Concept
“Mube” is a combination of the word “music” and “cube”, which means a cube helps you to learn music. One of the biggest challenges for people who do not know the music is to recognize different music tones. Mube is a tangible user interface to help you remember six music tones in a playful way. To visualize music tones, I use six shaped notes to represent them. These notes came from a capella church’s method to help people to read music easier (Chase, 2009). I labeled each face of Mube with different music notes. If a user flips Mube, it will generate the corresponding tone of the music note that on the top face. Mube can also generate random tone. A user’s task is to flip Mube and find the right music note from the tone he/she heard. In this case, it is easier to learn to recognize different music tones.
Interaction
The input of Mube is an ADXL335 accelerometer which captures motion in 3-axis. By calculating the possible combinations of x, y, and z-axis, I can differentiate six orientations of a cube which represent six different music notes. The output is a Pizzo tone generator. It can generate different frequencies of sound under user-preset tempo. I use this Pizzo tone generator to make the sound of the music note that facing up for 1 second as well as a random sound (the one users need to find) for 2 seconds to differentiate them. Also, I use three LEDs with different colors to indicate the status and give user feedback with the result. A blue light means the system is operating and waiting for user to flip to another face. A red light means the user has not found the right music notes. A green light means the music notes facing up is the right tone generated by Mube randomly.
Technical Implementation
| A ADXL 335 accelerometer
| A Pizzo tone generator
| 3 LEDs (1red, 1blue, 1green)
| 2 resister (~100ohms)
| A Arduino Yun (I use Yun because I want to connect two Mube through Wifi)
| A 9V battery
| A ON/OFF switch
In order to put all of these electronics into a small cube, I placed every components on a mini breadboard carefully and them tied the breadboard to the Arduino so they won't fall apart when user flipping the cube.
I tried a number of different kinds of LEDs and pick the one with brightest lightness, which can shine through the container of Mube.
To save battery life, I embedded an ON/OFF switch between the battery and Arduino.
Challenge
One challenge I met is it is hard to adjust the accelerometer to perfectly horizontal or vertical. So I gave tolerance to all six possible orientations of a cube. I spent most of my time on testing the accelerometer and generate criteria for all six faces. I did another calibration after I put all the components into the container (the cube) by running the real functions.
Prototyping
For my first prototype, I use thick foam board to make a solid cube with right scale. The purpose is to try out the interaction of flipping a cube and how it can combine to music tones. Then I switched to using a thinner foam board to create a container for my electronics and using pins to assemble them together. I also considered using a 3D printer to make my final prototype with hollowed surface. However, I stopped this idea because of timing constraint and I am inexperienced with 3D modeling.
Challenge
I used foam blocks to fill in the empty spaces between Arduino and battery. Thus they will stay at the same place even no matter how I flipped the cube. I also cut some holes on the foam blocks so LED lights will not be blocked.
Result & Demo Video
