As a (former) cat owner for many years, this project arose from of my increasing dislike with the time it took to clean and maintain the pet drinking fountain I had. I wanted to return to a standard water bowl again and have it automatically filled with water:

• quick to clean
• no need to purchase filters
• smaller volumes of water meant fewer worries of water stagnating
• push notifications sent to my phone

The Fusion 360 file is included. I printed the spout in ABS in three parts so I could solvent weld them together and then vapour smooth them to be water proof. The light ring was printed in a transparent PLA. While the base could be printed (assuming your print bed is large enough) I opted to make it out of plywood and a 1:1 paper template is included.

It's worth mentioning that I made this project around 2012 which is why the NRF24L01 module is used for communication (the first ESP8266 was released a few years later). If I were redeploying this again today I would opt for a single ESP32 board and set it up for MQTT.

Like most UK bathrooms I didn't have a convenient socket nearby, so, while the fountain resided next to my bathroom sink (plumbed into the cold water line), the circuit and power supply were in an adjacent room; the fountain was connected by an ethernet cable (hence the RJ45 adapters) and the solenoid valve was connected using 2 core speaker wire.

The arduino sketch is set up as a finite-state machine with two primary inputs; one to detect if the bowl is present and another to detect if the bowl contains water. Two secondary inputs are available for setup and testing; one allows to you set the "water filling time" at the fountain and the other is used to test connectivity between the NRF24 modules.

Short demo video HERE.