I tend to roll my own with rp-picos for no good reason other than they're easy.
1) Wattmeter for a toy solar installation - broadcasts a UDP packet every few seconds, which I then record into a staging JSON log that gets ingested into DuckDB.
2) Little pico-w wifi temperature sensor that feeds into the raspberry pi zero that controls my boiler.
The boiler control is the fun one but it's not entirely embedded stuff. Runs a little control loop that turns down the boiler modulation based upon the difference between target and current temperature. Improves operating efficiency by a fair bit and reduces temperature swings. Makes me wish residential HVAC systems were more sophisticated - these are things any good industrial control system can do.
3) Made an "ok to wake" light for my son -- added a controllable LED strip to his clock with a pico-w in it that changes from orange to multicolored at 6:30am as a non-intrusive "yes, you can come bug your parents" signal.)
Oh my gosh that is totally charming! The clock i repurposed for ours has a bit too much of a "this belongs in an office" vibe. Fun to see how different the same idea ends up. I had the same concern about kid-proofing, but I took the route of putting mine on the wifi and using NTP instead of an RTC. (Because it knows the date, it plays different patterns on holidays and on his birthday.)
1) Wattmeter for a toy solar installation - broadcasts a UDP packet every few seconds, which I then record into a staging JSON log that gets ingested into DuckDB.
2) Little pico-w wifi temperature sensor that feeds into the raspberry pi zero that controls my boiler.
Thread about the boiler: https://hachyderm.io/deck/@dave_andersen/111579107766689328
github with some really crappy rust code: https://github.com/dave-andersen/boiler
The boiler control is the fun one but it's not entirely embedded stuff. Runs a little control loop that turns down the boiler modulation based upon the difference between target and current temperature. Improves operating efficiency by a fair bit and reduces temperature swings. Makes me wish residential HVAC systems were more sophisticated - these are things any good industrial control system can do.
3) Made an "ok to wake" light for my son -- added a controllable LED strip to his clock with a pico-w in it that changes from orange to multicolored at 6:30am as a non-intrusive "yes, you can come bug your parents" signal.)
https://hachyderm.io/deck/@dave_andersen/112091315519210298