Hey everyone! We just got a shipment in from Adafruit, a New
York based Electronics Company, with tons of really cool items. This includes a
Raspberry Pi board with the camera module, an LED 8x8 matrix, a Arduino shield that logs temperature, and a
Makey Makey. We started experimenting last week with a few of these items and we had a lot of fun using the Makey Makey.
The Makey Makey is a device that allows for any conductive material to become a touch sensor. For example we could make a banana into a touch sensor so that when we touched the banana it makes a sound. So far we have made pizza dishes, pencil drawings, skin, desk trays and keys into touch sensors. Based on when you touch any of these items, a sound will play. This is because the Makey Makey is seeing that you touched something and then registering this into the computer as a keystroke. We ran an application that showed that the keystrokes entered would make various sounds.
The Makey Makey is actually a pretty simple device to use and setup. First, hook it up to a computer and download all the necessary drivers, which allows the Makey Makey to act as a keyboard. Then, connect an alligator clip to the various arrow or keyboard keys. For example, there is an up arrow key which you would hook an alligator clip up to and then you would hook the other end up to a conductive material (ex. a pizza dish). Afterwards, hook another alligator clip up to a ground pin on the Makey Makey and hold that in your hand. When you go to touch the conductive material, it will register this as a key press.
The Makey Makey is an ATMega32u4 chip running firmware from the Arduino Lenardo board. The board can be reprogrammed to work with any mouse or arrow keys if desired. Electrically, the principal behind how the Makey Makey detects touch is by grounding an input. Basically, when you touch what ever is connected to the Makey Makey, and if you are connected to the ground, you are effectively grounding the circuit to a logic 0. In order to keep the circuit to a logic 1, before the object is touched, a 22 mega ohm pull-up resistor is used. This is basically a resistor connected to a positive voltage. Overall, the Makey Makey is just seeing when it detects a logic 0. In order to remove any electrical noise in the circuit a running average is used to help differentiate signal from noise.
It's been a lot of fun using the Makey Makey over the past week and we look forward to making more musical projects. What do you think about possibly combining the Kinect and the Makey Makey?!
Below is a video of what we've made our Makey Makey do:
~Anthony