Watch MIT’s Hypnotic Robot Fish Swim a Coral Reef

[Narrator] You're looking at a brand new species of fish.

It's not super fast, but hey, you're not

super fast under water, either.

The thing is, this fish isn't made

of flesh, but electronics.

It's a clever new remote controlled robot from MIT.

This is how it sees the world.

And boy, does it have a whole lot to teach us.

You've never seen a robot move like this before.

It's known as a soft robot because, well, it's soft.

A traditional robot uses electric motors

called actuators to move.

This robo-fish on the other hand,

uses two opposing chambers in the tail,

which a pump fills with water.

And all you do, is you cycle the water

back and forth, and that causes the

undulation and the wiggling of the soft tail.

And by controlling that flow of water,

we can do turning, we can go straight,

and

we can propulse forward.

[Narrator] Thus, the robot moves

like an actual fish, and it also floats like one.

Real fish control their buoyancy,

using a gas filled organ, called a swim bladder.

We have a buoyancy unit, that basically

compresses a cylinder filled with air,

and decompresses, and by that action,

we also changed the buoyancy of the robot.

[Narrator] This is important, both for real

and robot fish, because it saves a lot of energy.

Instead of having to correct up and down,

to maintain a position at a certain depth,

you can use gas to do it automatically.

Now, a big challenge for underwater robots is communication.

Radio waves can really only travel

a few centimeters under water,

a few meters max, if you put a lot

of energy into boosting the signal strength.

The divers control this robot fish with

acoustic signals, which travel for much longer,

and use much less energy.

We sent this acoustic wave across,

and the fish then, encodes those signals,

and reads out bits that it then identifies

to be the state of the fish.

[Narrator] So you've got yourself a rather

hypnotic remote controlled fish.

What exactly can you do with it?

For one, turn it into a spy.

What we were able to observe in our

initial study is that other fish

would sometimes swim alongside,

a little curious to see what's going on.

Other times, they were not at all

distracted by anything, while us, as divers,

if we would get close to those fish,

they would just swim away instantaneously.

[Narrator] That could mean using the robot

to surveil coral reefs, to determine their health.

In particular, the robot could one day use

machine vision to lock onto a fish, and follow it around.

Other uses of our system could be

to make a swarm or whole network of these

soft robotic fish to monitor

the environments, to monitor pollution

of the ocean and to see how the ocean

might be affected by human factors.

[Narrator] And hey, if Nemo decides to get lost again,

MIT will have an eye out.