5. E-textiles

Research

A Fusion of Fabric and Technology

Introduction E-textiles, or electronic textiles, represent an innovative intersection of textile design and technology. These fabrics integrate electronic components to provide functionalities such as sensing, communication, and energy harvesting. With applications ranging from healthcare monitoring to smart clothing, e-textiles are reshaping the way we interact with our clothing and environment.

Definition of E-textiles are textiles that have been enhanced with electronic elements and functionalities. These can include conductive threads, sensors, and even energy sources like solar cells. The goal is to create fabrics that not only serve traditional purposes but also offer additional benefits, such as health monitoring, temperature regulation, and connectivity to other devices.

compositionThese textiles can incorporate various technologies, such as flexible circuits, LEDs, and even energy harvesting systems. The materials used often include:

• Conductive fibers: These allow for the transmission of electrical signals, enabling communication between components.
  

• Sensors: Integrated into the fabric, sensors can monitor health parameters, environmental conditions, or user interactions.
  

• Actuators: These components can perform actions based on data received from sensors, such as adjusting temperature or activating alerts.
  

Applications of E-Textiles

1. Healthcare: E-textiles are transforming healthcare by enabling continuous health monitoring. Smart garments equipped with sensors can track vital signs like heart rate, respiration, and temperature, providing valuable data to healthcare professionals and patients. This technology enhances preventive care and can lead to timely interventions.

2. Sports and Fitness: Athletes are leveraging e-textiles for performance optimization. Smart sportswear can monitor body metrics in real-time, helping athletes refine their training regimens and prevent injuries. For example, shirts with integrated sensors can measure muscle strain and hydration levels during physical activities.

3. Fashion: Designers are increasingly incorporating e-textiles into fashion, creating garments that can change color or pattern in response to environmental cues. This innovation not only enhances aesthetic appeal but also allows for personalized fashion experiences.

4. Smart Home Integration: E-textiles are finding their way into smart homes. Curtains, upholstery, and even carpets can be embedded with sensors that respond to light, temperature, or occupancy, improving energy efficiency and user comfort.

Development:

Research in e-textiles focuses on improving the integration of technology with textiles while addressing challenges like durability, washability, and comfort. Key areas of investigation include:

• Material Innovation: Developing new conductive materials that are flexible, lightweight, and compatible with standard textile manufacturing processes.
• Energy Harvesting: Creating textiles that can harvest energy from motion, light, or heat to power their electronic components, enhancing sustainability.
• User Interaction: Exploring ways to make e-textiles intuitive and user-friendly, ensuring seamless interaction with technology.

Environmental Considerations

As the e-textile industry grows, so does the need for sustainable practices. Researchers are investigating eco-friendly materials and processes that minimize environmental impact, such as using organic dyes and reducing water consumption during manufacturing.

Challenges and Future Directions

Despite the promising advancements, the e-textile industry faces several challenges, including:

• Durability: Ensuring that electronic components can withstand regular wear and tear, as well as washing cycles.
• Cost: High production costs can limit accessibility and widespread adoption of e-textiles.
• User Acceptance: Educating consumers about the benefits of e-textiles and addressing privacy concerns related to data collection.

The future of e-textiles is promising, with ongoing innovations likely to lead to more versatile and user-friendly applications. As research continues, we can expect to see e-textiles that are not only functional but also fashionable and sustainable.

E-textiles represent a significant evolution in textile technology, combining functionality and aesthetics in innovative ways. With applications across various industries, from healthcare to fashion, the potential for e-textiles to transform our interaction with fabrics is immense. As research and development continue to advance, we are on the brink of a new era in textile innovation.

References & Inspiration

Below are some key references and inspirations:

1. Research Studies:

"Smart Textiles: Technologies and Applications" (2016) by Vladan Koncar explores the integration of sensors and actuators in fabrics.

"E-Textiles in Wearable Computing" (2020) highlights innovations in conductive fibers and flexible circuits.

