5. E-textiles¶

Reflection¶

I understood e-textile as a combination of fabric and electronics where cloth senses, reacts or communicates. In textile, normal wires are replaced by conductive yarns, fabrics and snaps with addition of microcontroller unit, LEDs and sensors that can easily bend and survive wear.

Terms that I will use for this week include:

i) Conductive material are materials that allows electricity to flow easily i.e conductive thread, velostat,copper fabric,snaps/magnets.

ii) Analog sensor- works in ranges perfect for pressure, stretch, bend while digital switch works in two state only either on/off; high/low. Digital switch is good for snaps, tilt balls.

iii) Ohm's Law- that states, electric current is proportional to voltage and inversely proportional to resistance.

V= I x R Where;

V= voltage (push)

I= Currrent (flow rate)

R= Resistance(opposition to flow) measuring how hard for electrons to move through a material.

Material property-Longer traces more R.

Contact resistance- where two pieces touch (snaps, fabric pads) you get extra R; pressure generally lowers it.

Velostat - R drops when pressed or stretched → perfect for analog sensing in e-textiles.

How to increase or decrease resistance (hands-on)

Increase R: longer, thinner, or higher-ρ path; add resistors in series.

Decrease R: shorten or widen the path; use lower-ρ material; add resistors in parallel.

In fabric: serpentine stitch = longer path (↑R). Double-track in parallel = wider path (↓R).

Inspiration¶

This weeks topic I am inspired by Leah Buechley who made LilyPad arduino, a tool that empowers people to build soft, flexible,fabric-based computers.

Kobakant

Kate Hartman

weekly assignment

To begin with my week's task I began with Arduino programming in TinkerCAD. I learned different parts of arduino UNO kit:

A. LED (Light Emitting Diode)- short is anode(+) while long is cathode (-)

B. Resistor

C. Button

D. Potentiometer

E. Motor

F. Digital Ports -- INPUT OR OUTPUT (Digital output + Fake Analog outout)

G. Analog Ports -- INPUT ONLY

H. RX= Receiver, TX = Transmit, L= Test blink (also connected to pin 13)

I. MCU Chip: The Brain – ATMEGA328P

J. USB Port

K. Reset button

L. Battery/ Power Port

M. Voltage Port (+)

N. GND - Ground Port (-)

O. Arduino on/off light

Tinkercad¶

Tinkercad is a free, web-based platform that allows you to design, simulate, and prototype electronics and 3D models.

I used the circuit for simulating my electronic circuit. Some of the components in the section include:

Arduino boards
LEDs
Resistors
Sensors
Motors
Breadboards

DigitalWrite¶

digitalWrite() is an Arduino function used to set a digital pin to either HIGH (on) or LOW (off).

It’s one of the most basic and essential functions for controlling components like LEDs, motors, or relays.

Parameters:¶

Pin → The digital pin number (e.g., 2, 13)

Value →:

HIGH (sets pin to 5V or 3.3V, depending on the board)

LOW (sets pin to 0V)

I did a few coding with the help of my instructor, Rico and I was able to come up with 6 blinking LED. At this point I understood the function of the + and - , the power pins and pinout.

AnalogRead¶

analogRead() is a function used in Arduino programming to measure the voltage at an analog input pin and convert it into a digital value that your program can use.

It reads the analog voltage (a continuous signal) from the specified analog pin like A0 and converts it to a digital number using the Arduino’s ADC (Analog-to-Digital Converter).

## Typical Uses

Reading sensor values like:

Light sensors (LDR)
Temperature sensors (LM35, TMP36)
Potentiometers (knobs)
Moisture or gas sensors

To test my skills, I used the potentiometer in my Tinkercad arduino simulation.

Arduino IDE¶

After programming my circuits in tinkercad, I tested it in arduino IDE. At first there was an error with my port;

I removed the USB cable, went to device manager (window key + x) then under ports (COM & LPT) to check the ports available. I connected back my USB cable and COM4 and COM3 were present. I chose COM3 and the same error appeared.

I replaced the USB Cable with another and the error was:

meaning my computer still can’t properly communicate with the Arduino board on COM7.

I unplugged my arduino once again, repeated the same procedure of device manager and ports (COM &LPT). My driver was missing. I downloaded CH340 driver and reuploaded my code back and it was functional.

I tried with neopixel ring. I used soldering iron to connect my jumper wired and connected it to the microcontroller.

Arduino + flex sensor + LED¶

Connecting the flex sensor to microcontroller and trying to bend/stretch a bit. When the the clothe bends, the lights goes off but then it stretches the lights is on.

Arduino + Hall Effect for digital soft sensor¶

Hall effect or magnetic sensor detects magnetic field prensense. I used this sensor to learn on how to do an interface with the microcotroller and collect and display data using the serial monitor.

Terms of core functions and variables¶

sensorPin is a variable that stores te pin number on the arduinoto where the sensor is connected. It makes the code easier to read and edit
sensorValue stores the data that you get from the sensor
Serial.begin() is a set-uo function that allows arduino to send and receive data through the USB cable to the serial monitor. A number is given called baud rate that shoud match the serial monitor baud rate.
Serial.println() sends data to the serial monitor and adds a new line so that tthe serial monitor prints each reading on a new line.

Swatches¶

I made a swatch using a conductive thread. I tested the conductive thread using the digital multimetre to know the current available after hand sewing.

I was pretty bad at hand sewing but managed to make a complete circuit, which failed me at the end.

Points to note for the failure; - no defined threading from +ve and -ve, the threads might have been in contact at one point. The sewing was also close to each other.

Did not draw a sketch to help me guide through sewing process.
I left more threads free.
Poor connection of thread to the items; paperclips, LED light and resistor.

After reviewed it and used another material to make a very simple sketch. And my circuit was working.

Tools¶

Arduino UNO
Arduino IDE
Tinkercad
Hall effect sensor
Flex sensor
Handbrake

How to compress video using handbrake¶

This week I had to learn how to compress my video using handbrake. Kohshi san helped me in seting up my handbrake to ensure the video is compressed while maintaining quality.