Neon Notes is a simple dodecahedron-shaped instrument running off of a simple Arduino sketch. It is a great way for beginners to become familiar with Arduino, laser cutting, and 3D printing. The three buttons correspond to different notes, and you use a force-sensitive resistor to bend the pitch. To begin, download the following files:
You will need the following materials:
- Arduino UNO
- 24x12 3" Acrylic sheet (color of your choice)
- #4-40 Machine Screws and Nuts
- 10k Ohms Resistors
- LM386 Audio Power Amplifier IC
- Force sensitive resistor
- Arcade switches (buttons)
- 3.5" Headphone Jack
- 9V Battery
- Arduino-USB cable and Arduino Power Supply cable
- Various resistors, capacitors etc.
And the following tools:
- Soldering Iron
- Laser Cutter and 3D Printer
- Wire cutters and wire strippers
- Computer with autoCAD and 3D imaging software
Step 1: 3D Printing
First 3D print the joint files found on the Thingiverse link given above. Feel free to scale to your liking, but keep in mind they must fit the pentagonal sides later.
Step 2: Solder Your Circuit and Upload the Sketch
Solder your circuit according to the schematics above. Experiment with resistors after uploading the sketch into Arduino UNO, it takes a while to get the hang of the pressure-sensitive resistor. In addition, you could choose any potentiometer-like resistor in place of the pressure-sensitive resistor to act as the pitch bend. Don't solder any buttons or amplifiers yet!
Step 3: Laser Cut Your Acrylic
Using the CAD file from the Thingiverse link linked above, draw holes according to the size of each of your inputs (buttons, speaker, headphone jack, switch etc.), searching up datasheets where necessary. Then laser cut 12 pentagons with the appropriate amount of holes.
Step 4: Assemble Your Dodecahedron
Assemble your dodecahedron with your previously printed joints and the #4-40 Machine Screws and Bolts. Keep an electric screwdriver handy for maximum productivity!
Step 5: Load the Dodecahedron
Load your soldered circuit and battery into the dodecahedron and mount your buttons and speaker, then solder each part to the board. Mount potentiometer, switch and headphone jack with hot glue. Don't forget to leave a means to enter the dodecahedron later to edit sketch/fix bugs/charge batteries! (I cut some joints so that one side would be able to slide off)
Step 6: Testing
Test your device by flipping the switch to the speaker option and adjusting the potentiometer. The pitch should go up as you press harder on the force-sensitive resistor. Each button corresponds to a different note.