CatBot animal feeder
By Andrew Gregory. Posted
If you like cats, and you want to be alerted whenever a cat wanders into your garden, then we have the project for you. CatBot is a notification system for stray cat sightings. It’s a brilliant example of a project that takes a minimal amount of hardware, adds open-source services, and just works.
CatBot is built using two Raspberry Pi boards: the first, a Raspberry Pi Zero, hosts a Raspberry Pi Camera Module 2 and a Flask server, which sends images to a Raspberry Pi 5 for processing. The Raspberry Pi 5 is a much more powerful machine, and so that’s where the clever stuff happens: it runs a computer vision model, which determines whether the cat-shaped collection of pixels is a cat. If it’s a cat, the Raspberry Pi 5 can send photos to Michael’s phone via a Twillo client (as an MMS message, sent to Michael’s phone number, not an email).
“I used Raspberry Pi because I was recently working with Raspberry Pi and cameras for another project, a digital sensor for a film camera,” says Michael. “Although there are definitely simpler solutions with cheaper microcontrollers, I find it valuable to start with techniques I know rather than going down rabbit holes of learning new tools. I used two separate boards because Raspberry Pi 5 is my home server and NAS, which I did not want to mount on the kitchen window.”
But there’s a catch: the food that Michael was leaving out for the cats was also attracting birds, for which cat food is potentially unhealthy, so he needed to find a way of identifying birds and scaring them away. He eventually settled on a minimal solution that just – only just – qualifies for the label of ‘robot’: an actuator (a Tower Pro micro servo) connected to a chopstick that taps on the window to scare the birds away. If Raspberry Pi 5 detects a bird, it sends a request to Raspberry Pi Zero to activate the servo.

“Defining ‘robot’ is hard to pin down and frequently leads to disagreement among roboticists,” says Michael. “I believe that a robot is any physical thing with sensors and actuators. While some definitions require autonomy, that excludes arguably robotic things like human-piloted mecha or heavy industrial equipment. Relaxing the requirement of autonomy frames robots as tools that complement rather than supplant our abilities, which I find valuable in the current hype wave of AI and ML.
“There are commercial products that do similar things, like the Bird Buddy or pet-oriented indoor security cameras. By the time that I could hack those to get the functionality I wanted, I might as well have started with open-source tools.”

“My favorite projects include Blossom, an open-source robot platform that I developed during my PhD, and the Leica MPi, a swappable digital sensor for a Leica film camera. I’m currently taking a sabbatical at the Recurse Center, a programming retreat in New York, where I am exploring alternative HCI hardware and brushing up on AIML for robotics.”
Features Editor Andrew trawls the internet for Cool Stuff while keeping the magazine running smoothly.
Subscribe to Raspberry Pi Official Magazine
Save up to 37% off the cover price and get a FREE Raspberry Pi Pico 2 W with a subscription to Raspberry Pi Official Magazine.
More articles
Make your RAM go further – Raspberry Pi OS memory optimisation tips
In issue 164 of Raspberry Pi Official Magazine we have been playing around with the new Raspberry Pi 5 1GB RAM. While the RAM shortage caused by the demands of AI infrastructure is annoying beyond belief, this has been a great chance for us to really get to grips with RAM. Generating images in Stable […]
Read more →
Mighty Projects – 1GB Computer in Raspberry Pi Official Magazine 164
It’s normal for computers to get faster and more pwerful, but the new-ish Raspberry Pi 5 1GB is a step in the other direction: it has all the processing power and the same GPIO pins of its more costly siblings, but with only 1GB of RAM it’s at a price that’s friendlier on the wallet […]
Read more →
Win one of five 256GB Raspberry Pi Flash Drives
If you’ve been around long enough, you know that every Raspberry Pi accessory is top quality, and the latest Flash Drive is no different. Fancy a big one? We have five up for grabs, and you can enter below… Win 1 of 5 256GB Raspberry Pi Flash Drives
Read more →