UDOO Theremin

This project is a really easy and straightforwarding excercise for music lovers, makers and sensors fanatics. What we did is simply emulate a Theremin, a really iconic musical instrument, with PureData, UDOO and an Arduino Sketch. To detect the movement of the hand, which is going to affect the sound modulation of our Theremin, we used a IR Ping sensor.

So, let’s start!

First we connect the IR sensor to Udoo.

Then, we create, compile and  upload the Arduino Sketch:

int IRpin = A0;
int distance = 0;
int msg = 0;

void setup() {
  // put your setup code here, to run once:
  Serial.begin(115200);
}

void loop() {
  // put your main code here, to run repeatedly: 
  distance = analogRead(IRpin);
  
  if (distance < 100) {
    distance = 100;  
  } else if (distance > 900){
    distance = 900;
  }

  msg = map(distance, 100, 900, 0, 255);
  Serial.write(msg);
}

What this does is basically send as analog serial measurements, the distance from it from our hands, and sends the data via serial port. It works within a range from 0 to 255, and ideally it works best detecting our hands in a distance ranging from 4 to 30 centimeters.

We then set up PureData, which is going to hook to serial /dev/ttymxc3 via comport, an external which enables PureData to handle serial port communications. And set up appropriately. This was our result, fell free to experiment with it and add more channels!

When everything is set up, just launch PureData’s DSP, and enjoy your brand new digital Theremin!

You can download the Arduino Sketch and the PureData project below: