I gave my espresso machine a brain. I particularly like the animated splash screen, which starts out black and fills up in a satisfyingly glitchy way: https://github.com/flowerysong/ESPress0x20/blob/5b6b71ee653496ffb639b069b10bea96112f9484/ESPress0x20.ino#L194-L219
@flowerysong that looks so cool! What’s the brain do?
@humphrey Right now it does two things. The first one is temperature display and control. A stock Gaggia Classic uses a bimetallic thermostat, so the actual temperature when the indicator light says it's "ready to brew" can vary by something like 10 degrees. This is not ideal. Using a thermocouple to read the temperature and a PID control loop to manage the boiler gives me more insight into the actual state and more precise control over the system temp. The second is a timer tracking the brew length, which I had been using my phone's stopwatch for, which meant juggling a second device and remembering to hit two things at the beginning and end of each shot.
@humphrey In the future it may grow more capabilities, like using a load cell to monitor the output, a pressure transducer to monitor the system pressure, and a dimmer to control the pump for fancy things like preinfusion or pressure profiling. But that's the future.