8| Wearables

Inspirations

Basic Ouput (LEDs) - Arduino

How to drive an output device (a load) with Arduino

I followed Emma's tutorials, and made a summary table of all the different implementations I tried with the Arduino.

Implementation	SKETCH	RESULT
BLINK
Only one Led / Only one load: Blink a Led, turn on/off a load, Using the Arduino Sketch "Blink" 01_blink_led		via GIPHY
INTENSITY
Set the intensity of the Led, control the amount of current 02_led_analogwrite		via GIPHY
READ SENSOR
Led and Switch / Load and a Digital Sensor , Read the Sensor - 03_read_DigitalSensor
DIGITAL SENSOR - BUTTON ON/OFF
Led and Switch / Load and a Digital Sensor : if the switch is pressed => Led ON - Turn the led ON/OFF if the switch is pressed 04_button_led		via GIPHY
COUNT
Led and Switch / Load and a Digital Sensor : Count how many time the switch is pressed 05_counter	via GIPHY
DIGITAL SENSOR PRESSED ON/PRESSED OFF
Turn On the Led while the switch is pressed - 06_led_on_off		via GIPHY
ARRAY
Led Array and Switch / Array of Loads and a Digital Sensor: we control the amount of the Led based on the times we press the switch - 07_array_led_switch		via GIPHY

Power loads

Power loads = something that consumes more current than the current that the Arduino can provide.

Circuit driver

To be able to control power loads with the Arduino, we created a circuit driver. A circuit that allows you to control a Power Load with low Voltage (Arduino) but the Current for the Load in sinked by a difference source.

The circuit is composed by:

• A Mosfet N-channel - The transistor (an active component. Its behaviour changes based on the Voltage applied to one pin (Gate).)

• A Diode 1N4001 - In this configuration, it is called flyback diode. It is used to protect the mosfet.

Magnet - flip dot

• Create a coil. Wrap it 50/100times - Wrap the ens piece around the loop to secure the wire in a circle. - Burn off the enamel and solder the ends - test-it with the power source

via GIPHY	via GIPHY

Motion - SMA

SMA (Shape memory alloy) + high load circuit/code Resources

Inspiration

Flexinol 0.012", leather and Arduino heat controlling circuit from Afrdt on Vimeo.

PROCESS Flexinol

We teamed up, to prototype and experiment with one power load by team. I worked on SMA motion with Louise and Surzhana. First we tried to understand how Flexinol worked and tried to put it on boiling water to see how it reacted: it just straighten up, because straight wire it's the original shape. To better understand here is the definition of SMA:

• A shape-memory alloy (SMA) is an alloy that can be deformed when cold but returns to its pre-deformed ("remembered") shape when heated.

It's possible to a set a "remembered" shape to the SMA: So to give it a specific shape we need to traine the wire, so when heated to activation it returns to this specific preset shape. What does it mean? : To train the wire you have to give it the shape you want and heat it with a flamme in this specific shape during approximately 8-10min.

How to train the SMA?

How to train the SMA?

1. wind the cable around a screwdriver (for example).

2. keep it taut on each side

3. heat it over the flame of a **candle** for at least 8/10 minutes
(by heating the wire as close as possible to the flame - the blue part)

UNTRAINED	TRAINED

We wanted to try the an SMA smoked pleated pattern We draw the pattern and cut several small pieces of trained SMA wire to create the connections. BUT It is tricky to make a good connection as it does not stick to solder.

Another way is to crimp a small metal bead( You can crimp it together with small wire, or solder wire on the crimp bead (if it is made of material that stick to solder)

But we didn't have them. So we decide to make a loop and to further sew, embroider on top with conductive thread. (Which I realize is not the ideal way because when heated the wire moves, curl from the sawn stitch and then the connection is lost, creating a break into the circuit.)

At this point the flexinol work with one small part of the smoked pleated fabric.

But when we tried to connect it, the hole piece finished, it did'nt work (not with the battery or with the arduino)

We didn't think that a piece so large with so many flexinol , will need a battery with more current, and that we didn't had that in Oullin. So to make it work it needs to be more potent.

Results

Surzhana made a paper Hand and made it work

I then tried with small samples:

• on the left with untrained flexinol - on the right with a trained flexinol

UNTRAINED	TRAINED

• I got very inspired by the movement it makes as in my prevoius works I made textile move using manual motion: see bellow

Copyright ©CharlotteBracho | All Rights Reserved

And so I wanted to test with some pleated textile too.

I pleated a piece of organza silk, and trained a piece of flexinol. Sew the flexinol with conductive thread, and fixed with some copper tape just to get it a bit more attached as I do not Have small crimp metal beads.

VIDEO

useful links

Project The Culture Series by Afroditi Psarra and Dafni Papadopoulou https://vimeo.com/119051547 https://afroditipsarra.com/

Las year projects:

Patty Jansen

https://class.textile-academy.org/2021/patty.jansen/assignments/week10/

Sara Alvarez

https://class.textile-academy.org/2021/sara.alvarez/assignments/week10/

SMAs

SMAs Meet Smocking http://etextile-summercamp.org/2014/sma-meets-smocking/

SHAPE MEMORY ALLOY TRAINING

https://www.kobakant.at/DIY/?p=6682

More Smocking Examples from Kobakant

https://www.kobakant.at/DIY/?p=6687

How to work with Shape Memory Alloy by Jie Qi

https://makezine.com/2012/01/31/skill-builder-working-with-shape-memory-alloy/

about SMA

https://technologystudent.com/equip1/sma1.htm

Thermochromic ink

Thermochromic ink + heated circuit/code

So I tried the Thermochromic pigment. First I mixed the pigment with some white Woodglue. I put enough pigment so the effect will be more drastic. Then tested the painted textile with conductive thread and a battery.

process images RESULT video

NeoPixels

Then I tested some Sketches to control Neopixels:

Implementation	SKETCH	RESULT
STRANDTEST
Run a test - Example -> Adafruit Neopixel -> Strandtest		via GIPHY
NEOPIXEL 1
Control single/pixels - 01_neopixel_v1, 01_neopixel_v2		via GIPHY
NEOPIXEL 2
02_neopixel_full		via GIPHY
USE ANIMATIONS
Use Animations - 03_Wipe		via GIPHY
Use Animations - 03_Rainbow		via GIPHY
DIGITAL SWITCH
Trigger a sequence with the switch - 04_Wipe_sw and 04_Rainbow_sw		via GIPHY via GIPHY

Useful Links

Lecture

• Lecture of the week by Liza Stark

Tutorials

• Tutorial 1 – Emma Pareschi
• Tutorial 2 – Emma Pareschi

Other useful resources:

• Files Sketches
• Other

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Last update: 2022-05-14