E-TEXTILES AND WEARABLES¶

LIZA STARK E TEXTILES PRESENTATION NOTES:¶

ELECTRICITY : Is a path for electricity to flow How does it move? a stream of moving electrons create and electrical current Electrons want to move from power(positive) to ground (negative)

VOLTAGE (V): electrical pressure or force between two points. Measure in VOLTS

CURRENT (I): Rate at which electrical charge flows. Measure AMPS (amperes)

RESISTANCE (R): The amount of material that resists the flow of current. Measures OHMs

OHMS

Led’s Datasheet (datasheet is a document, printed or electronic that provides details about a product, like a computer, computer component, or software program. The datasheet includes information that can help in making a buying decision about a product by providing technical specifications about the product.) inform how volteos need the leed

ELECTRICAL CIRCUITS USEFUL SYMBOLS¶

ARDUINO¶

Arduino is an open-source electronics platform based on easy-to-use hardware and software. Arduino boards are able to read inputs - light on a sensor, a finger on a button, or a Twitter message - and turn it into an output - activating a motor, turning on an LED, publishing something online. You can tell your board what to do by sending a set of instructions to the microcontroller on the board. To do so you use the Arduino programming language (based on Wiring), and the Arduino Software (IDE), based on Processing.

"You don't need anyone's permission to make something great." Massimo Banzi helped invent the Arduino, a tiny.

You can download ARDUINO using this link

Arduino can not only send signals but can also receive them with two main purposes such as reading sensor data and receiving messages from other devices (shield, other Arduino, PC, etc.). The tickets will be classified into analog and digital .

ANALOG¶

The analog inputs of model One are those corresponding to pins A0 to A5. They are characterized by reading voltage values from 0 to 5 Volts with a resolution of 1024 (10 bits). If we divide 5 by 1024 we have to be able to detect variations in the level of the input signal of almost 5 mV. To do the reading of one of these pins we will write in our code

reading = analogRead (input pin);

"Reading" we replace it with the name of the variable where we want to store the value read and in "pin input" we will have to put the number of the analog pin we have chosen (0,1, ... 5) or the name of the variable that stores that number.

This function will return a value from 0 to 1023 in proportion to the level of the input signal. For a null input we will obtain the value 0, for an input of 2.5 Volts 511 (half of 1023) and for 5 Volts 1023.

DIGITAL¶

The digital inputs are the same as the digital outputs, that is, the pins ranging from 1 to 13. They differ from the analog ones because they are able to "understand" only two signal levels, LOW or values close to 0 V and HIGH or values close to 5 V. It may seem a disadvantage but in reality it may be the opposite. And not only because sometimes we only need to know two states (switch, button, presence sensor, limit switch ...) but because it is capable of reading digital pulse signals. This means that you can communicate.

For example, an analog temperature sensor such as the LM35 would increase the level of the voltage that reaches the board proportional to the temperature. However, a digital one like the ds18b20 what you would do is change the sequence of pulses and therefore the message that contains the temperature value.

Although the default digital pins are configured as inputs, if we want to do it manually we write in our code

pinMode (input pin, INPUT); To store the two possible LOW or HIGH values in a variable called “read” we write

reading = digitalRead (input pin);

FIRST APPROACH TO TEXTILE SAMPLES¶

Push botton switch¶

push button switch from lucrecia strano on Vimeo.

Shape memory¶

Shape memory from lucrecia strano on Vimeo.

FIST STEPS¶

I drew the design of my circuit on paper, identifying its components, this is my scanned drawing: On the one on the left I drew how to create the push botton switch dye that will make the circuit analogous. Then, it is a kind of sandwich where we first place a conductive textile, under the velostat (conductive sheet) and then the foam with a previous hole made in the center that will allow the contact of the two layers regulating the on / off of the LEDs. In the drawing on the right, black represents the ground, purple is a conductive thread that unites the red and blue LEDs forming a light blue and the green one that unifies all the green ones with conductive thread. The resistance is plotted on the ground and the switches on the conductive wires of the LED colors. The LEDs I have used are RGB 5mm, with a tweezer I made some circles with their legs to be able to sew them from there, just like in this picture: Once I had all the LEDs ready, I painted each leg a color (red, blue and green) to differentiate them and also the ground. Distribute them evenly by a strip of cloth and start sewing them with conductive thread. I joined all the ground first, then red and blue together and finally all the greens. It is very important that they do not touch each other, this would form a short circuit and not let the energy pass, that is, they would not turn on. I used 9V of energy, and a resistance of 33 Ω. I wanted to work recycling materials, so I looked at home for things that could help me. Use fruit and vegetable disposal networks to create a kind of textile sample. The LED strip covered it with an old cloth interlacing it with wires that I found unused at home.

ARDUINO CODE¶

int red_light_pin= 11;
int green_light_pin = 10;
int blue_light_pin = 9;
void setup() {
  pinMode(green_light_pin, OUTPUT);
  pinMode(blue_light_pin, OUTPUT);
}
void loop() {
  RGB_color(0, 255, 0); // Green
  delay(100);
  RGB_color(0, 0, 255); // Blue
  delay(100);
  RGB_color(255, 255, 125); // Raspberry
  delay(100);
  RGB_color(0, 255, 255); // Cyan
  delay(100);
  RGB_color(255, 0, 255); // Magenta
  delay(100);
  RGB_color(255, 255, 0); // Yellow
  delay(100);
  RGB_color(255, 255, 255); // White
  delay(100);
}
void RGB_color(int red_light_value, int green_light_value, int blue_light_value)
 {
  analogWrite(green_light_pin, green_light_value);
  analogWrite(blue_light_pin, blue_light_value);
 }