51x20 - Building Stuff: Change It!

[bunniefuu]

NARRATOR:
We live in a built world.

Engineering and technology,

built upon
innovations and inventions,

stretching back
thousands of years.

Some of our creations,
like machines,

boost our bodies' abilities.

Others help us reach
outside our comfort zones.

We have left an indelible mark
on the planet.

And now the time has come
to use our skills

to make a better world.

WORKER: two, three, lower.

NARRATOR: Like
inventing a new way to fly,

electrically.

Or a device that can smell...

ANN PERSON: I get very
excited when technology works.

NARRATOR: to save
food from going to waste.

THARINDU MADDUMA: Food
waste is enormous global problem.

NARRATOR: Creating a machine...
RESEARCHER: Rob, I'm going in.

NARRATOR: to
heal coral reefs.

ARAN MOONEY: How do
we fix the environment that's

sort of dying in front of us?

NARRATOR: Or even
combining a traditional work of art...

LEWIS STETSON ROWLES: We see
this amazing opportunity to use pottery.

NARRATOR: with
modern chemistry...

NAVID SALEH: Could you
actually make something like that?

Do you have something similar?

NARRATOR: to provide
clean drinking water.

I made a shape similar to that.

NARRATOR: "Building
Stuff: Change It!"

Right now, on "NOVA."

♪ ♪

NARRATOR: Human beings have been

changing our surroundings
for thousands of years.

The signs are written
on the land itself.

We're builders and makers.

And the evidence
is plain to see.

ADAM STELTZNER: Our
whole lives are constructed.

We live in the modern world
in a very altered environment.

And all of that alteration

starts and finishes
with engineering.

ANDREA ARMANI: Engineering
can transform a community by

bringing power, bringing
water, growing food.

DEB CHACHRA: Taking sewage
away, the power grid, telecommunications,

these are all
engineering systems

that are not about
making any one of us

smarter or stronger or faster,
but making us, collectively,

have more agency
and more capacity.

NARRATOR: But
building the modern world

has come with steep costs

and changes to more
than just the land,

like altering the chemical
composition of our atmosphere.

But now there's a new generation

that wants to engineer
a cleaner planet.

So, as an engineer,

when you see the world
as it is, you begin to think,

"How could we make it better?"

So that's our job, to
take the world as it is

and make it better.

Everyone's
engineering background,

it comes from that
purpose of saying,

"I want to solve a problem
that just changes the world."

NARRATOR: One daunting
challenge we face today

is to reduce the
carbon emissions

caused by burning fossil fuels.

Electrifying transportation
offers some hope.

On the ground,
cars, buses, trucks

and trains are gradually
making the switch.

But what about in the air?

Is there a way to
go green in flight?

At Joby Aviation in
Marina, California,

engineers think so.

They're testing a
new kind of aircraft.

WILSON: So, today,

uh, Joby's flight test team

is putting the aircraft
through its paces,

flying range and
endurance missions.

NARRATOR: The
aircraft is a hybrid...

like a helicopter, able
to take off vertically,

but also, like an airplane,

able to fly horizontally
at high speeds.

And it's completely electric.

ARMANI: The
challenge is, you know,

how do we make a
personal helicopter?

How do we make them sustainable?

Right, we don't want to bring
more jet fuel into the world.

WILSON: It is
routine for us to fly

three times a day, cruising
around at about 100 knots.

NARRATOR: Joby's ultimate dream

is to deploy the aircraft
in cities around the world

as flying taxis,

reducing congestion
on the ground.

Today they're in the
final testing stages

of their latest prototype.

But despite promising results,

they're not taking chances
with humans on this round.

WILSON: There's
actually nobody on board

the aircraft
while it's in flight.

The pilots are simply
sat on the ground

in the ground control station,
flying the aircraft remotely.

NARRATOR: Technically,
it's known as an EVTOL,

Electric Vertical
Take Off and Landing.

But it's also capable
of level, forward flight.

As we're going through
our airspeed expansion,

we are testing a,
a certain airspeed,

performing a bunch of tests

to make sure our
aircraft is stable,

and then expanding into
different airspeed regimes

all the way to fully
wing-borne flights.

NARRATOR: This day's
testing is winding down.

A sudden tilt on touchdown
is quickly corrected

by the remote pilot.

Something to tweak
for future flights.

WILSON: Our analysts
look at the data after the flight

to make sure that the
aircraft is performing

exactly as we expect it to.

NARRATOR: As Joby engineers
work to realize their dream,

significant engineering
challenges remain

before regular passenger
flights become a reality.

DARAIO: As you're trying to
develop transportation devices,

you really need to
understand the environment

in which these
systems need to operate

and iterate the
engineering design,

the components, the testing
specifically to those needs.

NARRATOR: Today, it's not
uncommon to see helicopters in city skies.

But they have drawbacks.

They're noisy, the learning
curve to fly them is steep,

they have limited forward
speed, and they burn fossil fuels.

Joby's design is an attempt to
address all of those problems.

VALERO-CUEVAS: You
have identified a problem.

Can you make an airplane

that uses propellers
like a helicopter

but doesn't have that noise?

Well, you've dreamt it up.

The question is,

how do you actually
bring it into existence?

