Original subtitles

[narrator] On this episode of How Tech Works.

We go to a lab in Florida,

that sets fire to houses...

on purpose.

And, will 3D technology of the future,

help to unlock the mysteries of the past?

We'll travel to Stonehenge, to find out.

[electronic music]

[show intro begins]

Hello there, and welcome to How Tech Works,

the show that takes you behind the scenes,

up close and personal,

and sometimes just over the top,

on the latest technology stories.

from around the world.

I'm Basil Singer.

Today we'll meet inventors,

who want to put you,

in the driver seat of their personal submersible.

But first,

for centuries Stonehenge has managed to keep its secrets.

But that hasn't stopped researchers

from trying to crack it's many codes.

Now some archaeologists in Britain,

are taking things in a whole new direction and dimension.

Five thousand years after

the mysterious emergence of Stonehenge,

a technique called Photogrammetry,

which uses laser beams and high tech photography,

is going to bring some of that blurry mystery, into fine focus.

We're using a very accurate laser scanner,

which fires a beam of laser light,

at the stones or at the ground's surface,

and measures the time it takes to come back with a reflection.

And that gives us a distance,

by knowing where we are in 3D space.

[narrator] It's one of the only scanners in England,

which captures data, with ½ millimeter resolution.

And when it's finished,

the 3D models will be the most comprehensive ever seen.

It's actually going to be an immense mine for information,

which can be used in all sorts of different ways.

It can be used to monitor the condition

of the monument itself.

It can be used to do research, to do analysis,

on the material to get to parts we can't normally see,

or light it in different ways.

[narrator] For thousands of years,

these 400 ton monuments,

have been silent witness to mysterious rituals.

They've served as a guestbook,

inscribed with some famous names,

including one very famous architect.

What we have here is what is purported to be,

the graffiti left by Sir Christopher Wren,

who's family actually had a home not far from here,

and he's known to have visited here.

And you have the cross for Christopher,

and then the W and then the r- e -n.”

The answers to big questions like,

'Who brought them here?’ and ‘Why?’,

have produced some intriguing theories,

but nothing ‘written in stone’.

Yes, Stonehenge attracts theories,

some of which are very sensible,

some of which are more extreme shall we say.

Basically it's a place of celebration.

It's a long lived place.

It was in use for 1½ thousand years, 1500 years.

It was a place for celebration,

it was certainly associated with the solstices.

The summer and the winter solstices and change of seasons.

But what actually went on here and how they used it,

that's a mystery to us still.

[narrator] Today they're going to scan the last

of the two meter high megaliths.

So at the minute it's basically taking,

a series of overlapping photographs,

which will create a 360 mosaic,

which will be used to colorize the laser scan later on.

[narrator] One crucial aspect of the stones,

is out of reach of laser beams.

The top parts, or Lintels.

So we've got the scans at the sides of the stones,

and like I said that goes up to the kind of top edge.

So what I'm doing is capturing angles shots,

down onto the edge on the top and the sides.

So that when I generate the 3D computer model on the top,

we've got some overlap so that we can register,

the work I'm doing to the laser scanning.

[narrator] Cory Hope sets up a 12 meter jib,

and a stereoscopic camera,

that can be positioned above the stones.

Photogrammetry is better at capturing texture,

color, and those kind of things.

So what we're actually doing here,

is we're combining the two.

And a term that's kicking around is called “lidar” grammetry,

where you are combining the laser survey,

with high quality stereo photography,

to drape over it so you get a truly photo-realistic 3D model.

[narrator] The combination of the two methods,

produces a huge amount of intricate

and finally detailed data.

Each physical stone had roughly about 30 million triangles,

needed to be processed to create the model.

And then over the process of the survey,

that we undertook over a three week duration.

Were up to almost five terabytes of data.

Which is quite difficult to manipulate.

[narrator] Those 30 million triangles,

result in this incredible 3D imagery of Stonehenge,

never before seen.

Now every angle, from top to bottom,

can be scrutinized and studied.

A dream come true for an archaeologist.

We haven't studied all of the data yet.

I say we've only just scratched the surface.

We've only looked at some of the areas we know,

there are carvings on

to look at them to see what the level of resolution is.

It's going to take years of study,

to be able to look at all the stones in detail,

and say whether or not we've got new prehistoric carvings,

or that sort of thing on it.

[narrator] Dave can already look closer than ever before,

at graffiti that has fascinated him for decades.

This is a very good example of the modern graffiti,

that the laser scanning will begin to show us.

This one shows very clearly in the light we got this morning,

but you can see it's a Mr. Bridger who was here in 1866,

he comes from Chichester,

this is an abbreviation for Chichester,

and he's in Sussex.

