- This is an actual death ray!
- It's a finely controlled, millimeter-precise death ray.
That's exactly what it is.
- So if this is a death ray,
that means this is a killer robot, actually.
This robot will happily murder
you and your whole family-if you're a weed.
Every weed that grows in a farm field
is taking nutrients away from the food we want to eat,
so weeds are literally trying to starve us all to death.
So, meet the robot army trying to kill them.
Why do this?
- We don't like weeds.
They're our enemy, so we're taking 'em out.
- Weed control is the number one expense for farmers,
and it turns out there's a rise in herbicide resistance
in the weed population, which means they're having
to be made more toxic every year.
- Aside from herbicides, the way we've gotten
rid of weeds is not great.
We plow them, which can get dust bowly real fast,
or we resort to the tried
and true method, back-breaking labor.
- Our focus was to not have to have humans
in the field in these grueling conditions.
- Using lasers guided by AI,
these robots can kill all the weeds
without an ounce of pesticide, and much less back pain.
- That energy just completely destroys the plants.
- How will these robots change
the way we make food?
Stick around to see how they work,
and what it'll mean for you.
This is "Hard Reset," a series
about rebuilding our world from scratch.
It might not seem like a good idea to walk
into a lab where scientists are designing
an army of killer robots,
but that depends on what those robots are designed to kill.
We came to Seattle to meet the folks at Carbon Robotics.
They're building robots that kill weeds
with fricking laser beams.
- Carbon Robotics builds the world's
first and only LaserWeeder.
We use AI, computer vision, deep learning,
and very high-powered lasers
to kill weeds in farmer's fields.
- This is Paul Mikesell,
the founder of Carbon Robotics
and owner of the world's coolest hat.
- Oh yeah, this is my LaserWeeder hat.
Well, I don't think we make these anymore.
- I was not able to get one of these hats.
- Yeah, that's right.
- These robots are the latest advancement
in an arms race with weeds that stretches back 10,000 years.
- It is an arms race, yeah, and the traditional methods
have been, you know, pull those weeds out literally by hand.
- If you're not interested in pulling weeds
by hand, we did invent the plow at one point-
which has led to all sorts
of other forms of mechanical tillage.
- Which is different forms of dragging blades
through the dirt to spin stuff up.
In the '50s and '60s, we developed a lot
of these herbicides, and it turns out these herbicides
are getting less effective every year.
It's just like how we got an antibiotic-resistance bacteria
in the human population because of overuse of antibiotics.
Well, you get the same thing in the fields.
As you keep spraying these chemicals,
the weeds that you tried to kill,
the ones that survived that spray are the tough ones.
- And those tough weeds go
on to have tough babies, which are just as hard,
or maybe even harder to kill with herbicides.
- So we need a different solution.
We knew we could make machines be able
to detect and identify crops and weeds;
we knew that that was possible.
And then the question was:
What's the best way to kill these weeds?
And lasers was just one of the things that we tried.
- I think the coolest thing about our technology
is that this is the only time where you can shoot lasers
at living things and everybody's happy.
- Well, that's probably the most
specific career goal I've ever heard.
This is Alex Sergeev. - All right.
- He's the CTO of Carbon Robotics and has a cool hat,
but not as cool as Paul's.
- So the way LaserWeeder works is, as you drive it,
it will take images of the ground,
and detect all the weeds, and track them in real-time.
- By using AI, these robots identify weeds
before humans can even spot them.
- The weeds that we're trying to kill are the smallest.
One or two millimeters is the weed
that we can detect from three feet high.
But that makes us use very high resolution cameras;
144 megapixels of just weed detection.
- The LaserWeeder uses all these cameras
and AI to identify and then track these weeds in 3D space,
so that it can feed that information to these lasers.
- And that laser beam kills these weeds
through thermal energy that explodes the cell membranes
and the cell walls of the weeds.
There's no surviving that attack.
- Like most everybody,
my favorite movies involve a laser being used in anger.
But even though these movies taught me
that lasers are dangerous and inescapable,
they've never really taught me how lasers work.
So let's find out.
Basically, the innermost tube of this laser
is filled with a mix of gases, including CO2.
As we run electricity into that mix of gases,
it excites and creates a plasma.
That plasma inside the glass tube is similar
to what you have in a fluorescent light bulb
or a neon sign at your favorite adult entertainment venue.
Anyway, all that plasma inside the tube creates
these particles that bounce back and forth
and back and forth between these two mirrors.
One of these mirrors is designed to let light through
after its reached a certain threshold.
That is a laser beam.
- How long can the laser stay on continuously?
- About 10,000 hours.
- Oh, so you can just run that laser,
if you wanted to like carve your name in the moon?
- That's right, yeah. - Can I fire the laser?
- Yeah, you can totally do it.
- Am I gonna burn a hole in the wall?
- No. - Is that like
an elementary school over there?
- No.
So here we'll do a demonstration
where we can use these little tokens.
The middle of this target is the weed.
And so we just gonna throw them on a treadmill,
it's gonna keep running, and then it's gonna shoot it
and spit out at the end here.
- Cool, shall we? - Let's do it.
- So how powerful is this laser?
well enough to mess up these wooden tokens, tell you that.
Keep in mind, these wooden targets,
while cool, are not the real enemy.