WORKER: All right,

one, two, three, lower.

NARRATOR: One of
the biggest challenges

has been to invent a
new propulsion system.

The idea was to design a vehicle
for four passengers and a pilot

that can rise
straight off the ground

and then somehow
transition to fly like an airplane.

Joby's solution...
six electric motors

that can individually pivot,

propelling the vehicle
up to 200 miles per hour,

eliminating fossil fuels
and reducing noise,

a critical improvement

if they have any hope
of widespread adoption.

That's what gives the
aircraft its unusual profile.

Six smaller propellers

that are quieter than a
single helicopter blade.

But because they're small,

everything depended on
finding the right propeller shape,

a surprisingly
complicated problem,

part art and part science,

with much of the know-how

handed down since the early
pioneers of powered flight.

These propellers may
seem wholly modern.

But if we trace their evolution,

we can see clear
connections to the past.

Leonardo da Vinci's notebooks

contain one of the most
famous early conceptualizations

of a device resembling
the modern propeller.

Da Vinci, in turn, may
have been inspired by

the Greek philosopher Archimedes
and his screw-shaped water pump,

or even by nature.

Certain plants and seeds,
like the maple and sycamore,

have evolved similar shapes.

When they fall from
trees, they look and work

remarkably like
helicopter blades.

At Joby, the design team
is looking for the best shape

to balance power and noise.

We went through a
lot of experimentation

with actual propeller,
uh, prototypes.

We needed to put real work
in, in terms of experiments,

to really understand
this phenomenon.

NARRATOR: To reduce noise, it
helps to understand what causes it.

As each propeller blade
slices through the air,

it creates pressure vibrations.

The strength of those vibrations

depends in turn on
a propeller's shape,

how fast it spins

and the number of blades.

MIKIC: So we iterated
with a number of designs.

We took blades with
a lot of blade area

and then much thinner
blades and, uh, trying to see

how that results in
acoustic generation.

These propellers are
turning much slower

than traditional
helicopter blades.

We varied the shape,
a lot of experimentation.

I think this trial
and error system

is something that allows us
to ever more refine design,

produce and, uh, test,
which, in multiple iterations,

allows us to arrive to,
uh, to optimal solutions.

NARRATOR: The company
has tested several blade shapes,

hoping to find the
best combination

of efficiency,
lightness and durability.

To test each new
propeller design,

the company has built
a large circular track

in an old quarry
near Santa Cruz.

MIKIC: In quarry, we have
what we call "The Whirlybird,"

which is a track kind of
like a roller coaster track

that goes around in circles.

And we have to
test this propeller

not only in hover conditions,
but through all the conditions

that it experienced
through transition

as well as forward flight.

NARRATOR: On the track,

they test each
iteration of the propeller

for durability and blade design,

as well as for noise.

MIKIC: And then we adjust
the angle of the propeller,

the speed of the propeller,

the variable pitch on it

to see how it operates in
different regimes of flight

that the real airplane
would experience.

And we can do this
for hours on end,

days on end, uh, to see
how the system performs.

ARMANI: The
design of a propeller

is a very
theoretically heavy lift.

However, at the end of the
day, experimental results rule.

And their ability to
build that huge test ring

to really, you know, compare
their experimental results

with the, the
theoretical predictions

are really what
allowed them to advance

and push their
entire plane forward.

NARRATOR: Ultimately, they
discovered that their original design,

which was wider,

actually performed better than
subsequent slimmer designs.

The greater surface area
allowed them to slow down

the propeller's rotation speed,

reducing noise while
meeting power requirements.

MIKIC: When you
do the experiments,

you realize you're going down

the wrong path, then you
start to go back and see,

like, well, why is the
thing that I tried to do

that makes things
better actually worse?

So you challenge
your own assumptions.

DARAIO: Challenging
assumption is something that

is an essential
component in engineering.

Being able to harvest the
advances of divergent thinking

and creative thinking

is something that, in the end,

promotes innovation
and allows us

to advance
technology much faster.

NARRATOR: A change to
the shape of the propeller

helps with the
nature of turbulence

generated by the blade.

Exactly how they did it,

a Joby representative
said, is a trade secret.

But the result is a vehicle
that the company says

produces 100 times less
acoustic power than a helicopter.

Eventually, they're hoping
to expand their test program

to include passengers

and move toward
full certification

from the Federal
Aviation Administration.

DIDIER PAPADOPOULOS:
Safety is non-negotiable.

Look, I'm gonna put my
kids on these airplanes,

and so this is,
this is close to me,

just as it is close
to everybody else.

WILSON: Now being able to travel

routinely with an
aircraft like this,

and be able to do
it relatively low cost

and super available to
the masses, is so exciting.

NARRATOR: Today, air travel
accounts for an estimated 10%

of the carbon produced
by all transportation.

It's this kind of
experimentation

that could lead to bigger
changes in air travel.

Electrifying aviation
is one of the hardest

engineering challenges we face.

But not every problem
requires such a difficult solution.

When it comes to finding ways
to reduce carbon emissions,

there is some
lower-hanging fruit.

Over thousands of years,

we've gotten more
and more efficient

at growing food for an
ever-growing population.