And he's even put the nice line underneath it.

[narrator] In time the 3D model could tell us more about,

Mr. Bridger’s visit to Stonehenge.

And good news for those of us ‘armchair archaeologists’.

3D virtual Stonehenge,

will eventually be made available online.

Now from the mysteries of the past,

to the mysteries of the deep,

as in ‘Deep-sea diving’,

something for the Jacques Cousteau in all of us.

The Dutch company in this next story builds personal subs.

I know right? Pretty cool.

And so naturally,

How Tech Works, is right there,

on the scene, for a test dive... in a car park.

[upbeat music]

[narrator] This is U-Boat Worx.

It's a company that makes personal submersibles,

for two to five people, with big acrylic bubbles,

that give spectacular views under the sea.

It is a very unique feeling to drive in one of the submarines.

You get a freedom that you have never experienced before.

The pressure hull keeps you at a comfortable one-atmosphere,

all the time so you don't feel any pressure on your ears.

It's a very safe feeling to be underwater.

And today we are doing some very important tests,

with our latest C-Explorer 2 submersible.

[narrator] The C-Explorer 2 is the 10th sub the company's made.

It's designed to go down to 180 meters.

Before they test it in the ocean,

they have to test it out here, in a tank.

Our test results will basically determine,

if the sub is stable enough,

to handle extremely rough sea conditions.

If we are successful today,

we can continue with our extensive test program,

otherwise it is back to the drawing board,

for a costly redesign.

In the C-Explorer submarines,

we really try to give people an excessive amount of view.

Of course they go underwater in the end to see something,

so we build a huge acrylic sphere,

in which the people can sit and this also defines,

or determines the entire model,

and the construction of the submarine.

To give it stability,

we have a pontoon-like structure around these acrylic spheres.

And these will provide ride stability,

and the right clearance from the surface,

for people to get out and in safely.

Let's start with the stability test?

[narrator] Camiel Brants is the lead engineer and pilot.

Michel Hell is his technician.

Before they unbalance the sub,

So I use this for the horizontal position?

they take measurements when the sub is level in the water.

Let's put on the weights.

Okay, I go on the front to put on 150 kilograms.

[narrator] Technician Marcus Bloem,

adds lead weights to the bow,

to make the sub tilt to the front.

150 kilos doesn't sound like much,

but the engineers can add more to a computer model,

to make sure the sub can survive even larger forces.

The sub is tilting forward, exactly the way they planned it.

[man] Two-point-three, okay.

[narrator] The goal is to make a sub,

that's safe and easy for anyone to operate.

So there'll be easy cruising for the wealthy yacht owner,

who ordered this particular sub.

[Marcus] It's really interesting for them to have a submarine,

on their yacht so that they can explore,

to see what's below the surface,

instead of only to see what's on top of the surface.

[narrator] Next they put a 100 kilos on the side of the sub.

To simulate people standing on it.

For example, if you have a canoe, it's small,

if you hang too much to the side it will tip over.

With this boat we want to make sure that,

water can never go into the submersible,

even if there are standing 10 people on the side.

[radio-com] We've got a 100 kilograms on the starboard side.

So you can do your weight measurements.

[narrator] The sub is listing,

but no more than they expected.

It passes the stability test. Now it's time for the dive.

Even though the test tank is less than three meters deep,

[radio-com] Oxygen is running.

[narrator] They run through the checklist,

just like they're going way down.

Opening vents.

[narrator] To submerge the C-Explorer 2,

the pilot opens up valves,

that let out air,

contained in four expandable rubber tanks.

That makes the sub less buoyant.

To bring it back up,

air is pumped back into the rubber tanks.

They expand, and the submarine is buoyant.

Even though the test tank is no bigger,

than two shipping containers,

Camiel and Michel are having fun.

We need to put some small sharks in here or some sucker fish!

to topside, go a bit to the back please for a good position.

[narrator] Camiel works the thrusters,

to move the sub away from the tank wall.

to topside, you have permission to blow your diving tanks.

[narrator] The sub's systems are working well.

[radio-com] I would like to do another dive,

if that is possible?

You have permission to open your vents again.

[narrator] It's time to test the emergency gear.

Okay we are starting procedure to release the buoy.

In case the submarine might get into trouble underwater.

The pilot might decide to release this buoy,

so that it goes to the surface,

and people there can see where the submarine is.

[radio-com] And the buoy has released.

[narrator] The C-Explorer 2,

is designed to bob up to the surface,

if there is a problem.

But if that doesn't happen,

the pilot can release the drop weight.

