This project started as an Arduino PID controller for my coffee machine and gradually became a lot more. Read about it here. See a video of the machine in action here.
Presently there is just a controller PCB and firmware. In time I plan to build a front panel PCB as well. The board is designed to mount neatly in a Gaggia Baby machine but there is scope for other layouts for different machines. The circuit diagram would work with pretty much all machines with some modifications to the firmware.
hardware/controller contains EAGLE CAD files for the controller PCB which is an Arduino Nano shield.
hardware/schematics contains PDFs of the schematics for release versions of the controller. Saves hacing to have EAGLE installed and also gives past versions.
firmware/controller contains the Arduino source code.
hardware/controller/DesignNotes.txt contains a lot of useful information as well as notes about what needs doing next.
The present revision of my controller is 2.0, but I already know of some things I would like to change in 2.1. DesignNotes.txt documents these.