But the road from farm to
table can be long and wasteful.

Globally, a third
of all crops go bad

before they reach the table.

And with food production
accounting for about 30%

of global greenhouse
gas emissions,

reducing food waste
could be one solution

to our climate problem.

At least, that's the idea behind
a Norwegian rot-sniffing robot.

The BAMA food
warehouse in Oslo, Norway.

NARRATOR: Anne Person is
the director of quality assurance.

We get about 2,000 pallets

in here every night.

NARRATOR: The produce
comes in from 80 countries.

They're being scanned here.

And then they go straight
to the quality control tower.

This is the first control
that is being done

when it comes to Norway.

NARRATOR: Inspectors
screen the produce

for spoilage, as best
they can, before sending it

to the supermarket.

The problem is we don't
have very much time

to inspect the pallets.

It's maximum 60 seconds.

And also, due to the
setup of the quality stations,

we are only able to control
the two upper layers, maximum.

NARRATOR: That means,
even with experience,

visual inspection
only goes so far.

Inevitably, some spoiled
produce goes undetected

and gets shipped along
with the rest of the produce

all over Norway to
local supermarkets.

PERSON: So our question was,

how can we check
the whole pallets?

So that's when we started
to look at the new technology.

The goal is increased freshness
and reduced food waste.

If you can detect spoilage
earlier in the value chain,

we are also able to do more

with the products
that we might reject.

We can sort them, we can
give them to food banks.

NARRATOR: BAMA connected with
Tunable, a small tech company in Oslo,

inventors of an artificial nose,

or machine olfaction device,

that is already
in use monitoring

the amount of greenhouse gasses

emitted by container ships.

Tharindu Madduma is Tunable's
business development manager.

MADDUMA: BAMA came to us.

They explained that
they had this problem

of determining the quality
of the fruits and vegetables,

being able to do
it at a large scale

and being accurate.

VALERO-CUEVAS:
There's a long history

of inventions

that allow us to
extend our senses.

So we've done that for sight.

We've done that for hearing.

MADDUMA: So, we have
microscopes, we have hearing aid,

but smell is still a sense

that we haven't digitalized.

And that's what we're doing.

NARRATOR: Kristian
Hovet is Tunable's C.E.O.

HOVET: When you take a breath,

you're doing a
multi-gas analysis.

You're pulling in molecules,

and those molecules
are detected by your nose,

and then it's
detected by your brain

to tell you what
you're smelling.

NARRATOR: The
challenge for Tunable

was to take their existing
analyzer for emission analysis

and increase its sensitivity

without making the device
too big and cumbersome

to be useful on a
warehouse floor.

So why use smell?

Our noses are
sensitive detectors,

able to identify a wide variety

of chemicals in the air,
even at low concentrations.

Airborne molecules can
also potentially reveal

what's hidden in the pallets.

These molecules
tell a chemical story

of fruits and
vegetables as they rot.

But the device would have
to be far more sensitive

than a human nose, and
able to detect spoilage

more reliably than a human eye.

Produce, like all living things,

decays after death

as microbes consume dead cells,

releasing volatile
organic compounds.

In theory, the team should
be able to tune their machine

to recognize those molecules.

We knew that we could
look at complex gasses.

We redesigned emission
analyzer, and then we started testing.

NARRATOR: Eivind Jülke Røer

is the lead engineer on
the Tunable e-nose project.

RØER: So now I'm going
to measure fresh grapes

and then some spoiled grapes.

See our e-nose can
smell the difference.

I'll start with collecting

a sample from the ambient air

as a baseline for
the measurement.

[machine whirring]

And the noise you can hear now
is actually the compressor pump

pulling air, uh,
into the analyzer.

So now I'm going to take a
sample from the fresh grapes

to see if there is
anything present there.

NARRATOR: The probe pulls in air

and then compresses it

by a factor of five,

which increases the
density of the sample

and makes molecules
easier to detect.

Next, infrared light
shines through the sample.

The light then
passes through a chip

that sorts different
types of molecules

based on the
specific wavelengths

of light they absorb,

which ultimately
allows the analyzer

and accompanying
software to reliably detect

the presence and concentration

of molecules that
signal spoilage

with extreme sensitivity.

RØER: The reading I got now

doesn't really show any
molecules present at all

compared to ambient air,

which is more or less what I
would expect from fresh fruit.

[machine whirring]

So now I'm going
to take a sample

for the, um, spoiled grapes.

We see a clear difference.

We see up to 12% absorption

at ethanol wavelength,
which is a good indication

that we actually smell
the rotten grapes.

So, uh, this looks
really promising.

HOVET: The fumes
we were able to collect,

we were able to see the,
the kind of the signatures.

NARRATOR: The
engineers then tested

different kinds of
fruits and vegetables

as they decayed, building up
a database of chemical profiles.

HOVET: We saw a tomato was
different, somewhat, from a banana.

Grapes were different
from avocado, for example.

And we thought, well,
this must be interesting.

[laughs]

[compressed air can sprays]

NARRATOR: Thor Bakke

is the founder and Chief
Technology Officer of Tunable.

He's been working with
microelectromechanical systems

for over 30 years.

BAKKE: Tunable is a component,
uh, inside our analyzers.

