There's an amusing joke about some fish in a tank, idly wondering how they drive it. Build them an FOV (fish-operated vehicle), however, and it seems they do more than idly wonder - they actually drive the thing to actively seek out food. At least, that’s the conclusion of a paper in the February edition of Behavioural Brain Research, available on Science Direct (opens in new tab) and reported on the Raspberry Pi blog (opens in new tab). Why that blog? Well, the computational brains behind the FOV is a Raspberry Pi (opens in new tab) 3B+.
Created by researchers at Ben-Gurion University, Israel, the FOV consists of a life-support chamber (an aquarium half-full of water) towered over by a mast. On this mast are cameras, looking down at the fish below, and connected to the Pi 3 running motion detection (opens in new tab) software. Beneath the chassis are wheels, allowing the whole assembly to trundle around. There's also a LIDAR sensor that reads the FOV’s surroundings, preventing the piscine perambulators from crashing.
When a fish swims near one of the four tank walls, the camera picks up the movement, and the Pi directs the wheels to move the FOV in the appropriate direction. Fish being what they are, the movement can be a little erratic, but they soon learn to guide the FOV toward a pink patch on the wall, which nets them a tasty reward.
Decoy patches in different colors didn’t fox the fish, who always homed in on the pink after just a few days’ practice. The researchers’ video also shows the FOV moving around outside, but doesn’t mention whether or not this was an escape attempt, nor whether the FOV continues to roll around the streets of Beersheva, looking for pink things to run into in the hope of getting treats.