"Innovations in E-Textiles" (2022) by Maria Arboleda focuses on conductive materials like graphene for textile-based electronics.

2. Industry Inspirations:

Google Jacquard integrates touch-sensitive tech into everyday fashion, like Levi's jackets.

Cutecircuit creates LED-embedded and haptic garments, merging fashion with interactivity.

OMsignal develops e-textiles for health monitoring, including garments that track vital signs.

3. Designers and Projects:

Pauline van Dongen incorporates solar cells into clothing for energy-harvesting designs.

Studio XO creates interactive tech-embedded outfits for artists like Lady Gaga and Björk.

E-Textile Circuit

In e-textiles, the choice between series and parallel circuits can greatly impact the functionality, brightness, and battery life of your project. Here’s a breakdown of both types, and why you might choose one over the other in an e-textile design:

Series Circuits

In a series circuit, components are connected one after another in a single path for the current to flow. Here are some key points:

• Current: The same current flows through each component.
• Voltage: The total voltage is divided across the components. This can be problematic for LEDs since each LED will receive only a fraction of the total voltage, potentially dimming them.
• Failure: If one component fails or a connection breaks, the entire circuit stops working.

When to Use Series in E-Textiles:

• Rarely used for LEDs in e-textiles, as they typically require more voltage per LED.
• Suitable for low-power applications where multiple components can share the same current, such as in small resistors or sensors that don’t need individual power control.

The formulas for series and parallel circuits are essential for understanding how voltage, current, and resistance behave in each configuration.

Series Circuit Formulas

1. Current (I): The current through each component in a series circuit is the same:
   I_total = I₁ = I₂ = I₃ = ...

2. Voltage (V): The total voltage is the sum of the voltages across each component:
   V_total = V₁ + V₂ + V₃ + ...

3. Resistance (R): The total voltage is the sum of the voltages across each component:
   R_total = R₁ + R₂ + R₃ + ...

Example Series Circuit Layout:

 (Battery Pack) — (LED 1) — (LED 2) — (LED 3) — (Resistor) — (Microcontroller)

Parallel Circuits

In a parallel circuit, each component has its own path to the power source, meaning they are all connected independently.

• Current: The total current is divided among the components, so each branch can draw its own amount.
• Voltage: Each component receives the full voltage of the power source, making LEDs brighter and more reliable in parallel circuits.
• Failure: If one component fails, the others continue to work since they each have a separate connection to the power source.

When to Use Parallel in E-Textiles:

• Preferred for LEDs, as each LED will receive full power and maintain brightness.
• Ideal for designs that need independent control over each LED or component, such as individual response to touch or sound.

Parallel Circuit Formulas

1. Current (I): The total current is the sum of the currents through each parallel branch:
   I_total = I₁ + I₂ + I₃ + ...

2. Voltage (V): The voltage across each branch is the same as the total voltage:
   V_total = V₁ = V₂ = V₃ = ...

3. Resistance (R): The total resistance in a parallel circuit is calculated as follows:
   1/R_total = 1/R₁ + 1/R₂ + 1/R₃ + ...

Example Parallel Circuit Layout:

  (Battery Pack)
 |       |       |
 (LED 1) (LED 2) (LED 3)

Process and workflow

Exploring LED Circuits: From Simple Connections to Fabric-Integrated E-Textiles

Our journey into e-textiles began by mastering the basics of an LED circuit before introducing it into any fabric. This foundational step was essential for ensuring that we understood how to establish proper connections and successfully light up the LED. Using simple alligator clips and LEDs, we tested the circuit's functionality, confirming that everything worked as expected. This phase gave us confidence in our setup and the knowledge to move forward.

Once we confirmed the LED was lighting up correctly, we progressed to the exciting part—integrating conductive materials like conductive thread and tape into fabric. These materials allowed us to sew the circuit directly onto textiles, blending technology with the art of fabric design. By threading conductive thread into the fabric and connecting components with conductive tape, we created a seamless bridge between electronics and textile art, demonstrating how e-textiles can offer interactive, responsive designs.

