ECE 110/120 Honors Lab Section : The Illini Piano

Introduction

Statement of Purpose

I wanted a project that would represent us. I wanted to create a musical instrument that is undeniably and unequivocally Illinoisan. In short, I'm making a piano keyboard using corn cobs. A corn piano. It will consist of two full octaves of fully-functioning corn keys to jam out with.

Background Research

Admittedly I am pretty new to the world of electronics, so I initially had no idea what I would do for my project. However, while I was brainstorming, I remembered a peculiar video I had seen where YouTubers Andrew Huang and Kick The Jet Engine built a musical instrument out of peaches, and proceeded to perform, what else, "Peaches" by The Presidents of the United States of America. I realized that as a musician, I would probably enjoy making something like this, but I wasn't really drawn toward it. This sat at the back of my mind for a few days while I was brainstorming other ideas. I didn't come back to that idea until a few days later, when I realized that it would be the perfect opportunity for a high-effort Illinois corn joke.

The idea is to make a two-octave piano keyboard layout, where corn cobs are the piano keys. These corn keys will be hooked up to an Arduino Mega, where they will all serve as capacitive sensors, and the signals from these corn key sensors will be sent to a laptop where they will be output via MIDI. This of course takes a lot of inspiration from the aforementioned peach instrument and will use the same capacitive sensing techniques that they use, although the sensor layout and code will be different. I wanted to go with this project because as a musician, it's always fun to create and work with musical instruments, and it just seems like a nice entry-level project to help ease me into the electrical engineering field.

Design Details

Block Diagram

System Overview

• Corn Keyboard - Two full octaves of sweet corny goodness. Each ear serves as a capacitive sensor that will send a signal to the Arduino.
• Breadboard - The central hub where all the ears of corn will connect to before their signal is sent off to the Arduino. Helps with organization and creates a sending/receiving loops with a measurable time difference when one touches an ear of corn.
• Power Supply Module - Connects to the breadboard and also supplies power to the Arduino.
• DC Power Adapter - Powers the power supply module.
• Arduino Mega 2560 - The brains. This will receive and process signals from the ears of corn, effectively turning them into capacitive sensors.
• Midi Shield - Hooked up directly on top of the Arduino. It gives the Arduino access to the MIDI communication protocol, allowing the signals from the capacitive corn sensors to be converted to MIDI signals. The MIDI shield sends these signals directly to a laptop.
• Laptop - Takes these signals and outputs them as piano/synth notes via MIDI software.

Parts

• Laptop - Already own
• Arduino Mega 2560 - Already own
• Breadboard Power Supply Module - Already own
• Breadboard - Already own
• Soldering Kit - $11.99
• Sparkfun MIDI Shield - $21.95
• MIDI Cable - $7.99
• DC Power Adapter - $9.99
• Some loooong jumper wires - like $10 maybe
• 1 MΩ Resistors - $5.95 for 100
• Plywood - $??
• 24 Ears of Sweet Corn - $12

Possible Challenges

• Cable management
• Learning how to code with Arduino completely cold
• The sweet corn cobs potentially not being conductive enough (although I tested them using an iOLab and some wires)
• Finding/making a non-conductive surface to put the corn on
• Potentially not having the right software to play MIDI

References

• Huang, A., 2014. "Peaches" - Played On Peaches.. [video] Available at: <https://youtu.be/C7NaFOBrhP8>.
• Kick The Jet Engine, 2014. How I Made An Instrument Out Of Peaches!. [video] Available at: <https://youtu.be/se212t100g8>.
• Z-HUT, 2018. How To Make A Capacitive Touch Sensor Switch Out Of Anything Metal Using An Arduino. [video] Available at: <https://youtu.be/lqg_Ze_OiiY>.