[moth whirring like helicopter] ["Night on Bald Mountain" by Mussorgsky] NARRATOR: A moth's antennae are an evolutionary masterpiece of smelling.

They can pick up on the faintest of scents, like the alluring bouquet of a potential lady friend miles and miles away.

Now imagine if we could harness that power to help people like, say, after a disaster.

We could detect gas leaks and chemicals we really shouldn't smell ourselves, and possibly save some lives in the process.

And that is All Science.

No Fiction.

[whimsical music] [lamp clicks] Melanie Anderson is a jack-of-all-trades kind of scientist.

MELANIE: So I do a little bit of everything.

Electronics, coding, hardware design, biology.

NARRATOR: Add to that list moth wrangling.

MELANIE: There it is.

NARRATOR: This moth's antennae have a cyborg destiny aboard a new kind of drone called [energetic rock music] the Smellicopter.

Biology can detect chemicals at a level that far exceeds anything that's synthetic, not by a factor of a thousand or 10,000 or even a million.

Factors even greater than that.

So we use the extreme sensitivity of odor detection in living systems and asked how could we integrate it into synthetic systems?

NARRATOR: Daniel asked Melanie Anderson this question, and she's gotten her PhD answering it.

I tell people moth antenna, and they're like, "What does MOTH stand for?"

And I'm like, no, no, no.

The insect.

We actually use a live, biologic component of the moth, the antenna, and we put it on an electrical circuit to read signals from it.

It does take some hand-eye coordination.

NARRATOR: The antenna is hollow, just roomy enough for the hairlike wire.

MELANIE: Okay.

NARRATOR: So how does this all work?

When the month antenna reacts to certain odors, Smellicopter picks up faint electrical signals running between the two wires.

MELANIE: So there we have the signal from the antenna.

Right now it's pretty stable because it's just reacting to what's in the air right now, which is a little bit of everything, especially if I've just showered, then sometimes it'll react to like my shampoo or conditioner.

NARRATOR: Some moths eat flower nectar, so their antenna are highly tuned to those smells.

MELANIE: In this pipette, there's a small piece of filter paper.

And on that filter paper is some floral scent.

So I can take this [pipette puffs] and I just puff it.

[pipette puffs] And if I puff it on the antenna, then you get a signal.

NARRATOR: Electroantennogram odor sensors like this have been around for a while, but mounting it on a drone for use in disaster areas?

That's new.

[drone revs] MELANIE: You could have it in a chemical plant to be able to survey that area and find the source of an odor leak or a gas leak very quickly before it gets out of hand.

[searchers yelling] It can replace search dogs or search and rescue workers in dangerous situations.

So it can really save lives.

NARRATOR: And it only happens by bringing the natural and mechanical worlds together.

So robotics, passive aerodynamics, biology, neuroscience, insect culture.

Not bad.

NARRATOR: And yep, getting from moth to disaster-ready drone [drone whirring] is as difficult as it sounds.

["Sous Le Dome Epais" by Delibes] MELANIE: I've crashed these drones many, many times and I've barely broken any components, just a couple propellers here and there.

[dial clicks] NARRATOR: This prototype is most definitely designed for more controlled conditions.

[drone beeping] MELANIE: Let's try that again.

NARRATOR: But it's not just whether Smellicopter is stable in the breeze.

MELANIE: Hopefully this one will last a little bit longer.

NARRATOR: Finding the source of an odor is much more complicated.

MELANIE: Good.

NARRATOR: And Anderson and her project partner Joseph Sullivan have once again turned to moths to inspire how the drone flies.

MELANIE: So the moths, when they smell odor, and they want to find the source of that odor, they will surge upwind.

And then when they lose the odor, like if the winds shift or they got a little off course, then they cast back and forth crosswind until they find the odor again.

And then they surge upwind again.

MELANIE: I'm just gonna put this here.

NARRATOR: This time, they put the perfumey swab at the head of the wind tunnel.

[drone whirring] MELANIE: So let me just raise the altitude a teensy bit.

Okay, and now we're gonna go.

NARRATOR: Smellicopter flies back and forth, searching for the trail.

MELANIE: There it is.

NARRATOR: It locks in and surges towards the scent.

MELANIE: That time it went straight to the source.

It had a lot of hits right at that last surge.

JOSEPH: Yeah, I see that.

MELANIE: So it kept on going back and forth.

JOSEPH: Peak, peak, peak, peak.

NARRATOR: And if gas leaks, buried disaster victims, and explosive devices all smelled like flowers, Smellicopter would be in business, but they don't.

And that's the next big step in Smellicopter's evolution.

[door scrapes] We are working towards genetically engineering the moth antenna so that they can sense different chemicals, like amplify the antenna's sensitivity to things like bomb scents, and then kind of remove the sensitivity to things that we don't want, like the floral scent and the moth pheromone.

[drone whirring] NARRATOR: Smellicopter hovers at the intersection of emerging technologies, specifically robotics and gene editing.

And it also offers a glimpse of what could be possible if you added artificial intelligence into the mix.

TOM: There are many cells in the antennal circuit coming into the animal, each one signaling different chemicals.

So can we combine gene editing device technology and AI to make a sommelier?

[laughs] NARRATOR: And if we could make an artificial sensor that sophisticated, there's no limit to where our new noses could take us next.

[energetic music] NARRATOR: No, no, no, no, no, no.

MELANIE: Come on, let go.

You don't wanna be on me, dude.

NARRATOR: OPB sustaining members and supporters are the wind beneath our mothy wings, and we couldn't make any of our great shows and series without your support.

Check us out online and make a gift today.

[wind rushing]