Woodworking with power tools normally creates a large amount of dust. This can be bad for the humans inside, and the workshop itself, as wood particles get on the floor, walls, and whatever crevices it can float into. This process also creates a lot of noise, which is annoying and potentially bad for humans as well. YouTuber Atomic Dairy's "AudioBot," however, shows that this noise can even be used to start an air filtration system to combat the first problem.
Atomic Dairy's custom air cleaner, known as the Fanboy, runs at 1,100 cubic feet per minute and is capable of going through the shop air eight times per hour. The Fanboy is hooked up to a solid-state relay to switch its 110 VAC power supply, which is in turn controlled by an Arduino Uno.
The AudioBot's microphone picks up loud sound and automatically activates the system for two hours. Alternatively, there’s a green button along with a little RF unit that start it manually for an hour or add another hour to the run time as needed. An LCD screen displays how much filtration time remains, while a red button is provided to shut it off immediately.
Everything is encased in a nice orange box, with plexiglass shielding to keep the electronics visible yet relatively dust-free. Code for the project is available in this post and more info on the build can be seen above.