The real enemy is out there in the farm fields,
trying to starve us and our families to death.
I cannot wait to kill my first weed with a laser.
So it's one thing to design and build a killer robot,
but would farmers even want this,
when there are already so many ways to destroy weeds?
- When I saw that there was this new exciting technology
that could use a non-chemical based media
to eliminate weeds in our fields, I felt extremely excited.
Kind of like a kid in a candy store-
not to be cliche, you want it now.
- This is Josh Roberts.
He's one of the farmers who's decided to let
these killer robots loose on his farm.
- Using technology is one of the most
exciting parts of our job.
We're trying to spread the news that what we do
isn't that stereotypical farmer holding the pitchfork.
- But just to be clear, he does own a pitchfork.
- I do, I do have a pitch fork or two.
Initially, it hits you with a glaring
sensory experience from your eyes.
And then as you move closer, you start to smell
that the actual weeds are exploding as the laser hits 'em.
- I'll tell you what it smells like,
Josh, it smells like victory.
But it's worth mentioning that some of the plants
it's cooking today are actually lettuce plants,
not really weeds, but they're growing in the wrong spot,
so they're both weeding and thinning this field today.
- This opened a lot of minds, I know it did mine.
It's very valuable to us to eliminate or reduce
the amount of chemical applications in our process.
- Look, herbicides have done
a tremendous amount of good in the world.
They're a big part of what made
the Green Revolution possible,
and contributed to saving well over a billion lives.
But using chemical herbicides is a trade-off.
Some of their effects are not well understood,
and if nothing else, they're expensive.
If we didn't need to use them
to control weeds why would we?
And for some crops, using chemical herbicides
isn't even an option, which means
the only way to remove the weeds is by hand.
It doesn't sound like a fun job.
- No, it's not a fun job.
It is not an exaggeration to say
that human labor-based weed removal is back-breaking.
A lot of times those people are working
on their hands and knees,
removing plants with their fingers.
- It is very hard for farmers to find enough workers
to be out in the field and get these weeds out of there.
It gets harder every year.
- There is never going to be a shortage of work
on a ranch or a farming operation.
But what we're trying to do is curtail the need
to be desperate for that labor.
- The only thing I am desperate to do
is kill some weeds with lasers.
So I enlisted to be part of this noble cause.
So today I have gotten to accomplish
two of my lifelong dreams:
One, driving an enormous tractor very slowly,
and two, collaborating with a killer robot.
And right now it's killing weeds,
including that one that is 30 feet ahead,
that I will kill in about 14 minutes,
because I'm going so very, very slow.
So very slow.
Even though this tractor is not gonna be
in "Gran Turismo" anytime soon,
this is actually about 80 times faster
than having humans do the same work.
- To see the weeds explode, to see the weeds gone forever
and to have that satisfaction, to see that crop
come to maturity without any weeds,
is very exciting and gratifying.
It makes you think what other methodology could we use
to solve problems on the ranch?
- Problems like how we're destroying
our topsoil with intensive plowing.
- There's a reason why they think we have
only 50 to 60 good years of topsoil left in this country-
and a lot of it is because the types
of constant tillage and cultivation that go on.
- Over the past century,
as we've plowed and plowed and plowed our land,
we've destroyed a huge portion of our topsoil.
- Every time you do this, some of that topsoil blows away.
That topsoil just erodes and all the nutrients are gone.
You can't grow stuff anymore.
- That topsoil isn't just nice to have.
It's what we need to make all our food.
- So not having to dig into the dirt so much-
part of that is just the benefit of being so specific
about what we're targeting and where we're putting
that energy means we don't damage the topsoil at all.
- Technologies like this could
enable no-till farming, and allow us to replenish
that vital topsoil that literally
feeds our entire civilization.
You know, no big deal.
So, picture a scenario where we rebuilt
agriculture from the ground up
with this new weapon against weeds in our arsenal.
Ask yourself if we would use practices
like intensive plowing or spraying
chemical herbicides if we didn't have to.
Probably not.
- So if we can kill weeds today with a laser,
it makes me very excited about what's
to come in the next five years.
- With AI and lasers,
we maybe never need another drop of chemical herbicides.
And as this technology gets smaller and more nimble,
it could work in ways we can't currently predict.
- I think in 10 years we're gonna be able
to have small enough lasers that these machines
will be kind of applicable everywhere.
- We will eventually be able to bring
full autonomy to the farms, but also just understand
a lot more about what's going on,
on an inch-by-inch basis, plant-by-plant basis.
- I see a farm of the future where we have massive data
to tell us what's best from a prescriptive standpoint.
We will farm specifically to what the crop is telling us.
We can feed the world for less-
that's the value for me in the next five years and beyond.
- Could we ever really win a war against weeds,
even with a weapon like this?
- None of this is just you deploy a thing and it's finished.
You have to be really part of the environment.
It's not a war that you win,
it's an ecology that you take part in.
- So I think the bright future for me is if I take
cross-country flight at night.
And as we're flying along, I can look down
and see there's little spots of bright,
strobing light on the ground,
knowing that they're not using herbicides.
- Josh Roberts interview, take one, that was bad.
Josh Roberts, take interview.
Second sticks.
I need coffee. - Yeah, we all do.