88 Key Banana Piano

By: Liam

    • theme tags: bananas, instrument, piano, instruments
    • Language: English
    • for grade: 5 to University
    • duration: 2-4 Hours
    • need educator?: No

Make a full piano out of bananas using only one Makey Makey! And the wonders of combination.


Supplies

88 fruits/vegetables, strips of cardboard, insulated wires, exposed wires, tape and pen for labels.

Products:

steps

Step 1:

REMAP

First we'll need to remap the Makey Makey so it outputs 1-2-3-4-5-6-7-8-9-A-B-C-D-E-F-G-H-I

This will make it work with the 88 Key Piano program in Scratch.

Visit http://makeymakey.com/remap/ and follow the steps on screen to remap.


Step 2:

Once you've reached the remap stage, remap your Makey Makey as pictured.

It can be helpful to take your own screenshot or take notes on what-maps-to-what after remapping.

The keymap will save after you unplug your Makey Makey - don't worry about having to do this every time!


Step 3:

Wire up your Makey Makey!

Connect alligator clips to the front and the your small wires to the back. It can be helpful to add your own little labels to keep track of the outputs.


Step 4:

Set up your bananas!

And keep in mind you'll need lots of space. The one I've got setup here is 17 feet long (which is why it's doubled over).

Use card stock or cardboard to separated the black keys (carrots) from the white keys (bananas). If any of the fruits and veggies touch, two notes will sound when you touch each of them.


Step 5:

Now is a good time to take a look at the Scratch project to see how it works. Click SEE INSIDE to see the Scratch code.

Each note of the banana piano is actually pressing TWO keys on the Makey Makey. The Scratch program plays a sound when a combination of two keys is pressed, A-1 or B-7 for example.

Sidenote:

Using key combinations like this, you can create 153 unique keypresses on one Makey Makey!


Step 6:

Create hubs

You can use any number of things for this - I chose to use spoons.

Each key on the Makey Makey needs a hub because it'll be used multiple times and you can only connect so many alligator clips to one key-output.

In this example I used spoons, but next time I think I would use exposed wire for the hub with insulated wires tied to each hub for the notes.



Step 7:

Connect your keys!

This is easiest to do section by section first. If you remember from inside the Scratch project, the lowest 17 notes start with a When "1" key is pressed block.

Connect your first 17 keys to your "1" hub.

The next 16 keys to your "2" hub.

The next 15 keys to your "3" hub.

The next 14 keys to your "4" hub.

The next 13 keys to your "5" hub.

The next 12 keys to your "6" hub.

And the last key will connect to your "7" hub.

Be sure to keep everything labeled and organized - this part can get very tangled!


Step 8:

Now connect secondary cables to your bananas.

In section #1 the cables will go 2-3-4-5-6-7-8-9-A-B-C-D-E-F-G-H-I

In section #2 the cables will go 3-4-5-6-7-8-9-A-B-C-D-E-F-G-H-I

In section #3 the cables will go 4-5-6-7-8-9-A-B-C-D-E-F-G-H-I

In section #4 the cables will go 5-6-7-8-9-A-B-C-D-E-F-G-H-I

In section#5the cables will go 6-7-8-9-A-B-C-D-E-F-G-H-I

In section #6 the cables will go 7-8-9-A-B-C-D-E-F-G-H-I

In section #7 the only cable will be 8

Keep doing this until you've got your whole instrument hooked up so each banana has two cables coming out of it.

Sidenote:

It's best to think of this as a base 18 number system with each section being the 10s, the 20s, the 30s, etc. The reason each section gets shorter is that in this Scratch project we have to avoid instances of including both 1-2 and 2-1 because Scratch will read them as the same command, same for instances of 1-1 or 4-4 since Scratch we register that as only one key press.


Step 9:

Earth yourself

Now you need to make sure the player is connected to EARTH on the Makey Makey - you can do this using a conductive armband on the player's skin, a conductive floor pad if the player is barefoot, you can make a cool conductive aluminum foil hat for the musician to play, or however else you want to connect yourself to EARTH.


Step 10:

Scratch linkhttps://scratch.mit.edu/projects/131907755/


Play that piano!

And post pictures or videos of your 88 key Makey Makey piano!