Robocod
Fishbowl existence is tough. There you are, bobbing up and down in the same dull old environment, day in, day out; your view unchanging, your breakfast boringly identical every morning; that clam thing in the bottom of the tank opening and closing monotonously – goldfish can live for up to 20 years. That’s a hell of a long time to watch a clam thing for.

Two fish are in a tank. One says “How do you drive this thing?”
Indeed, fishbowl existence is so tough that several countries have banned the boring round bowls altogether. (There’s a reason that your childhood goldfish didn’t live for 20 years. You put it in an environment that bored it to death.) So this build comes with a caveat – we are worried that this particular fish is being driven from understimulus to overstimulus and back again, and that she might be prevented from making it to the full 20 years as a result. Please be kind to your fish.
What’s going on here? Over in Pittsburgh, at Carnegie Mellon University, Alex Kent and friends have widened the goldfish’s horizons, by giving it wheels. Meet the free-range fish.
Alex K, negligent fishparent, says that the speed and direction of the build is determined by the position of the fish relative to the centre of the tank. The battery lasts for five hours, and by all accounts the fish is still alive. Things are a bit jerky in this prototype build. Alex explains:
The jerking is actually caused by the Computer Vision algorithm losing track of the fish because of the reflection off of the lid, condensation on the lid, water ripples, etc.
Alex and co: before you look at more expensive solutions, try fixing a polarising filter to the camera you’re using.
All the code you’ll need to torture your own fish is available at GitHub.
Of course, Far Side fans will observe that there is nothing new under the sun.

Image from Gary Larson, The Far Side.
If you’ve got any good fish puns, let minnow in the comments.
38 comments
Richard
Sounds like a good project to do, I’ll have to mullet it over for a while.
Nigel
That sound a bit fishy to me
Richard
I guess any fin goes with a raspberry pi.
Maglyte
hmm.. could you not put tracks on it and make it into a proper fish tank? (I’ll get my coat!)
Andrew Coburn
Following on from what Maglyte said, reminds me of the classic joke: Two fish in a tank. One says to the other: “you drive, I’ll man the guns.”
If you combined the optical tracking of two fish in the tank. One’s position could control where the tank drives to, and the other fish’s position could be combined with the auto tracking nerf gun project, that this hacking crew already have already written.
Maglyte
…AndrewS, can’t decide if your idea is madness or genius.. (though I’m coming down on the side of genius)..
I’d like to pledge allegiance to our Piscean Overlords now!
Winston
So is goldfish racing a thing now?
Richard
With all that wobbling about it looks like a jellyfish. Sprry, I just codn’t resist another one. I went to an acodemy to learn these…..
Sorry. ;)
ERic
A better control system then simply turning the motor on and off would help in these situations.
wayne
I don’t want to be “that guy”, but…is that really good for the fish?
ric96
gold fish usually have a reset time of 3 seconds.
user1
research reveals that “3 second memory” of gold fish is a myth. gold fish can be trained and their memory is much higher than 3 seconds. gold fish can remember. keeping fish in a tank is cruelty! Ban fish tanks!!
fish_liker
That looks like a really stressed fish.
Dave
He’s not stressed… he’s just under pressure.
BabyGaintFish
watched video, the related videos afterwords where all of babies swimming. My mind is now split two ways… The fish are evolving thanks to technology and babies show that we can devolve back to our old aquatic ways. With this in mind, imagine our future.
Nick Murphy
I don’t want to Carp. Mm .. Fish Pi. Bet the goldfish has Haddock with this experiment, Daceing with death on the roads. I’ll stop now as I’m feeling a bit Tench but those builders must be Breaming with confidence.
ameyring
It’ll be interesting to do this with a dog, cat, bird or primate and see how they learn to position themselves to move the thing where they want.
exartemarte
Wouldn’t they drown?
ameyring
I meant if they stood on a platform that tilted in the direction of movement. Didn’t clarify that :)
DJ
Now THAT was friggin’ hilaricthyous!
Pete
Is this an E fish nt use of a Pi? … boom tish
Romilly Cocking
I’m hooked…
Iuga Marian-Silviu
Next up, fish drones with 3D movement from 3D fish position in the fishtank :)
AndrewS
I guess it puts a new twist on trying to catch a fish ;-)
Chasing Nemo.
Robert A
That moving tank is no plaice for a fish !
Randy Albright
Now they can drive themselves to school!
Randy Albright
Q: Where do fish keep their money?
A: In the river bank.
Tony
Perhaps animals are not “things” for entertainment? Perhaps they would naturally live in an interesting environment with companionship of their own species?
Bob
2 budgies sitting on a perch, one said can you smell fish?
Stijn
PWM motor speed control to regulate speed.
That way you can make the thing move more smoothly…
Hans
You could learn it to play tag …. hide and seek … Maybe the fish is a lot smarter then you think.
Great project
Tyler
Fill the tank full, removing all air and sloshing and imaging issues would be minimized.
Jim
There are probably better solutions to this, slow down the motors, waterproof camera for tracking, etc. but the only problem is that you’d /*sink*/ so much money into it that your /*goldfish*/ would become a /*bronzefish*/!
Jan Kok
They built that thing just for the halibut.
CodingWhiz100
I can’t believe how much u can do with a raspberry pi!
Wild Bill
Personally, think this is an amazing experiment. A few design changes and a little more tech on tracking devices working together with a second balancing tank that can be where you super aerate and filter before pumping into a close tank without air bubble and these little guys will pave the way for smarter aquatic animals to torment humans and cats even more… Can you image a goldfish chasing your cat for a change. Cool ideas!
Nawaz Dangra
can somebody here tell me the estimated cost and time required for this project?
Tennessee Sombrero
Carpé Diem, goldy!