That's the Tunable filter.

It's used to change
the wavelength of light

so we can scan the
wavelength and do spectroscopy.

[radio playing static
between stations]

Spectroscopy is
very much like, uh,

tuning a radio to find
a particular station.

The gasses are separated
in the infrared spectrum,

just like radio stations.

And then you can basically
detect each one of them.

So that's where the
word Tunable comes from.

NARRATOR: After
extensive fine tuning in the lab,

it's time for the very first
field test in the warehouse.

STELTZNER:
Sometimes you can't learn

about all of the variables

that will be involved in
an engineered system

sitting on a desk

with a pen and paper
or at a computer screen.

You need to go
out into the field.

You need to put it in
the actual environment

and see how it interacts,
learn from that, make changes,

and move forward.

RØER: Now I'm
capturing; I'm in there.

Now I'm ready to do the
measurement on the grapes.

NARRATOR: Eivind
watches the screen,

waiting to see the
telltale grape waveform.

But the pump just whirrs away.

And eventually he gives up.

Uh, I don't really know
what happened here.

Uh...

For some reason, um, the
results wasn't as expected.

NARRATOR: The first time
definitely wasn't the charm.

Murphy's law.

Yeah.

HOVET: We know that it works
in a laboratory environment.

So the big thing now

is showing that
it actually works...

[chuckling]: in real life, and as you
see, there's been some challenges.

CHACHRA: We tend to think
of failure as a bad thing, right?

That something that is not
supposed to happen, happens.

But if you're doing
anything new,

failure is an integral
part of the process.

And the reason for
that is because we can't

perfectly predict or understand
how things are gonna work

in the real world
until we try them.

NARRATOR: Turns out
the warehouse temperature,

a chilly 41 degrees Fahrenheit,

affected the test result.

HOVET: The cold part.

We did know that it
was cold in that area,

but did we take it
on account enough?

No, we didn't.

We should, of course,
have thought about that.

But, uh, but that's the
kind of the learning,

that's the process.

NARRATOR: Back in the lab,

the Tunable team
recalibrated their chip

to account for the BAMA
warehouse temperature.

They also adjusted the design

to include the pumps
that compress the sample,

increasing the
density of the gas

to compensate for the
lower metabolic rate

of the food in the
refrigerated environment.

RØER: It will be
really interesting to see

if the alterations
we have, uh, made,

will actually do the
difference in the field.

NARRATOR: Eivind is back with
the latest iteration of the e-nose.

Further testing in the lab

showed that, even
with the changes,

the machine needs time
to adjust to the conditions

in the warehouse.

RØER: Now, I'll let the
instrument stay here for the night

to reach a steady temperature,

and then we'll do
measurements tomorrow.

♪ ♪

Well, after a long cold night,

the system should
be ready to go.

[machine whirring]

Now we see absorption of light

at more or less


which, um, indicate
ethanol being present.

This really shows that
our new chip is working

in this real environment.

NARRATOR: Eivind uses the e-nose

to sample the air
from various locations

on the entire pallet stack.

RØER: Actually, we see a spike at
the ethanol absorption wavelength,

so that might be something.

NARRATOR: They've
taken an important step.

A successful real-world test

of the newest version
of the Tunable e-nose.

I'm not the most
excited guy, but, um...

[giggles]

this is, uh, this is exciting.

[e-nose humming]

I expected it, although
you never know.

It's a big win.

I get very excited
when technology works.

NARRATOR: Still, there is work
ahead to make the technology viable

and, most importantly, scalable.

MADUMMA: We hope that we
can make them more efficient.

Food waste is
enormous global problem.


comes from food waste.

So if we can be a part
of the solution, it's huge.

NARRATOR: Reducing food
waste is one of many ways

engineers are trying
to slow climate change.

But the negative changes
we've made to our climate

are already damaging
some environments

like coral reefs.

MOONEY: Coral
reefs are in decline.

So one of the things
that I really think about

is how do we fix the environment

that's sort of
dying in front of us?

NARRATOR: Healthy coral
reefs can be stunningly beautiful

and play a critical role
in coastal ecosystems.

They harbor a tremendous
diversity of marine life

and contribute to
the overall health

of the world's oceans
and their coastlines.

A quarter of all marine species
depend on them for survival.

They're also
important to humans.

Often located in shallow water,

they can protect
coastal communities

from damaging storm surges.

And the reefs host a primary,
sustainable food source

for hundreds of millions
of people around the world.

But as the oceans warm,

corals are
struggling to survive.

Excessive heat drives
away the microscopic algae

the coral depend on.

That leads to a
dramatic loss of color,

known as coral bleaching...

a powerful visual indicator
of an unhealthy reef.

But bleaching isn't the only
indicator of a reef in peril...

MOONEY: Not only it looks brown

and is lacking these
beautiful, vibrant colors,

but it just sounds dead.

[underwater ambient noise]

NARRATOR: That's where sensory
biologist Aran Mooney comes in.

MOONEY: My background is
in hearing and in bioacoustics.

And I study how animals
perceive the world around them.

[wildlife chittering]

Coral reefs are kind
of rainforest of the sea,

and just like a
really rich forest

might have a lot
of birds calling,

and you might hear the
monkeys calling in the background,

coral reefs are really the same.

