This workshop is a part of a course at the Art Academy Weissensee Berlin. May7 – July 9 2020
The course took place as weekly online course. The hand book PDF is here >>
Meet the Material (May 14)
Building Textile Sensors: Digital
May 21
This week, we will build a digital sensor/ switches. Digital sensors have 2 states, 1(ON) and 0(OFF) while analog sensors have range of states like “half on” between on and off. The idea is simple. You have two conductors (conductive thread, conductive fabric.. or any material that conduct electricity) that has state of touching each other, or not touching each other.
Here is an example of finger switch. Conductors on each fingers are not electrically connected when your fingers are not touching each other, and when you close your fingers they contact and let the electricity go through.
You can think of body parts that you could detect two state: touch/not touch, and make this simple contact switch. It can be a finger tip and a palm to detect if your hand is open or not, or your upper arm and side of your body to detect if your arm is held up or down.
When adding conductive fabric to base fabric, one of the convenient/quick ways is to use fusible interfacing. It is sometimes called bondaweb, iron-on textile glue or vileceline. You will need an iron (or ideally heat press) to use it. The fusible in the material kit is from a company called Bemis.
If you do not have iron at home, and can not use fusibles, you can also think of other ways to add conductive surfaces on your base fabric. here are some examples. When adding conductive surface, you want to also consider the stretchness of your base material and choose which material and method suits the best.
Now, you can also try making fabric push button. This is a translation of common mechanical push button into soft fabric material. The idea is again the same. two separate conductors that touch when you push.
Here are more instruction >> https://www.kobakant.at/DIY/?p=48
You can make the button in any shape. You have to think about where your are pushing it, where the conductors should be placed, and how the spacer separates them to achieve two states. The tabs are made so it is easier to connect crocodile clips. If you are designing for specific embedded application, you may not need these tabs.
You can come up with designs of digital sensor/ switches. Here are some example of digital sensor ideas
Neoprene Stroke Bracelet >> detail instructions
Tilt Sensor >> detailed instructions
Button Switch >> detailed instructions
Building Textile Sensors: Analog
May 28
Now we try analog sensor. Analog sensors shows range of inputs, like faders or volume knobs on your audio devices. It has range of states. The introduced textile sensors change its electrical resistance. Instead of ON (no resistance) or OFF (infinitely big resistance) it has the range in between the two.
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If you remember the materials we sampled in week2, there were some highly resistive materials that had resistance changing properties. We use these properties to build a sensor. The challenge is to design a surface or an object that accommodate the resistance change when you interact with it. Here are some examples.
Textile bend sensor
Knit/Crochet sensor
felt pressure/bend sensor
and there are many more nice tutorials on felting techniques online. please check.
here are some sensor design that extends the introduced sensors.
felted crochet pressure sensor
You can try exploring these other sensor designs, or make your own sensor design.
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