

..but bat technology is allowing his brain to see the course.

So how did Dan find it?

Yeah, very good, actually.

The technology works, because I've just navigated

the whole track by myself, so I'm very pleased, yeah.

Well, there could be no clearer proof that bat-tech works.

It's just another example of the miracles of nature.