As part of Professor's Gallagher's Physical Computing Class, our class was tasked with an assistive technology project to aid students in the Campus School at Boston College. After I spoke with the Assistive Technology Specialist at the Campus School, the idea for a button-controlled pom-pom was brought up. Through the power of CircuitPython and the Arduino Nano RP2040, students can make a pom-pom shake and play BC's fight song through the push of a button!

Supplies

You will need:

Breadboard
Arduino Nano RP2040 w/ CircuitPython installed
Female End of an Audio Jack
Power Cord
Servo
Popsicle Stick
1/8'' inch Baltic Wood
Laser Cutter
Speaker
LED strip w/ alligator clips attached
6 male-to-male jumper wires
3 female-to-female jumper wires
Double-sided Tape
Soldering Kit
Hot Glue
Paint (Red, Blue, Gold, Yellow, Black)
USB-C Cable
Power Box
2 Alligator Clips
Any Machine that can cut through plastic
Wood Glue
Wire stripper
Scissors
Electrical Tape

Step 1: Cut Box

In order to house all the wiring, and make the project look aesthetically pleasing, I had to cut out a box using a Trotec Laser Cutter. I used a website called MakerCase.com, where I made the box nine inches wide, and the height/length both 4 inches. Then, I converted the svg file into Adobe Illustrator, where I made sure the outlines were fit for cutting. I had to cut a few holes on the top of the box in order to make sure that the servo and the audio jack could come out of the box. In addition, I created slits on the sides of the box so the top component could just slide in and out in order to make wiring a lot easier. Professor Gallaugher has a great video online going into detail on how to create a box: video.

After all the parts of the box were cut up, it was time to paint! I mixed red, blue, and yellow together to create a maroon color and I mixed gold and yellow together so it would represent Boston College's color. In addition, I engraved an eagle and a "Go Eags!!!" onto my box, so I also painted that as well. After letting the paint dry, I glued the components of the box together, except for the top.

And now we have our box!

Step 2: Solder

For the button to work, I had to solder the female end of the audio jack to the male-female jumper wires. The audio jack had two wires; so I needed to solder each wire to a jumper wire. I used a wire stripper to take off about .5 mm off each wire in order to make soldering easier. I then used the soldering kit and heated it up to 700 F, and used the solder wire to connect the wire of the audio jack to the male end of a jumper wire. I did the same for the other wire of the audio jack.

There are tons of videos on Youtube to facilitate the soldering process.

After the two were connected, I wrapped electrical tape around it. You can also use a heat shrink tube and heat gun, but I did not have those supplies readily available. Finally, I connected the female end to the male end of the audio jack together.

You should now have a working button!

Step 3: The Servo

I decided to use a servo to "shake" the pom-pom. There are alternatives such as solenoids or a DC motor could move the pom-pom around as well.

First, I cut off the handle of the pom pom using a cutting machine to hot glue to popsicle stick to the base of the pom pom. Next, I hot glued the servo to the popsicle stick as depicted in the images above. The pom pom, servo, and the popsicle stick should all be secured at this point. However, for extra security, I screwed the arm of the servo to the actual servo.

Finally, I hot glued the servo to the top of the box. The servo component of the build should all be completed!

Step 4: Wiring

The wiring for this project included a lot of components. For the servo, I used board D3. For the speaker, I used board D4. For the button, I used board D2. Finally, I used board D5 for the neopixel strip. I connected the components to GND and the 3.3 V pinouts of the breadboard. The image above shows the overall wiring of the entire project.