5. E-textiles¶

Research¶

This week we started working on e-textiles ! a very fascinating opening into this field of textile and electronics, I'm very passionate about the possibilities for weaving these techologies. This introductory week, i focus on learning how to make circuits and translate them into soft conductive materials.

Notes¶

Some important notes for this lesson would be: · Vocabulary list by Liza Stark

· Ohm law , V=IxR

V, Voltage. I, Current. R, Resistance

Whis this formula, we can canculate the correct amount of charge given the resistance we have, or we can calculate the Resistance we need given the Voltage of our power source and how much we need for our output device.

· We can work with Digital or Analog instructions for our circuits. Digital works with Binary code (0111001), while Analog can range on infinitude of possibilites between the minimum or maximum of our output. For example, Digital would be when we have an ON/OFF command for our output, and Analog would be when we have a presure sensor that makes our output variate depending on the intensity of the input, being multiple the posibilities, (fading).

· We can work with "hard to soft" connexions, and this can be permanent (by souldering) or detachable connexions (with any kind of removable connexion, for example a metallic press button).

· !! On a LED light, the longer leg is the anode (positive), while the shorter one is the cathode (negative).

· I've learnt the differences between a series or a paralel circuit.

· We started working with a microcontroller, for example: Arduino, to send digital or analog instructions to our e-textiles and circuits. The microcontroler is the in-between the input and output. In Arduino we have Power pins, 5 or 3,3V, GND pins = ground (-), and Digital or Analong pins. Analog are only the PWM or ~.

References & Inspiration¶

HYBRID BODY LAB _ WOVEN BOT

Robotic Barrier Construction through Weaved, Inflatable Tubes In this project, HYBRID BODY LAB investigate the use of extruded tubes weaved around existing environmental features to quickly assemble light-duty barriers, e.g. against wind or snow. By extruded tubes, they are referring to the recent advancement in ‘vine-robots’ where everted, flexible polymer tubes can be inflated several meters out from their deployment mechanism.

Tools ⚙¶

Process and workflow¶

I started working on creating a soft circuit with a soft press button for a LED light. To then start working with Arduino, to get familiarize with the program I worked with some simple on/off digital and analog codes.

Code Examples¶

Digital instructions¶

First i played around the blinking light

//*blink light_01
 * I turn on a led and I turn it off
 */

int led_pin = 7; //define the pin where the Led is connected

void setup() {

  pinMode(7, HIGH); //define pin of the Led as an output

}

void loop() {

  digitalWrite(7, HIGH); //turn the Led on   
  delay(600);                 //wait 600millisecond 
  digitalWrite(7, LOW);  //turn the Led off 
  delay(600);                 //wait 600millisecond

}

You can introduce the sequence of on/off as you like and it will repeat itself on loop:

//*blink light_02
 * I turn on a led and I turn it off at different speeds
 */

int led_pin = 7; //define the pin where the Led is connected

void setup() {

  pinMode(7, HIGH); //define pin of the Led as an output

}
void loop() {

  digitalWrite(7, HIGH); //turn the Led on   
  delay(600);                 //wait 600millisecond 
  digitalWrite(7, LOW);  //turn the Led off 
  delay(600);                 //wait 600millisecond
  digitalWrite(7, HIGH); //turn the Led on   
  delay(200);                 //wait 600millisecond 
  digitalWrite(7, LOW);  //turn the Led off 
  delay(200);                 //wait 600millisecond
  digitalWrite(7, HIGH); //turn the Led on   
  delay(200);                 //wait 600millisecond 
  digitalWrite(7, LOW);  //turn the Led off 
  delay(200);                 //wait 600millisecond
  digitalWrite(7, HIGH); //turn the Led on   
  delay(1000);                 //wait 600millisecond 
  digitalWrite(7, LOW);  //turn the Led off 
  delay(1000);                 //wait 600millisecond
  digitalWrite(7, HIGH); //turn the Led on   
  delay(1000);                 //wait 600millisecond 
  digitalWrite(7, LOW);  //turn the Led off 
  delay(1000);                 //wait 600millisecond
  digitalWrite(7, HIGH); //turn the Led on   
  delay(1000);                 //wait 600millisecond 
  digitalWrite(7, LOW);  //turn the Led off 
  delay(1000);                 //wait 600millisecond
  digitalWrite(7, HIGH); //turn the Led on   
  delay(1000);                 //wait 600millisecond 
  digitalWrite(7, LOW);  //turn the Led off 
  delay(1000);                 //wait 600millisecond
  digitalWrite(7, HIGH); //turn the Led on   
  delay(200);                 //wait 600millisecond 
  digitalWrite(7, LOW);  //turn the Led off 
  delay(200);                 //wait 600millisecond
  digitalWrite(7, HIGH); //turn the Led on   
  delay(200);                 //wait 600millisecond 
  digitalWrite(7, LOW);  //turn the Led off 
  delay(200);                 //wait 600millisecond
}

