[Noisy Electrons] is a maker who also likes to keep fish. He sometimes needs to travel and keep his fish fed in the meantime, so he created an automated solution to handle that for him.
The build is based around an STM32 microcontroller, paired with a MCP7940N real-time clock to keep time. The microcontroller is hooked up to a few buttons and a small display to serve as an interface, allowing the feeding times and dosage amounts to be configured right on the device. Food is distributed from a 3D printed drum with a hole in it, which is rotated via a stepper motor. Each time the drum rotates, some food falls through the hole and into the tank. Dosage amount is measured in rotations — the more times the drum rotates, the more food is delivered to the fish.
[Noisy Electron] built three of these devices for three separate tanks. Thus far, it’s been three weeks and all the fish are still alive, so we’ll take that as a vote of confidence in the build. We’ve featured some other great pet feeders over the years, too
Nice clean build, I like the positive metering with the drum vs/ some with an auger. I used to do industrial systems and we would put a sensor system of some sort to be able to make sure the drum rotated and returned to the proper position and an alarm if there was an error.
But nice job
Such devices are quite widespread and cheaply available, you don’t need to build it yourself
As a kid, I had automatic feeders that were nothing more than. A 24-hr timing motor and metal fingers that could be attached to its output shaft that would ride up a ramp to engage with the segmented ring that the daily aliquots of food would sit in. There were single and double-finger inserts so I could feed the dish 1, 2, 3, or 4x/day. Not very flexible but it kept my fish alive when I was away for long periods in the summertime 😁