Patriotic Pico - a Raspberry Pi Pico Fireworks Controller

Since the 4th of July (or Guy Faukes Day, or your country's celebration day) is coming up in a few months, I decided to get ahead of the game and make a fireworks controller to have some fun with the Raspberry Pi (and fireworks, of course).

Supplies:

Electronics:

• 1 Raspberry Pi Pico
• Several Jumper Wires
• 1 Normally Open Pushbutton
• 1 Servo
• 9V Battery for the Pico
• Battery to USB Converter for the Pico

Tools:

• 1 3D Printer
• 1 Soldering Iron
• Solder
• A few matches
• 10 large nails, about 3-4 inches long
• a lighter
• Heat Gun
• Heat-Shrink Tubing
• Computer
• Optional - Raspberry Pi 4

Products available on Sparkfun, here, and here.

These are the wish lists on Sparkfun for the electronics, and tools, respectively.

Step 1: Design

The premise of the design is this:

A match is heat-shrunk to the servo horn. After you press the light the match with the lighter, you press the button until the servo turns to the fuse, which the match lights. Then, you blow out the match and run. Fireworks explode, as your family and friends ooh and aah over the fireworks, and your workmanship.

Step 2: Enclosure Design

The enclosure is here on Github.

3D print it with these settings:

• Material: PLA
• Infill: 5%
• Supports: Everywhere
• First Layer Temp: 216°C/44°C
• Other Layers Temp: 211°C/45°C
• Layer Height: 0.12 mm

I advise you to do it now, because it takes 18 1/2 hours to print on an Ender 3 :)

Step 3: Soldering and Other Connecting

This is the electronics part...

Take your Pico and your soldering iron and solder a jumper each to GPIO22, GND, and VBUS. Then, solder a jumper to one of the pushbutton terminals.

Take a match and lay it on one horn of the servo, slip a large heat-shrink tube around it, and shrink it. The tip, and about 1 inch of the match should be showing.

Step 4: Wiring and a Little More Soldering

Grab your servo and connect the VBUS and GND pins to the red and black wires, respectively. Heat up your soldering iron at this part.

Take the GPIO22 jumper and solder it to the pushbutton terminal across from the other wire on it. Connect the other wire on the pushbutton to the servo's white wire.

Step 5: Programming

Use the code here at Github to program your Pico. (I don't know when you are reading this, but I may have both Arduino and MicroPython there, because Arduino is supporting RP2040 in the near future.)

I recommend programming your Raspberry Pi Pico with a Raspberry Pi 4 with Mu or Thonny Python installed.

Test the code. If there is any problems, do a double check. If it still doesn't work, comment and I will help as soon as I can.

Step 6: Enclosing the Controller

Get your enclosure and put the assembly in it. Put the servo through the slot in the front, and make sure it can turn freely before moving on. Test it with the button as well.

After testing, if you're ready, grab your fireworks.

Step 7: Setting Up the Controller

After your lid is finished, put it on and pop the button through. Glue it in with some hot glue on top, and test it again with the button mounted. If it works, congrats!! You have built yourself a homemade fireworks controller!

Now, refer back to the Design step's pictures with the fake fuse. Set the controller up at the end, and put the fuse in a position where it can be lit by a swiveling servo.

Then, connect your main fuse, however you can, to all the fireworks' fuses. Keep in mind, they will all be lit at the same time. The linked main fuse roll was 10 feet. Use enough that you feel safe not running, but not too much, so it won't burn too long and blow out on the way. Remember, the best way is the safest way.

Disclaimer: I am not responsible for any injuries, burns, or deaths this device might cause.

Step 8: Updates to Come

I am currently working on a automatic lighting system with an arc to light the match. I may also add a camera that runs when you push the big button. I will definitely update the igniter too (tantalum cap anyone??).

Step 9: Finishing Up

Have fun! Be careful too, because this can certainly malfunction.

Now, sit back, brew a coffee, and stay safe and healthy.

Until next time,

Merry Making from g3holliday