A 100 kilos of lead. So the sub rises.

[radio-com] Alright we will start procedure,

dropping drop weight.

[narrator] It happens fast.

[radio-com] And it has dropped. Really nice.

[narrator] This dive went well, but many more need to be done.

[Marcus] This C-Explorer, it is destined to go through

a much more extensive test program,

that will be done under the supervision,

of an external classification authority.

Once it is completely certified,

it will be delivered and commissioned,

together with the end user.

[narrator] As to the cost,

U-Boat Worx Subs start at around 600,000£.

With a price tag like that, the view has to be priceless.

Do not go away.

We'll be right back with lot's more, How Tech Works.

[intro music]

Welcome back to How Tech Works.

I’m Basil Singer,

and now we're off to a lab in Florida,

who do something, totally crazy.

Because they set fire to houses, on purpose.

I know!

I want to go there and checkout their latest in fire prevention.

We call it, ‘Burning the house down'.

[intro music]

[narrator] This is a place where people,

love to set things on fire.

I will admit to being a bit of a pyro.

[narrator] Today Julie Rochman,

is setting a whole house on fire.

We are actually making for the first time,

anywhere in the world,

indoors, in a controlled environment ember storms.

[narrator] It's all being done in the name of safety.

At this one of a kind facility in Tampa, Florida.

The IBHs research center was created for the single purpose,

of trying to identify, evaluate and promote effective ways,

to reduce property losses,

from a variety of natural disasters including wildfire.

[narrator] Wildfires are becoming more,

and more of a problem.

[Julie] In 2011 we saw record wildfire losses,

throughout the south west.

At one point this Spring,

Texas was on fire from border to border.

There was a wildfire in virtually every county.

At this point in the United States,

one out of three housing units,

is actually located where the brush and the trees,

meet development.

[narrator] Advancing walls of fire can cause damage.

But they're not the only threat.

The problem when it comes to property protection,

are the embers or the fire brands that travel on the wind,

a mile or more beyond the perimeter,

that the fire services have set up.

Those embers will find something to ignite,

on or near or inside a home,

and those homes will then burn,

because there is nobody there to protect them.

[narrator] Julie and her team,

want to learn how to protect homes from these embers.

The best way to do that?

Burn one down!

But before you can burn it,

you have to build it. And it is no doll house.

The IBHS research center,

is the only facility of its kind on the planet.

We are the only place where you can do,

full scale one and two story building specimens,

up to about 2000 square feet.

On which we hang different types of siding and roofing,

and gutter materials.

Windows are installed, we put mulch and vegetation,

around the specimen so it is not finished on the inside,

because we are really looking at exterior ignition points.

[narrator] To ignite the fire here,

chief engineer Tim Reinhold,

is burning mulch and dowels in a chamber.

The biggest challenge was in generating the embers,

and getting the system to work where we had a good dispersion,

of the embers coming in at the houses.

[narrator] 105 fans will blow hot sparks at the house.

[Tim] A fan blows those embers up through ducts,

and release it into the wind stream,

from there the wind,

carries the embers and they attack the building,

the way the embers would in real world.

where they are ducted around the building,

and the swirling motion of the wind.

Typically the most dangerous wildfires,

are the ones that occur when you’ve got,

a fairly strong wind environment,

blowing the embers.

Sometimes over complexed ranged 70 or 80 miles an hour.

And those are the ones that the fronts move like crazy.

[narrator] Everyone’s watching where the embers will go.

[Julie] What we hope to learn,

is exactly how different sizes and types of embers catch,

so the smaller embers,

that tend to be blown or drawn into openings,

like soffits or gable end vents,

or the larger embers that will sit on the top,

of an untreated wood shake roof,

and burn unnoticed until they actually fall through,

the layers of shake,

into the home and burn it from the inside out.

[narrator] Today they are getting some answers.

[Tim] One of the myths that was out there,

was that you should leave one window open for the fire dept.

to have access to your house.

You don’t want to do that.

If a flame gets up there a screen is going to melt,

in a heart beat,

and now you've got a pathway,

for the embers to come right into your house.

It's very important to seal up,

keep things out as much as you possibly can.

[narrator] Getting this kind of information,

is exactly what makes this facility,

and these kinds of tests important.

When you break things you learn a lot.

You learn a lot more from destroying things,

than you do from when they work well.

[narrator] This is just the beginning.

They plan to do lots more tests in the future.

For Julie it makes being a pyro all worthwhile.

Everything that we do here,

is designed to help home and business owners,

better protect their property.

We want to teach people how to demand better construction.

