This is apparently the only printable auto cat feeder that is legit practical, reliable, inexpensive and easy to build from readily available parts. All you need is the pico W and servo and some screws and the printed parts, no hard to source gear motors or anything. No extra parts like screens, no issues with the strength or reliability of parts or printability of parts or anything.
This is to a significant degree about the exploration and illustration of a different paradigm for "livingry". If you look closely at the bad reviews on Amazon for instance, you can see that planned obsolescence etc. is no conspiracy theory, and remember very few people come back after six months to complain when stuff breaks so they are just the tip of the iceberg.
If anything does break here it can be replaced or repaired.
This is not about this exact design as it stands, people are supposed to fork, improve and remix it, like the open source beer recipe.
There is a remarkable variety of features people seem to want in something so simple, so I started with the fundamentals: reliability and low cost.
Maybe someone can add a camera or voice clip replay or whatever.
This seems to be quite reliable now, after I overhauled the micropython firmware. I've tested it for 2 weeks now with no issues at all.
It can also be accessed over adafuit.io or other providers through MQTT. You get status updates and can tell it to dispense food from anywhere at any time through the internet.
You program as many feeding times as you want through the wifi interface, just enter the ip address of the device in your web browser (use a wifi network scanner like Fing to see what the ip address is).
It has a usable kibble capacity of about 1 liter. This could be increased by making the drum longer.
To be honest there are competing forces and this actual design could use some further testing (don't let that scare you off, it's good as far as I can tell), but I think it's off to an excellent start as the design is inherently clog proof, the electronics are well tested on a hardware level (standard, widely used component), mechanically simple, plenty strong etc.
It is modular and easy to interface to so it can be used for training or even in research to train or do reinforcement.
The scoop size is adjustable, you can use a larger or smaller scoop. I found I had no problem getting 3 to 15 kibbles dispensed at a time. A small number is good for training, larger is a little easier for normal feeding because it's a bit less wear and tear on the servo.
I recommend the full metal gear mg995 or similar servos from aliexpress, they are a pretty good deal and come with the servo horn and screws.
You can use standard M3 and M2 screws but I like the self tapping kind.
There is a manual and a bill of materials (parts list) on the google drive, also information about wiring and setup and assembly.
https://drive.google.com/drive/folders/1q_JFGuSaOgExdBtov9I0X2NE5eZC3rMr?usp=drive_link
This cults 3d thing is so you can kick me a beer. Please do if you can because I'm not a wealthy man.
Total cost is maybe $23 USD:
$8 for filament
$7 for pico W
$5 for servo.
-a little extra for screws or whatever.
Most people have usb adapters and micro usb cables kicking around so that hardly counts.
Export the stl files from the fusion file, that's the source code. I don't post STL files because they are impractical to modify and I have to keep updating them which I never have time to do so you get all these old files kicking around and it's a mess.