So basically a
healthy coral reef

has a really healthy
rich soundscape.

[crackling, snapping]

NARRATOR: Snapping
shrimp, lobster, and fish

create a symphony indicative
of a biodiverse community.

MOONEY: And a degraded coral
reef is just an impoverished soundscape.

It sounds quiet,
kind of desolate.

So, by listening
to the soundscape,

we can kind of
track that biodiversity

and understand when
that change is happening.

♪ ♪

NARRATOR: Off the coast
of St. John in the Caribbean,

a team from the Woods
Hole Oceanographic Institution

in Massachusetts

conducts bleaching surveys,

finding evidence
of degraded reefs.

[water splashing]

To your right, there's
some bleached coral.

You knew there's going
to be bleaching here, right?

But then it's freaking
everywhere, right?

YOGI GIRDHAR:
I've been coming here

five or six years now,

this was the first time

I have seen such bleaching.

NARRATOR: Yogi
Girdhar is a roboticist

and computer
scientist at Woods Hole.

GIRDHAR: I am working on

robots and A.I.

and machine
learning-based techniques

to understand complex
ecosystems in the ocean,

such as coral reefs.

NARRATOR: A question they pose:

is it possible to build a robot

that can seek out
and find healthy reefs

on its own? [electronic beeping]

If they succeed,

the robot could provide an
efficient and cost-effective way

to find healthy coral
reefs, map them,

and monitor their health.

[electronic crackling]

The soundscapes
recorded by the robot

could be a vital tool in
diagnosing reef health

and tracking decline
or improvement.

♪ ♪

MOONEY: Good job, team!

♪ ♪

NARRATOR: The team has
been collecting data on reefs

for over a decade.

You're going through this. Yeah.

I might be able to
thread it through here.

NARRATOR: They have
mountains of information;

including audio and video.

They've even created


for further study.

Helping them gather this data

is this third-generation robot.

GIRDHAR: We call it CUREE...

C-U-R-E-E.

It stands for Curious Underwater
Robot for Ecosystem Exploration.

NARRATOR: It's equipped with
sensors, microphones, and cameras

and is still very much
under development.

GIRDHAR: The design of a robot

is always evolving.

Our robot is never finished.

NARRATOR: It's an
engineering challenge

with a lot of moving parts.

So they've broken it down
into many small steps.

MARIA YANG: There
are many, many problems

that you can solve with
an engineering solution.

But I think you have to

really understand
what the problem is

and sort of pick
the two or three

that really you want to address.

Otherwise, you kind
of fall into this trap of

trying to solve all the
problems all at once

and you run out of resources.

♪ ♪

NARRATOR: This morning, the
team is prepping for its latest test

right off the dock.

MOONEY: All right, Dr. Girdhar.

Are you ready?

Always.

GIRDHAR: I'll manage
the tether. Got it?

NARRATOR: To start, they'll
place a speaker on the ocean floor,

playing a recording
of a healthy coral reef.

A sound file they captured

from a previous trip.

SETH McCAMMON: It should be on.

GIRDHAR: Yeah. All right.

We hear it.

[electronic crackling]

NARRATOR: They're
hoping the robot

will recognize the
sound through the water

and be able to record it.

In this outing,

the robot is not
moving autonomously.

Researcher Seth McCammon

is operating the robot remotely

to steer and
position it for the test.

I'm getting it in
line with the thing

so we can start
to look at the data.

GIRDHAR: If the robot
doesn't work with this sound,

it's probably not going to
work on the real coral reef,

so it's a good, good test.

NARRATOR: Experimenting
with sound underwater

is not a new idea.

In the 1800s,

a Swiss physicist and a
French mathematician,

armed with a bell and stopwatch,

measured the speed at which
sound traveled underwater.

On one side of Lake Geneva,

Charles François Sturm
rang a submerged bell,

[bell ringing] while
Jean-Daniel Colladon

used a long tube to listen
underwater across the lake...

[watch clicks]
pressing his stopwatch

to keep track of
how long it took

the sound to travel across.

Surprisingly, they
found that water

is a better conduit
for sound than air.

Sound travels through water

roughly five times faster.

Today, the Woods Hole team

will be using the speed
of sound underwater

as part of their calculations.

The robot is equipped

with four microphones
designed for underwater use

called hydrophones.

As the sound from the speaker
speeds through the water

in all directions,

it reaches the hydrophones
at slightly different times...

just milliseconds apart.

The researchers look
at a computer display

that shows the
signals recorded...

[electronic chirping]
on each hydrophone.

McCAMMON: And so it will hit
one hydrophone before the others

and by looking at the
relative time of arrival

at those different hydrophones,

we can figure out which
direction it came from first

and then steer the
robot in that direction.

♪ ♪

NARRATOR: The
robot correctly identifies

the direction of the sound...

an important first step
toward autonomous navigation.

♪ ♪

A small but important victory.

♪ ♪

McCAMMON: It's like
you're building out of LEGOS

and you're building up a house,

brick by brick by brick.

And it only works

when the house is fully done.

But you need to know

that each single brick in that

works on its own in isolation

before you're willing to
add it to the larger picture.

