Concert Light Stick - Midterm Project


What's wotagei?

A Japanese concert culture.

Hatsune Miku, a virtual singer of a singing synthesizer application developed by Crypton Future Media.

"Wotagei or otagei (ヲタ芸 or オタ芸) refers to a type of dancing and cheering gestures performed by wota at concerts, fans of Japanese idol singers, involving jumping, clapping, arm-waving and chanting slogans." - wikipedia

Wotagei helps to make an active atmosphere at the concert, also enables the singer to feel being loved and supported by fans. It's an immersive experience that audience can take an active part in the concert and interact with the singer.


The current interactions between the singer and the audience.

There is a missing reaction from the singers and the stage to the audience, which makes me think about to do something in this part.

I began to generate ideas about how audience can interact with singers and the stage by brainstorming. Then I choice the idea that audience can control parts of the stage screen by their actions.

I analyzed the general actions of arm-waving that audience usually do at concerts, and also which kind of music rhythm is related to each action. This established the foundation for how I designed the sketches on the screen according to each action.

With Light Sticks

Without Light Sticks


Then I did some research about the sensors that I supposed to use in this project. My first blueprint is to design a wearable bracelet, which can detect the movement of the hands. So I did some investigation about wearable sensors and micro-controllers. The reason why I don't want to use Kinect or LeapMotion is obvious, that both of them are not possible for multiple users at a same time.

But unfortunately, I didn't have enough time to receive them by ordering online. So in this midterm project, I decided to make one demo by Arduino first.

The sensor I used was Accelerometer ADXL335.

It can give you analog readings for X, Y and Z axes.

Playing With ADXL335

I learnt how to link the sensor from the Internet and tried to get some analog output.

I tried to move the accelerometer in Y axes first like waving the light stick and got those numbers.

I drew a line graph based on these numbers of Y axes to help me recognize which number range is corresponding to which movement. (I entered the numbers manually in Excel, although I realized later that I can write a P5 code to draw this line graph.)

Then I tried to make 2 LEDs blink according to different movement of the accelerometer. I used the sensor to detect two different movements, one is moving my hand forward slowly, and the other is shaking my hands back and forth.

Although it looks easy in the blog, it was really hard to find the right number range of each movement. Since the sensor was not that stable, somehow the whole range of analog output would changed a little bit each time I run the program.

Make The Light Stick

Since I can't make a wearable thing with wearable sensors, I decided to make a light stick, on which I put the accelerometer.

But after I tested it, I realized that the range of analog output changed because I added a long stick between my hand and the sensor. So I had to analyze the number range again.

Link To P5

Since I can detect two different movements of hands now, it was time to make some P5 sketches.

The idea is that different sketches will appear on the screen according to different hand movements.

First I used Shiffman's code to generate some fireworks on the screen each time I shake my hand.

Then I wrote a sketch like echoes in P5. When I move hand slowly, it would generate more echoes. When I shake my hand, the echoes would disappear.

After that, I began to test it with some music. The BGM I used is Taylor Swift's Red, which is my favorite Taylor's song. After some tests, I realized that at the time when audience are shaking light sticks quickly, the rhythm of music is quick and the audience are very excited. So I have to make some exciting effect on the screen at this point instead of making the echoes sketch disappear.

After many tests, I decided to make the background color flash. ( Actually I was inspired by the words in RED, "Remembering him comes in flashbacks and echoes." so I draw flashbacks and echoes.)

What can be updated?

- Make it wearable!

- Detect more different movements and make more screen effects.

- Make the light stick flash or change colors according to different movements.

- Make it at lower cost materials. Think about multiple product and commercial viability.

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© 2019 Mengzhen Xiao