Step up your decor game this year with a motion-sensitive fog machine. This guide will show you how to hack a standard-issue Halloween-store fog machine to add lights and reactivity, and also how to use Adafruit IO to control your lights and fog from your smart phone -- from anywhere in the world! 

Make your yard dragon breathe its fiery foggy breath whenever trick-or-treaters happen by. This project will level up your Haunted House with jump-scare fun and gorgeous thick, luscious fog. 

Skill Level

This project is for intermediate/advanced makers. It has some fairly tricky soldering work using a perma-proto breadboard and a few tiny wires that require a confident touch. There are a lot of pieces to account for, so give yourself some time to sort it all out. 

The good news is, the coding is fairly easy using Adafruit IO and Wippersnapper. Use the handy dropdown menus or blockly blocks to design and customize your user experience.

Parts

The QT Py Pico is a workhorse of a board at an inexpensive price. It's one of my favorites. ESP32 technology works seamlessly over WiFi to enable all kinds of IoT shennanigans.

This little board will replace the 12v battery inside the fog machine's RF remote so your effects will last all night long.

The relays are what make the magic happen for this project. A relay is like an automatic switch. It lets a small electrical signal turn on or off something bigger, like a light or motor, without the two being directly connected. Think of it like using a remote to open a garage door—the small button press (the low-power signal) triggers the big motor (the high-power part) to lift the door.

We'll be using the relays to "press" the buttons on the fog machine's RF remote control. You'll need two of them for this project.

The PIR sensor is the trigger. Place it where people will walk by to start your lights and fog.

You'll also want some pixels for the light effect. Choose the right type for your project. I like the 60/m tape because it's versatile and flexible, but sometimes you want high-density pixels or one of our NeoPixel rings or jewels. Shop around, Adafrruit hast so many fun form factors. 

I also used:

• Alien Tape (spoooky!)
• A plastic box enclosure
• A fog hose extension kit from Home Depot
• Black duct tape

Tools

• Soldering iron & accessories
• Hot glue gun
• Tiny screwdriver
• Dremel