This Endearingly Janky Raspberry Pi-Powered Coffee Maker Automates Your Morning Routine
Pseudonymous maker "petertree" has built a coffee maker — "2x more expensive and messy than one you can get on Amazon," he notes — powered by a smart plug, a peristaltic pump, and a Raspberry Pi.
"Excuse the messy setup," Peter writes of the project. "I used an INTLLAB pump, L298N driver, basic servo, and a TP-Link Kasa smart plug for this. The [Raspberry] Pi turns on the kettle via a servo arm, it then turns on the grinder via a Wi-Fi plug. And last it pumps water from the kettle into the grounds. All I have to do is walk over and flip the Aeropress that's now full into a cup and press down and I get coffee."
The project is, perhaps, not the most aesthetically pleasing — having been finished around four in the morning. "[I] still need to clean up wires," Peter notes. "I made a ground bin out of cardboard and a torn Ziploc bag. Note the copious tape holding the servo to the kettle."
It's definitely functional, however, with a few caveats about relying on the kettle's own cut-off mechanism if the servo gets stuck and issues with keeping the Aeropress in its compressed state for longer than recommended. "It turns on the kettle," Peter explains of the order of operation, "heats the water, turns on the grinder, the grounds fall into the Aeropress, it then pumps 200g water (@5.24ml/s) and all I have to do is press down the Aeropress. I pre-weighed 11g coffee."
Peter has not shared a schematic or source code but has confirmed the use of a Python library to control the TP-Link Kasa smart plug from the Raspberry Pi, with more information available on the project's Reddit thread.