Introduction: Tetrahedron LED Light

Picture of Tetrahedron LED Light

I am always interested in the idea of "module". It provides freedom to create a unique piece of each user.

This intractable will teach you how to make a pressure sensitive module tetrahedron light.

The materials you need is as blow.



single color LEDs

Attiny 45 or Attiny 85

Arduino board

Piezo element

Copper tape

3V cell battery

Battery holder

Other materials:

Foldable translucent plastics

Masking tape


Hot glue gun

Step 1: Fold the Tetrahedron

Picture of Fold the Tetrahedron

Cut the plastics into the shape as the picture. The width of the triangle is 3.5 inch. You can adjust the size, but make sure it's not too small to fit all the circuit in.The plastics may be a little bit hard to work with. Make sure you use a folding bone to score it before you start folding.

Step 2: Build the Circuit

Picture of Build the Circuit

Now let's start to make the circuit.

If you are not familiar with working with a Attiny, please see this link.

It will teach you how to use your arduino board to program the attiny.

The code that need to upload to Attiny is as below:

// these constants won't change:
const int ledPin = 0; // led connected to digital pin 0 const int knockSensor = 3; // the piezo is connected to analog pin 3 const int threshold = 60; // threshold value to decide when the detected sound is a knock or not

// these variables will change: int sensorReading = 0; // variable to store the value read from the sensor pin int ledState = LOW; // variable used to store the last LED status, to toggle the light

void setup() { pinMode(ledPin, OUTPUT); // declare the ledPin as as OUTPUT // Serial.begin(9600); // use the serial port }

void loop() { // read the sensor and store it in the variable sensorReading: int sensorReading = analogRead(knockSensor); // if the sensor reading is greater than the threshold: if (sensorReading >threshold) { // toggle the status of the ledPin: ledState = !ledState; // update the LED pin itself: digitalWrite(ledPin,ledState); // send the string "Knock!" back to the computer, followed by newline // Serial.println("Knock!"); } delay(100); // delay to avoid overloading the serial port buffer }

Step 3: Assemble the Tetrahedron

Put the circuit inside the tetrahedron. Make sure the circuit is working before you put it in.

Tape the piezo and the magnetics together on one of the side of the tetrahedron. And put three other magnetics on the other three sides as well. Watch the positive and negative side of the magnetic and make sure they attract when two tetrahedrons are put together.

Step 4: Finish and Play!

Picture of Finish and Play!

Make as many pieces as you want! Now you can start to play with your module lights and assemble them in different ways as creatively as possible.