12. Skin Electronics

Research

Inspiration & Concept

This week, I found my inspiration in creating a party mask that light up on the skin. To start, I focused on researching the right design and figuring out the best way to make connections—whether with wires, conductive ink, or copper tape. I also explored which sensor would work best with the body, such as a temperature sensor, heartbeat sensor, or light sensor. Additionally, I considered the type of lighting I’d use, like LED lights, neopixels, or even glowing powders. As I worked through these ideas, everything started to come together once I finalized the design!

CREDITS

1

2

3

Conductive Ink

Explore the use of conductive ink on the skin.

Materials Used:

Carbon powder

Glue

Vinegar

Water

Process:

Mixed carbon powder with varying proportions of glue, vinegar, and water to create different conductive ink formulations.

Applied the mixtures to test surfaces and measured their electrical resistance.

Goal: Identify the optimal formula for conductive ink that adheres well to the skin and provides effective conductivity.

Circut design

Connections

Component	Connection	Pin/Voltage
Thermistor	One leg connected to	Pin 2
	Other leg connected to	3.3V (positive rail)
	10k ohm resistor connected between	Pin 2 and GND
LED	Positive (anode) leg connected to	Pin 21 (PWM-capable)
	Negative (cathode) leg connected to	GND

tip

Coding

#define TEMP_PIN 2       // Analog pin for the thermistor
#define LED_PIN 7        // PWM pin for the LED (must support analogWrite)

void setup() {
  Serial.begin(115200);   // Start serial communication for debugging
  pinMode(LED_PIN, OUTPUT); // Set the LED pin as an output
}

void loop() {
  // Read the sensor value from the thermistor
  int sensorValue = analogRead(TEMP_PIN);

  // Convert the sensor value to temperature in Celsius (using a basic formula for thermistor)
  float voltage = sensorValue * (3.3 / 4095.0);  // Convert sensor value to voltage (assuming 3.3V reference)

  // Use a simplified approximation (this will depend on your thermistor's characteristics)
  float temperature = (voltage - 0.5) * 26.3; // Convert voltage to temperature for a typical thermistor

  // Print the temperature to the Serial Monitor
  Serial.print("Temperature: ");
  Serial.print(temperature);
  Serial.println(" C");

  // Control the LED fade effect based on the temperature
  if (temperature >= 30) {  // If temperature is 30°C or above, fade in the LED
    fadeLED(); 
  } else {
    analogWrite(LED_PIN, 0); // If temperature is below 30°C, turn the LED off
  }

  delay(1000);  // Delay 1 second before reading again
}

// Function to fade the LED in, stay on for 1 second, and fade out
void fadeLED() {
  // Fade in
  for (int brightness = 0; brightness <= 255; brightness++) {
    analogWrite(LED_PIN, brightness);
    delay(10);  // Adjust this delay to control the fade speed
  }

  // Stay fully lit for 1 second
  delay(1000);

  // Fade out
  for (int brightness = 255; brightness >= 0; brightness--) {
    analogWrite(LED_PIN, brightness);
    delay(10);  // Adjust this delay to control the fade speed
  }
}

3D printing

This Crystal was made in Textile Scaffold week and I took the advantage of this idea to make 3d print pieces !!

Fabrication files

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1. File: Crystal ↩

2. File: Crystal2 ↩