We also experimented with conductive fabric to explore its ability to carry electricity. This setup added an interactive element, enabling users to touch or manipulate the fabric to complete the circuit, triggering the LED to light up. The tactile experience highlighted the potential of combining technology with textiles in unique and innovative ways.

In another experiment, we connected two LEDs to a single battery to see if they could light up simultaneously. We tested various LED colors and noticed differences in brightness and power consumption, revealing that different LED colors can have varying energy requirements. This experimentation provided valuable insights into how color choice and power distribution could affect e-textile designs.

By integrating these materials and techniques, we demonstrated the endless possibilities for creating interactive, technology-driven textiles that can respond to user interaction in real-time.

Integrating Arduino with Sound Sensors: A Hands-On Exploration

As I began my journey into learning Arduino, one of the key experiments involved connecting an Arduino Uno board to a sound sensor module. The process started with a bit of trial and error, especially when it came to matching the correct jumper wires with the digital and analog pins on the board. Despite the initial challenges, this hands-on experience helped me grasp the fundamentals of how to interface sensors with the Arduino platform.

The sound sensor module itself includes a microphone and a potentiometer, which we adjusted to fine-tune its sensitivity. This allowed us to understand how environmental input, such as sound, could trigger a response from the Arduino. In this experiment, the sensor captured sound waves and converted them into electrical signals. The module's three key pins—signal (S), ground (GND), and voltage (VCC)—were connected to the appropriate pins on the Arduino board.

We then programmed the Arduino to respond to specific sound levels. For example, when the sound sensor detected noise above a set threshold, it triggered the rotation of a motor by 90 degrees. This setup demonstrated how real-world inputs could be transformed into mechanical actions, marking a pivotal step in our understanding of sensor-based interactions and their applications in e-textiles and beyond.

Code Example

I began my work with the stretch sensor because the module I had used a few weeks ago seemed ideal due to its flexibility. Initially, everything worked smoothly when I used its UNO board. However, when I switched to the Flora board, the sensor stopped functioning properly. Despite trying various approaches, neither of the two code samples I had worked successfully with Flora. After many failed attempts, I couldn't help but recall Edison's quote: "I have not failed. I've just found 10,000 ways that won't work."

Here are some sample code for Flora and stretch sensor,they are not worked well:

Sample-1

// the setup routine runs once when you press reset:
void setup() {
  // initialize serial communication at 9600 bits per second:
  Serial.begin(9600);
}

// the loop routine runs over and over again forever:
  void loop() {
  // read the input on analog pin A0:
  int sensorValue = analogRead(6);  // Use A0 instead of A6 for Nano 33 BLE
  // print out the value you read:
  Serial.println(sensorValue);
  delay(400);  // delay in between reads for stability
}

Sample-2

// Analog input pin where the sensor is connected
const int sensorPin = A6;

// Variable to store the PWM value (0-255)
int pwmValue = 0;

void setup() {
  // Set pin 9 as an output
  // pinMode(pwmPin, OUTPUT);
  pinMode(sensorPin, INPUT);

  // Initialize serial communication at 9600 bps
  Serial.begin(9600);
}

void loop() {
  // Read the analog input value from the sensor (0-1023)
  int sensorValue = analogRead(sensorPin);

// Map the sensor value (0-1023) to a PWM value (0-255)
pwmValue = map(sensorValue, 0, 1023, 0, 255);


Serial.print("Sensor Value: ");
Serial.println(sensorValue);

// Wait a bit before the next loop
delay(100);
}

I didn’t just modify the codes; I also experimented with different stitching techniques. In the first model, I used a twisted stitching pattern around the design, while in the next, I opted for a straight, simple line. Interestingly, despite these adjustments, there was no noticeable difference in the final outcome.

In the meantime, I began preparing for the next project by using a vinyl cutter to cut the copper sheet. Although my first attempt was unsuccessful, my subsequent cut was much better, and I used it for the next necklace.

