foginator001jpg.jpg


Halloween has always been one of my favorite holidays, so much so that I founded a business that makes professional-grade props and controllers for Haunted Houses. This naturally led to Element14 asking me to create a couple of projects that were easy enough for the community to follow along and replicate the project at home. For my second project, I am going to be creating a automated Fog Machine controller that utilizes a Raspberry Pi, and the new Sense Hat.

The Concept


foginator-Flow-Chart.jpg


The basis of this project is to utilize the all new Sense Hat from the Raspberry Pi Foundation to work in conjunction with the Raspberry Pi and a Relay to activate a fog machine when guest trigger a motion sensor. For those of you who might not follow new Raspberry Pi products as myself, the Sense Hat features an array of environment sensors that relay data back to the Raspberry Pi. To be honest, I struggled to figure out how I would tie the Sense Hat back into this project, and after a few conversations with friends I think I have come up with an idea.


I am going to utilize the Sense HatSense Hat to log data about the environmental conditions on Halloween Night and use the fog machine triggers to log what I will call a “Trick or Treat” event. When the night is over, I will compile the data and try to determine if swings in temperature, humidity, or air pressure correlates to a rise or fall in trick or treat events.


senshat.jpg


I will also utilize a few more of the Raspberry Pi’s GPIO pins to trigger some special effects lighting (NeoPixels), and will play an array of spooky ambient sounds, halloween-themed music, and (if time allows) audio events when the fog machine is triggered. One final bonus feature will be to integrate some form of remote notification when a trick or treat event occurs.

This project will progress a little faster than my Trick or Trivia Candy Dispenser project, mostly because I am building both at the same time. I purposely kept this project a little more simple for this reason. You will also note that I have chosen to use an off-the-shelf relay module this time instead of building my own as I will be doing in my other project. This is both in the spirit of saving some time, but as well to illustrate that there is alternative solutions that are ok to use as well.


The Hardware



Newark Part No.

Notes

Qty

Manufacturer / Description

38Y646738Y6467

RPi

1

RASPBERRY PI 2, MODEL B

38Y647038Y6470

SD Card

1

RASPBERRY PI 8GB NOOBS MICRO SD CARD

44W493244W4932

PSU

1

USB PORT POWER SUPPLY 5V, 1A

06W104906W1049

USB Cable

1

USB A PLUG TO MICRO USB B PLUG

53W628553W6285

WiFi Dongle

1

USB WIFI MODULE

18J555818J5558

Home Pir Sensor

1

PIR MOTION SENSOR

40P118440P1184

Speaker

1

SPEAKER, 20 kHz, 8OHM, 4W

26Y845826Y8458

Fog Coloring Rings

1

NEOPIXEL RING - 16 X WS2812

26Y851226Y8512

Ambient LEDs

1

NEOPIXEL 8MM THROUGH HOLE LED

26Y852826Y8528

AMbient LEDs

1

NEOPIXEL 5MM THROUGH HOLE LED

26Y846026Y8460

Mood LEDs

1

NEOPIXEL DIGITAL RGB 1M 144LED BLACK

34C109234C1092

PSU Vreg

1

LM7805 LINEAR VOLTAGE REGULATOR, 5V, TO-220-3

58K379658K3796

PSU LED Resistor

1

METAL FILM RESISTOR, 1KOHM, 250mW, 1%

17F216517F2165

PSU Filter Cap

1

CERAMIC CAPACITOR 0.1UF, 50V, X7R, 20%

69K794969K7949

PSU Filter Cap

1

ELECTROLYTIC CAPACITOR 47UF, 50V, 20%

69K790769K7907

PSU Filter Cap

1

ELECTROLYTIC CAPACITOR 100UF, 50V, 20%

14N941814N9418

PSU LED

1

LED, RED, T-1 3/4 (5MM), 2.8MCD, 650NM

49Y756949Y7569RPi Sense Hat1Raspberry Pi Sense HAT




MCM Part No.

Notes

Qty

Manufacturer / Description

83-14732

Relay Module

1

TinkerKit Relay Module

555-19400

Fog Machine

1

Fog Machine Hurricane 901

28-12812

Audio Amp

1

Audio Amplifier Kit 2 X 5W RMS

83-15748

Logic Level Converter

1

8 Channel Logic Level Converter

21-15178

Project Enclosure

1

ABS Case Gray - 5-5/8" x 3-1/8" x 1-3/16"



As you can see, in this project I am using a fairly high-end fog-machine. Any fog machine will work as long as it has a wired remote. You can use a $19.99 200W fog machine from a party store, or a $699 fog machine from a professional event supply shop as long as it has a wired remote with a push button. Additionally, you will need to purchase some form of water-based fog juice. There are hundreds of brands out there, and all will work just fine, but some of the more professional brands like Froggy’s Fog will have better results. You could even make your own fog juice and I will include a recipe for that in a later blog post.


The ADJ 1300w Fog Machine In Action. Video courtesy ADJ Lighting.


In addition to the parts listed above, you will need a few yards of 3-conductor wire (4-wire phone cable works well), or 100 feet or more of single conductor wire that will need to be paired up for the NeoPixel and Audio components. Finally, you will need a 3.5mm audio extension cable, an ethernet patch cable, or a wifi router. A soldering iron will also be needed to assemble parts of the kit. Having some heat shrink tubing, electrical tape, zip ties, and a hot glue gun on hand would be advised as well.

If you have any questions, suggestions, or comments in general, please feel free to leave them below, or by sending me a private message here at Element14. If anyone chooses to follow along at home and build their own Trick or Trivia Candy Dispenser, please post photos, and even blog post if you can as I am very excited to see your work!

I will be posting an update every Friday with the project wrapping up on October 16th. I have taken the liberty of laying out each of the weekly milestones below.


Win this Kit and Build-A-Long


  1. Project Introduction
  2. Fog Controller Hardware and Test
  3. Environment Sensing Coding & Testing
  4. Ambient Audio Hardware and Coding
  5. Lighting Coding and Testing
  6. October 16th -  Final Assembly and Testing
  7. October 23th - Project Wrap-up