MABRY: And so, you
have this massive goal

that you're trying to achieve,

but there needs to be
attainable goals along the way

because ultimately,

you're dealing with a
system of components,

a system of elements

that need to work together

in order for this

to be successful.

NARRATOR: CUREE
is ready to step up

to a bigger challenge.

Locating an actual
healthy reef by sound...

something less predictable
than what the speaker provided.

One of the healthier
reefs in St. John

is in nearby Joel's Shoal.

GIRDHAR: I propose
we drop the robot

like 20 meters...

MOONEY: We're like ten meters

off the reef right now.

NARRATOR: They'll place CUREE

approximately 20
meters from the reef.

[electronic chirping]
To succeed,

it just needs to orient itself

toward the sound.

Robot going in.

All right, cast away!
[electronic melody]

McCAMMON: So the test today

is mostly just
trying to figure out

if the robot can
accurately determine

which direction
the reef sound is in.

NARRATOR: It's a
more complex test.

This time CUREE is untethered

and the boat is drifting
with the ocean current.

NARRATOR: If they lose contact,

they could easily
lose the robot entirely,

and all of the engineering
that went into it.

♪ ♪

MABRY: When they began to
design this autonomous robot

that would go underwater,

there is a need
to make sure that

this thing is able to behave

in an environment
where, if it doesn't,

we can retrieve it...

NARRATOR: CUREE locates
the direction of the healthy reef.

Which is encouraging.

NARRATOR: It's
another successful test.

[electronic crackling]

The next big hurdle,

can CUREE not only locate,

but then move towards a
healthy reef autonomously.

This will be a crucial
milestone in the mission,

which is to ultimately
build a fleet of robots

to map, monitor, and record

the health of corals
around the globe.

While reefs are under
serious threat all over,

there are some signs of hope,

and some surprising ideas
for ways to protect them;

including one that came
from this team's research.

♪ ♪

In their work, they discovered
that the sound of a healthy reef

might actually have
an indirect healing effect

on a stressed reef.

It has to do with the
coral animal's life cycle.

Newly born baby corals...

tiny larvae...
drift in the ocean,

searching for
somewhere to settle.

It turns out the sound
of a thriving coral reef

signals them to
settle into place.

Once they find a spot,

they can be very resilient

and grow for centuries.

So the more larvae
a reef can attract,

the healthier it will be.

And that gave the team an idea.

We know these reefs are degraded

and we want to rebuild them

by attracting the
larvae, the baby coral.

NARRATOR: In a past experiment,

the team found that larvae

could be drawn to
recordings of healthy reefs.

So by placing speakers
in strategic locations,

they could give a boost
where it's needed most.

MOONEY: And that system actually

leverages the healthy landscape

and plays it back
into the environment

and the idea is that
it induces coral larvae

to kind of choose that
environment and settle.

NARRATOR: The result?

Up to seven times
more larvae settlement

compared to a degraded reef

without the audio boost.

A very encouraging sign.

♪ ♪

But back to St. John and CUREE.

The team is ready for
the final test of the day.

McCAMMON: The robot
is going to use the direction

that it's finding
from its hydrophones

and then drive itself

to whatever the nearest
acoustic source is,

which we're hoping is
going to be Joel's Shoal Reef.

NARRATOR: This time,
since CUREE will pilot itself,

it's tethered for safety.

They put CUREE in the
water and give it the green light.

NATE FORMEL: Are we expecting it

to be moving or not?
McCAMMON: We are.

NARRATOR: It looks at
first as though it's orienting

toward the sound of the reef.

It thinks it's moving.

NARRATOR: But after
a few minutes it's clear

that CUREE isn't
making much headway.

It's just dumb stuff in
the way that I wrote.

NARRATOR: It seems there's
an issue with the software.

♪ ♪

All right, bring it back.

[ratcheting]

It's coming up.

FORMEL: I can now see it.

NARRATOR: They're
starting to lose the light.

It's getting dark.
[indistinct chatter]

NARRATOR: They weren't
able to check off everything

on the day's to-do list,

yet they remain upbeat.

GIRDHAR: Overall, I am
happy right now because...

McCAMMON: We ended
the day with as many robots

as we started the day with.

NARRATOR: It's
frustrating in the moment,

but they're making progress.

STELTZNER: The
creative act of engineering

has got disappointment,

has got failure,

and that's how we learn.

[chuckling]: So, it
is a big ball of, of...

two steps forward
and one step back.

When you have a
very massive "Why"

and a very massive purpose
for what you're trying to do,

such as save the coral reefs,

it allows you to experience
the disappointment

but not be defeated by it,

and continue to try the
process of moving it forward.

♪ ♪

If you're not failing you're
not trying hard enough.

[voiceover]: Yeah,
it's very frustrating

but when it works,

it's very satisfying.

NARRATOR: Engineering
solutions to the climate crisis

will require
creativity, innovation,

and a global commitment
to making smart choices.

But we face many
other challenges as well;

like restoring
balance to the land

after decades of
industrial pollution.

♪ ♪

On Navajo land in Arizona,

an Indigenous artist and
engineers are collaborating

on a unique, local approach

to purifying contaminated
drinking water.