Analog Sensor

Before diving deeper into coding, I began constructing an analog sensor using three LEDs to create a parallel circuit. With the aid of a 3-volt battery and a small Velostat, I was able to turn on the LEDs by pressing on the Velostat. The addition of acetate to the setup yielded a delightful and visually appealing result, especially after my earlier setbacks.

Results

Refusing to give up, I shifted my focus to using the Flora board for lighting on this module. This time, I succeeded, managing to implement and advance models like simultaneous blinking and staggering the blinking of LEDs. It was a rewarding breakthrough after the initial setbacks.

BlinkingStagger BlinkingBlinkig with Music

// Define the pin for the LEDs
 int ledPin = 6;  // Choose an available output pin on Flora
  void setup() {
 // Set the pin as OUTPUT
 pinMode(ledPin, OUTPUT);
}

void loop() {
 // Turn the LEDs on
 digitalWrite(ledPin, HIGH);
 delay(1000);  // Wait for 1 second

// Turn the LEDs off
digitalWrite(ledPin, LOW);
delay(1000);  // Wait for 1 second
}

 int led1 = 6;  // LED 1 on PWM pin D6
 int led2 = 10; // LED 2 on pin D10
 int led3 = 9;  // LED 3 on pin D9

 void setup() {
 pinMode(led1, OUTPUT);
 pinMode(led2, OUTPUT);
 pinMode(led3, OUTPUT);
}

void loop() {
 // Fade in LED 1 while keeping others off
 for (int brightness = 0; brightness <= 255; brightness += 5) {
 analogWrite(led1, brightness);  // Fade LED 1
 digitalWrite(led2, LOW);
 digitalWrite(led3, LOW);
 delay(30);
}

// Fade out LED 1 and blink LED 2
 for (int brightness = 255; brightness >= 0; brightness -= 5) {
 analogWrite(led1, brightness);  // Fade LED 1
 digitalWrite(led2, HIGH);       // Turn on LED 2
 digitalWrite(led3, LOW);
 delay(30);
}

 // Blink LED 3
 digitalWrite(led2, LOW);
 digitalWrite(led3, HIGH);
 delay(500);
 digitalWrite(led3, LOW);
 delay(500);
}

 int led1 = 6;  // First LED connected to D6
 int led2 = 10; // Second LED connected to D10

 void setup() {
 pinMode(led1, OUTPUT);  // Set pin D6 as output
 pinMode(led2, OUTPUT);  // Set pin D10 as output
}

void loop() {
 // Rhythmic ticking pattern (short and sharp blinks)
 for (int i = 0; i < 3; i++) {
 digitalWrite(led1, HIGH);
 delay(250); // ON for 250ms
 digitalWrite(led1, LOW);
 digitalWrite(led2, HIGH);
 delay(250); // Switch to LED2 for 250ms
 digitalWrite(led2, LOW);
}

// Dramatic pause
 delay(1500); // Wait for 1.5 seconds

 // Slower, dramatic flashes, building tension
 digitalWrite(led1, HIGH);
 delay(1000); // LED1 ON for 1 second
 digitalWrite(led1, LOW);
 digitalWrite(led2, HIGH);
 delay(1000); // LED2 ON for 1 second
  digitalWrite(led2, LOW);

// Longer flashes, simulating the crescendo
 digitalWrite(led1, HIGH);
 delay(1500); // LED1 ON for 1.5 seconds
 digitalWrite(led1, LOW);
 delay(500);  // Pause for 500ms
 digitalWrite(led2, HIGH);
 delay(1500); // LED2 ON for 1.5 seconds
 digitalWrite(led2, LOW);

 // Repeat the pattern
}

After successfully launching this captivating game adorned with vibrant lights, I began to envision how these lights could be synchronized to music. Inspired by the soundtrack of Interstellar, I used artificial intelligence to create a code that choreographs the lights to dance along with the music. This sparked the beginning of an exciting new journey in my creative exploration.