Then i learnt how to introduce a button to turn off the ligh:

/*  Automatización para Todos
 *  www.automatizacionparatodos.com
 *  
 *  Como utilizar un botón con arduino
 *  
 *  EJEMPLO 01
 *  
 *  Ejemplo para encender y apagar un LED con un botón.
 *  
 */

// Crear variables para el manejo de los pines
int pinLED = 9;
int pinBoton = 2;

// Crear variable para estado del botón
bool boton = LOW;

void setup() {
  // Configuración de los pines de entrada y salida
  pinMode(pinLED,OUTPUT); // Salida digital para el LED
  pinMode(pinBoton,INPUT); // Entrada digital para el botón
}

void loop() {
  // Leer el estado del botón y encender o apagar el LED
  boton = digitalRead(pinBoton);

  if(boton == HIGH){            // Si el botón está pulsado
    digitalWrite(pinLED,HIGH);  // Enciende el LED
  }
  else{                         // Si no
    digitalWrite(pinLED,LOW);   // Apaga el LED
  }
}

Analog instructions¶

Then moving into Analog intructions, fading the light would be an easy example to experiment with,, important to remember to change the pin led to a PWM one:

/*
  Fade - part of the Examples of Arduino IDE

  This example shows how to fade an LED on pin 11 using the analogWrite()
  function.

  The analogWrite() function uses PWM, so if you want to change the pin you're
  using, be sure to use another PWM capable pin. On most Arduino, the PWM pins
  are identified with a "~" sign, like ~3, ~5, ~6, ~9, ~10 and ~11.

  This example code is in the public domain.

  http://www.arduino.cc/en/Tutorial/Fade
*/

int led = 9;           // the PWM pin the LED is attached to
int brightness = 255;    // how bright the LED is
int fadeAmount = 150;    // how many points to fade the LED by

// the setup routine runs once when you press reset:
void setup() {
  // declare pin 9 to be an output:
  pinMode(9, 255);
}

// the loop routine runs over and over again forever:
void loop() {
  // set the brightness of pin 9:
  analogWrite(9, 255);

  // change the brightness for next time through the loop:
  brightness = brightness + fadeAmount;

  // reverse the direction of the fading at the ends of the fade:
  if (brightness <= 0 || brightness >= 255) {
    fadeAmount = -fadeAmount;
  }
  // wait for 30 milliseconds to see the dimming effect
  delay(1000);

  // fade:
  analogWrite(9, 150);

  // wait for 30 milliseconds to see the dimming effect
  delay(1000);

}

Result¶

I decided to make a pillow with a compostable material i made during the week of BioFabricating Materials, this material is made of pectin, glycerin and dried mate herb after being infused. This pillow has an analog press on button that makes a line of LED lights light up on a degradable scale of intensity. This was made with a paralel circuit, conductive thread, some LED lights and a power source. Afterwards, i stuffed the pillow with some cleaned raw wool we have at the biolab.

Firstly, i laser cut the pieces for the pillow, on the pectine-based material and on the coductive fabric:

Material: Bioplastic_pectin + mate herb
Thickness: 0,3 mm

CUT
Speed: 50
Min. power: 50
Max. power: 56

Then i put together the paralel circuit in one of the sides of the pillow with LED lights and conductive thread, then i stitch together both pannels and the button.