[birds chirping] This
pristine-seeming landscape

conceals a serious problem.


in the Navajo Nation

lacks access to
clean drinking water.

Decades of uranium mining

has polluted the land.

The United States government

used the heavy metal

to develop the atomic b*mb

and power its nuclear
weapons program

after World w*r II.

CHACHRA: When
we think of engineering,

people are suspicious
of it because,

for a good part of
the 20th century,

one of the stories
of engineering

was engineers making
decisions about systems

that affected a
lot of other people.

And often those
effects were not positive.

NARRATOR: Byproducts
of uranium mining,

such as strontium,

can mimic calcium in the body,

causing it to be
absorbed by bones.

The E.P.A. has
awarded $3.8 million

to support three
drinking water projects

to benefit the Navajo Nation.

Some are proposing other, more
homegrown solutions, as well.

[stone grinding]

Deanna Tso is a third-generation

Navajo artist who works in clay.

TSO: People always ask me,

"When'd you learn
how to do pottery?"

I always say,

"I was born making it."

Both my parents, my
mother and my father,

both did Navajo pottery.

[car doors closing]

NARRATOR: She has been
collaborating with scientists

Navid Saleh and
Stetson Rowles...

[knocks on door]

Hey! Good morning.

Hey, Deanna.

NARRATOR: on a
project meant to address

the water contamination problem

on a very human scale.

SALEH [voiceover]: I believe
that engineering without people

is destined to fail.

Good. Good. Long drive.

SALEH [voiceover]: There
is this experiential knowledge,

knowledge that is housed
within people's lives,

yet to be unlocked.

NARRATOR: Not
all people here use

or have access
to municipal water,

so the goal is to call
upon local knowledge

to find a sustainable
way to purify water

closer to the home.

YANG: We often think

of engineering as only being

the latest and
greatest technology.

But, people have practices
that are very effective now

and, and have been for,

you know, decades,
centuries longer.

And so what can we learn
from those, existing approaches

that are already effective?

So Deanna, this
was something that...

NARRATOR: On this trip,
the scientists want to build

a new prototype clay filter

for use in household
water containers.

The hope is to integrate
locally sourced minerals

so that the finished filter will
remove uranium byproducts,

like strontium, from the water.

SALEH: Could you actually
make something like that?

Do you have something similar?

I have one that I make

with the cone shape.

NARRATOR: Navajo
potters like Deanna

use a local tree sap as a glaze.

Navid and his team wondered
if the sap could be used

as part of a
decontamination filter.

SALEH [voiceover]: What we
found was how much knowledge

the Navajos already
had about the sap.

They already knew
it has health benefits.

So this is a printout of the...

NARRATOR: Navid and his
team recently conducted tests

that translated
Indigenous knowledge

into the language
of biochemistry;

quantifying the extent of the
sap's antimicrobial properties.

Now, they hope to expand
the filter's capabilities

to radioactive contaminants.

YANG: They worked
together, collaboratively,

to make something new and better

that serves her community
in a really, powerful

and very collaborative way.

We can engineer
a shape or a design

that's going to work well,
not only to filter water,

but people will want to use.

[voiceover]: We see
this amazing opportunity

to be able to use pottery,

or ceramics, as filters,

because it's so a part

of people's everyday life.

Particularly in places
like the Navajo Nation

where traditional
practices are so important.

TSO: Okay.

ROWLES: Which way?

NARRATOR: Navid and Stetson want
to learn the process of making pottery

the way Deanna's
mother taught her...

because collaboration
is strongest

when it is truly
interdisciplinary.

TSO: Yes.

You see that gray spot?

NARRATOR: Deanna
starts from scratch,

harvesting clay from
a rocky outcropping

on Navajo land.

Okay, so this portion is what?

That portion is clay. Okay.

SALEH [voiceover]: We
often as scientists believe

that we know a lot.

But we forget,

science as a discipline

has only been
around for 500 years.

NARRATOR: There are many
ways of generating knowledge

besides the modern
scientific process.

CHACHA: These
are all different ways

in which we interact
with the physical world.

That diversity
gives you new ideas.

And thinking about
how to put together

old technologies
and new technologies

might lead to
entirely new paths.

It creates a symbiotic effect,

because the more
people feel included

in what is being
produced by something,

the more people see
themselves being a part of

the producing of that thing.

NARRATOR: Next... they
source sap from pinyon trees.

There's one right here,
let's check this one.

♪ ♪

[crunches] ROWLES: Whoo!

We hit the jackpot
with this tree.

TSO: We were
blessed for the day.

Come on in. [keys jangling]

I usually just take
this much out.

NARRATOR: Deanna
demonstrates how to grind minerals

into the fine grains
that make up her clay.

One of you want to go
ahead and give it a try?

ROWLES: I think
there's a lot of engineering

that goes into creating pottery.

The freedom that it
allows to make any shape.

[squeaking]

STELTZNER: The fusion
of art and engineering.

Or maybe even the boundaries
between art and engineering...

perhaps they don't exist.

Perhaps they're
really the same thing,

painted with a
different palette.

NARRATOR: Stetson and
Navid are working with Deanna

to prototype a shape
for the clay filter.

