A few weeks ago I had the idea of creating a light bulb that when shot with an airsoft or Nerf gun will turn off. The most difficult part of this project will be the pneumatic button but as if today I have my first prototype working.
The silicone dome was cast from Smooth On Dragon Skin 30 in a 3D printed PETG mould. I then laser cast a base and ring to sandwich the dome sealed and used some RTV sealant to help out a bit. Inside the dome is an Adafruit BMP280 barometric breakout board with all seven wires running to an Adafruit Feather. Some test code was written and when the dome is depressed, the red LED on the arduino shuts off and remains until it is reset.
Now that the prototype works, the next step is to put it into light bulb form factor. I will be using an eBay 5v 2A switching PSU to power the whole system. The board will be a purpose built board with a 3v3 logic ATMega328 running at 8MHz and a constant current LED driver for the 5W (or so) LED. The Barometric sensors will probably just be eBay specials as I can get them for under $1 soldered to a breakout and the raw BMP280 from Digikey is over $3 each. As I get parts in and work on the bulb form factor version I will make new posts detailing the progress.