Share your electronics projects! (arduino/pi/beaglebone/whatever)

[Askel]

Modern microcontrollers and complete sub assemblies have put hardware hacking within reach of even computer science duffers like me.  However I have a bad habit of coming up with a "Good Idea", acquiring the parts for such, and then either never starting it or getting it just working enough to see that it works, but not implemented enough to be regularly usable.   

So, post up what you're up to.  Maybe we can all draw some inspiration to get our projects done and help each other out along the way.   

Current project. This is an iteration on something I already did for school years ago.  We put a Pi with an IR temperature sensor on a drone and wired it up to the pixhawk autopilot to pull telemetry logs. We were able to make maps of the temperature on the ground.  Neat, but the limited FOV for the temperature sensor meant a lot of flying to get a complete map of even a small area. 

So, next iteration is putting the sensor on a 2 axis gimbal. And since "lidar lite" sensors are pretty reasonable, slap one of those on there too.   End result, I hope to be able to build 3d point clouds of spaces mapping the surface temperatures detected.   Then I can do cool stuff like map the heat loss inside and outside my house to see where I need to improve insulation.  No plan to put it on the drone right now, mainly because I don't have a good application for it, but also because the limited distance capabilities of the cheap lidar sensors mean you'd have to fly very low....   

[Artem_F]

I made several things with Arduino, but the most useful one is, probably, the DIY welding station for e-bike batteries. One needs an Arduino with a screen attached, a potentiometer, and a 5V relay board attached to a bike starter relay + a standard 12V automobile battery. The potentiometer is used to set up the duration of the welding pulse. One has to start with something short and then increase the duration to get a solid weld and not to burn through the battery's wall.
Overall, I made four 36V x 10 Ah batteries, which we've been using on our 3 DIY  e-bikes (I showed two of them in another thread a while ago).

Another thing I made was an injector opening box, which I used to clean the injectors of my Chevy Lumina: depending on the number of times the button was pressed, the box sends a pulse of 1ms, 10ms, and so on. It worked pretty well in combination with a can of pressurized carb cleaner.

As for the fun projects, I made 3x3 LED cube and stuff like that.

[DoingMe]

My most recent project used an ESP8266 and a CC1101 to have my Home Assistant control the old ceiling fan in my family room by sending an RF signal to the fan.

What I wanted was to have the ceiling fan come on at low speed when the temperature in the room rose above a certain level (i.e., the pellet stove was on and heating).

A detailed write-up is here:
https://homeautomation.geiserweb.com/index.php/2024/03/21/controlling-a-hampton-bay-ceiling-fan-with-home-assistant/

I have 3d printed a box to put it all in, but have not yet gotten that assembled.  I also will want to try my best to decode the light intensity signals that the remote sends ... not because I intend to actually use them, but because it would be a satisfying puzzle to solve.

Cheers,
Wayne.