I don't know if you know Deanna,

but I've been making some
pottery since high school,

and I made this
shape to try and see

if maybe we can explore
making some shapes together.

I made a shape
similar to that...

and it looks like this.

And we do make these
traditional Navajo pipes.

Do you think you can
make some grooves

similar to something like this?

Kind of like an
accordion basically,

so it has the same surface
area but in a smaller size.

♪ ♪

NARRATOR: Adding grooves increases
the total surface area of the shape.

More surface area
will mean more contact

with the water inside.

TSO: I'm going to show you

an option we have
that we can try:

Coil. Yeah. Making a coil.

Making a coil.

♪ ♪

NARRATOR: Next,
the new prototypes

need to be fired.

SALEH: We have been
working with Deanna

for almost nine years now.

TSO: Make sure we have
it covered nice and good.

SALEH: Working
with her side-by-side

as an equal
partner intellectually,

only opens opportunities
that are more meaningful

than we scientists
would ever find

sitting at our desks.

NARRATOR: The last step:

heat and strain the pinyon sap,

creating the
microbe-resistant resin,

which acts as a glaze
to coat the pottery.

And now, a new
addition to the filter.

ROWLES: Can
you grab the zeolite?

NARRATOR: The scientists
are using powdered chabazite,

a type of naturally
occurring zeolite,

found abundantly on Navajo land.

♪ ♪

Chabazite is a porous crystal

made of sodium, calcium,
and aluminum silicates

that has the ability to trap

and absorb contaminants.

♪ ♪

Finally, Deanna
applies the resin.

TSO: The pottery
itself has to be hot.

The sap has to be hot.

NARRATOR: The team
hopes the chabazite

will add function to the resin,

removing uranium
byproducts, like strontium,

from any water that
comes into contact with it.

ROWLES: Wow, the
colors are beautiful.

♪ ♪

NARRATOR: Back at the
University of Texas at Austin,

it's time to test their water
filter prototypes in the lab.

We've got some of the clay.

NARRATOR: Using the materials

they sourced with Deanna,

the scientists create
small clay discs...

ROWLES: try
and just punch out,

a little disc like that...

NARRATOR: And coat them with
the same chabazite-enriched resin.

These are tiny lab
versions of Deanna's pottery.

To test the discs,

the researchers expose them

to strontium-contaminated water

to see if the resin will
successfully absorb

the uranium byproduct.

♪ ♪

If the filter works as expected,

the chabazite will capture
strontium from the water

through ion exchange as
the water passes through.

♪ ♪

ROWLES: Hey, Andrei. ANDREI
DOLOCAN: What's up, bud?

Here's the sample.

Yeah, thank you.

NARRATOR: Senior
research scientist

Andrei Dolocan

loads a sample into an
ion mass spectrometer.

It scans the sample

on the molecular level,

layer by layer,
over several hours.

When it's done,

the result is a map
of the elements

within the scanned
sample surface.

When the clay disc
is completely scanned,

it's time to check the results.

This is the strontium signal.

NARRATOR: The data show
that the strontium is found

in the same places as
chabazite in the resin...

DOLOCAN: We have the
zeolite, obviously sodium,

aluminum-silicon.

Uh-huh. DOLOCAN: Okay.

And now the, strontium
is increasing exactly like...

NARRATOR: It's
an encouraging sign

that the chabazite is
working as expected

when used with Deanna's
pottery technique.

SALEH: So I
guess it was a really,

successful run, Andrei.

Yeah. We can see association

of strontium with the zeolite.

DOLOCAN: I agree,
this is a good start.

ZILEVU: One thing
that I've learned

from the research
and design process

is that kind of doing

co-creation activities
with the end user,

it's really a way to kind
of bridge and create

new, innovative process,

because you're
bringing the people

who are using the technology

throughout the whole journey.

So this is the one
that Deanna made...

NARRATOR: Now a few
steps closer to their goal,

the researchers will work

to incorporate Deanna's spiral

and the chabazite's
filtering power

into their final design.

So moving forward,

I think the most difficult
engineering challenge

is yet to come.

And I think it's going to be

translating our results from,

you know, a lab scale experiment

to something that's
going to be usable

in households throughout
the Navajo Nation.

♪ ♪

[birds chirping]

MABRY: At the end of the day,

we want to unlock
human potential.

And in order to
unlock human potential,

we are not doing
ourselves a justice

if we continue to only
demand certain solutions

from a subset of
our populations,

the more we can get
more people included,

the more we can unlock

not just solutions to
problems that we now see,

but things that are yet to come.

♪ ♪

NARRATOR: As we change
our world through engineering,

it's up to us to make changes;

for all of us, by all of us.

ARMANI: I think
we're all engineers.

We all build things,

we all design things.

[chuckling]: We all break things

and then have to fix them

and put them back together.

NARRATOR: And we get to decide

what comes next.

What if we were to design this?

What if the world
was to look like this

in 50, 100 years? What
could that look like?

♪ ♪

ALI HAJIMIRI: The
engineer's work is never done...

If you're not failing, you're
not trying hard enough.

You can always
create something new.

♪ ♪

NARRATOR: Building stuff

to change the world.

♪ ♪

♪ ♪

♪ ♪

♪ ♪

♪ ♪

♪ ♪