How to get safer construction,

and how to reduce losses so we don’t see injuries and deaths,

and property destruction as a result of wildfire,

and other natural disasters.

Finally, when it comes to high-tech toys,

this next gadget is just, wicked.

It's a pulse jet bike, powered by,

you got it, the jet from an airplane.

I'm not sure if it comes with training wheels,

but we warn you, it might get loud.

[narrator] The sound will take your breath away.

[motor blaring]

It sounds like a 1000 sledgehammers,

pounding on a rail-road track.

It's not good, but it's interesting.

[upbeat music]

-[narrator] Bob Maddox likes interesting.

He took a simple schematic of a V1 bomb,

from The Second World War,

[buzzing noise]

and he turned it into, locomotion with attitude.

This time it's a bomb strapped to a bicycle.

Well no, it's a jet engine strapped to a bicycle.

The pulse jet's not a bomb.

It's just an engine like anything else.

It's just a kind of the model T of jet engines.

As far as dangerous it's about as dangerous,

as the car that you’re driving.

Other than they get extremely hot.

[motor blaring]

[narrator] Bob's motivation is pure and simple, he likes speed.

[Bob] Loud is fun. Fire is fun. Explosions are fun.

I guess that's the draw to it.

[narrator] Being on a limited budget,

he made his own V1 pulse jet engine from scratch.

So I went to my shop and I started chiseling away,

trying to figure out how to make one work.

It took a few months but,

I finally got an operational engine.

So I decided you know if you’re making something,

that makes a lot of power and thrust,

you want to put it on something to go fast.

[laughs] So...

First thing I could really find was an old cruiser bicycle,

that was leaning up against the wall at my shop.

[narrator] After the first run on that rickety bike,

he was hooked.

It felt pretty darn good because it pulled pretty hard.

It made about 60 pounds of thrust,

and it took off pretty good, it was a lot of fun.

The little jet bikes are a lot of fun to ride.

[narrator] Bob used to spend his time,

making tiny delicate pencil strokes as a fine artist.

It really wasn't my speed,

and talking to all the artsy-fartsy people.

I felt you know, a little out of place.

It didn’t hold my interest.

Like designing and building the jet powered vehicles,

and stuff that I do.

[narrator] Now he's molded his talents into hand crafting,

these engines from flat pieces of metal.

[motor blaring]

What I’m trying to do is build up,

a limited edition really high-end type of bikes.

Probably in the 25-60 thousand dollar range.

[narrator] He also sells designs engines and kits online.

So you too can build your own jet powered stuff!

At first glance, the engine just looks like an empty tube.

But that's just the beauty of the design.

[Bob]The whole tube is the engine.

You set off an explosion up in the front of it.

And all the gases rush out the tailpipe.

[narrator] Here’s how it works.

[Bob] The way the pulse jet engine runs,

is it has to create turbulence,

that mixes the fuel and the air together.

And when that fuel and air mixture,

get down to the spark plug,

the spark plug sets it off, and goes off like a cannon.

Boom! When it does, it shuts this one-way reed valve,

causes all the gases,

to rush out of the tail pipe, just like a canon.

At supersonic speed. So that creates a suction.

It creates a negative pressure inside the whole engine.

It opens the one-way reed valve.

Sucks air which mixes with fuel that's spraying all the time.

And then there’s so much negative pressure here

that is sucks air all the way back up the tail pipe.

And it brings some of the fire from that previous explosion

back up with it and the fire that it brought back up,

sets off that new charge and bang it goes off again.

And like a canon again,

the whole sequence repeats.

So it's like a canon going off 70 times every second.

[narrator] The complexity of it all is forgotten,

when Bob forgets his pedals and starts to melt metal.

[Bob] When you’re riding it,

you just have to get it into your head

that you’re riding a motorcycle not a bicycle.

cause if you’re thinking I’m going 60 miles an hour

or 83 miles an hour, you just don’t want to think

that I’m on a bicycle with bicycle tires.

You want to think I’m on a motorcycle.

And it's going to hold together!

And those tires aren’t going to blow apart any second!

[narrator] Bob's next project is putting one of his engines

into a vintage Lakester.

The amount of thrust in this one

could take Bob to speeds of epic proportion.

[shouting]

[Bob] So it only weighs about 700 or 750 pounds,

and the buzz bombs weighed 4500 pounds,

and flew 400 miles an hour.

So it should be able to go fairly fast.

[motor blaring]

[narrator] His only challenge with that,

will be getting the Lakester back home with his bike,

at least he has options.

Good thing I have pedals.

[chuckles]

Well that's it for today, I’m Basil Singer.

Thank you very much for watching,

How Tech Works. See you next time.

[ending music]