Player Py-ano

Have you ever seen pianos in movies or at an old-timey-themed restaurant that plays music and has the buttons move without a pianist? …(if not here is a video of one)... That type of Piano is the inspiration for this project. However, instead of a pneumatic or electromechanical mechanism modification to a real piano, I am just going to use CircuitPython, my adafruit circuit playground bluefruit chip, an adafruit neopixel light strip and a lasercut box designed like a piano. These will allow me to play a song on my makeshift “Player Py-ano” and light up the keys that would need to be pressed on a real piano.

-Access to a Laser Cutter (Available to me at the Boston College Hatchery)

-Two 19” x 19” wood or acrylic boards (Could be smaller if you are more adept at Adobe Illustrator)

-Adafruit Circuit Playground Bluefruit chip

-Adafruit NeoPixel LED Strip with Alligator Clips - I used 30 LEDs/Meter but would recommend 60 if this project should be replicated or a more flexible type of light string)

-Micro-USB to USB power cable

Optional:

-External USB Power Source

-Mini Bass Speaker, mohoss (You can use a similar external speaker) + Alligator Clips

My code is relatively straightforward and relies completely on concepts from the CircuitPython School youtube playlist. First I imported the necessary libraries (board, neopixel, time, digitalio and pwmio) and set up my hardware. This involved connecting my NeoPixel light strip to the Bluefruit, setting up my PWM speaker to generate notes and debouncing two buttons on my Bluefruit that will control playback.

Next, I set up my code. I created a dictionary of note frequencies that would map to values for different keys on the piano. Another dictionary maps the values of keys of the piano to specific LED lights on the strip. I created a play_note_with_light() function that simultaneously lights up the correct LED for the active note and plays the corresponding pitch of that note.

The main loop checks button states and plays the song accordingly.

A song can now be hard-coded into this file in two balanced lists. One list for notes and one list for the duration of those notes.

This project requires you to hard-code a song into the CircuitPython file. The type and complexity of song you play depends on how many holes you want to craft into the future laser-cut piano box. My box had 13 notes one whole octave C to B and a second partial octave higher than that C to A. There were no sharp or flat notes used because the spaces in between would not align with my light strip. My current version can also only play one note at a time.

Once you’ve picked your song, you just need to sequentially add each note that will be played into a list within CircuitPython. After this, track the amount of time each note is played and add a second note duration list with the amount of time, in seconds, of each note in the previous order.

You will need to find an image of a keyboard that will be appropriate for your project. I’ve provided an example. Then you will want to create the physical box dimensions using the MakerCase website. For this, consider your light source. My light strip had just over 1.3 inches between light strips and so I needed my box to accommodate about 17 inches to fit all 13 keys of the piano in width-wise. This is more important when you take both your keyboard image and your MakerCase dimensions into Adobe Illustrator to design your box. In here, you need to scale your box to the ruler tool in the Illustrator program. You should then add circles to be cut out and whatever other designs you want. Upload this design into your laser cutting program and follow laser cutter procedures.

Once I laser cut the box, you will need to glue it together. I reinforced the inner edges of my box with smaller pieces of scrap wood that I found would provide more glued-on surface area.

After gluing, you will want to tape on the light strip in the appropriate position. After this, you will want to find a comfortable position for your Bluefruit disk and external hardrive to sit while you operate this now-functioning Player Py-ano!

For anyone who may want to recreate this board, I have some suggested add-ons and improvements.

1. Use a string light and so you can build the dimensions of this piano more flexibly and incorporate the sharp notes (black keys).
2. Hardcode more than one song into the code by Bluetooth enabling your device (use structure from Professor Gallaugher’s GitHub code to set up a Bluetooth controlled remote and replace potentiometer features with songs).
3. Figure out how to play multiple notes at once. This will unlock much more complex songs.
4. Add a note value type that plays no frequency and so you can have pauses in the song.