Finishing up a Halloween prop - based on some designs I found online, a “Monster in a Box” (we went with Dragon in a Box). Runs on an Arduino Uno (probably could have used a Nano but didn’t have an extra around).
It plays a sleeping/growling dragon soundtrack through a large bookshelf speaker while idle but when a motion sensor detects trick or treaters it blasts a dragon roaring soundtrack, rattles the box lid with a windshield wiper motor, shoots some fog from inside and flashes some lights.
We’ll see how it goes once out in the wild. I’m not very knowledgeable about coding so AI did most of that for me but we’ve done quite a bit of testing and it should work ok. Maybe V2.0 will be better next year and I’ll add some air solenoids for more responsive kick as well as blow air at the trick or treaters.
We made the box with some old pallet wood we had and the kids loved painting some warning signs and stuff with some stencils we 3D printed and adding a chain and a 3D printed old fashioned lock.
Then I hit it with an oxy acetylene torch with a heavy carburizing flame to char the box in strategic locations and add a lot of soot/smoke.
It was a really fun project with the kids; they’re excited and maybe got to learn a few things along the way and hopefully we capture some good scares on the Ring.
The guts: Top to bottom, left to right: relay board, breadboard with sound card, Uno, amplifier, amp power supply, Xbox power supply for the windshield wiper motor (actually pretty decent capability)