Sensors come in many forms, you can buy them already manufactured, or make them yourself. 

The latter is my favorite for many reasons. This sensor is meant to be integrated in to wearable technology projects as an alternative to buying manufactured sensors which are made of rubber, metals, plastics and ceramics. My experience with a manufactured stretch sensor hasn't been good. It is one made of rubber with crimped metal hooks at each end. It broke easily and did not hold any properties found in materials that a wearable tech piece would mainly be constructed of; fabrics, thread and so forth. You can buy this conductive rubber in any length, but still, rubber isn't always the material you want for a project.

I've been experimenting with different ways of making soft sensors, particularly ones that utilize felting techniques. >>huge felt dork<<

This sensor is crocheted in a tube, it can be crocheted in a strip and other shapes. I myself have not tried these yet, but this is why I am sharing the technique!

This technique is a starting point and meant to be ran with.
Use this for any project you see it being applicable towards and please post them when you can, I would love to see what people come up with! 


Step 1: Tools You May Need

Required Tools

Crochet tools
* multimeter
* alligator clips
* scissors or any sharp blade
* merino wool yarn - Frog Tree brand worsted weight 
* crochet hook - size H/8 5mm
* conductive thread - Lame Lifesaver
* elastic thread - Stretchrite brand

Felting tools

* sushi mat
* towel
* soap
* cup of warm water
* access to a sink or a large, deep container filled with cold water (not pictured, I used a sink)


* measuring device
* needle nose pliers
* heat shrink tubing
* The pins from D-Sub connectors (male and female)
* Ribbon cable


* sushi mat
You can use many materials here that you can find at various kinds of stores. The idea is to get something that you can roll up you item in and that has a textured surface. Here are some suggestions:
   - tulle netting
   - carpet saver
   - placemats made of rubber or bamboo
   - bamboo blinds
   - bubble wrap

All of the required tools are ones that will guarantee a successful outcome. If you choose to change or substitute any of them the outcome may differ. Some tools are more exchangeable than others such as the sushi mat, however, even if you were to use the tulle netting instead of the sushi mat, you would need to rub the sensor with your hands rather than roll it back it forth as you would in a sushi mat or blind. So some material substitutions may take some finesse to work with.
The ones that will definitely make a difference will be changing the crochet hook size and gauge of yarn, I have tried some larger ones of both without much success. You are more than welcome to experiment, but please keep this in mind!

the yarn must be wool if you want it to felt! Merino is hands down the easiest and best for this purpose.


I'm so sorry to get to this so late in the game... but I would like to answer teaellen 2003 finally!<br>A sensor is a device that you can use to translate a physical action into an electrical signal. You can use sensors in circuits to gather data on in input and apply that data to any output you can think of given what tools you are using. Examples can range from musical controllers to assistive technology devices.<br><br>This sensor is a stretch sensor, it's electrical resistance lessens once the ends are pulled and stretched. A range is created by interacting with it, which can be read by a micro controller or computer and processed in many ways. You can also achieve low resistance by scrunching it up.
sorry but what exactly is a stretch sensor?
Very well done!
Spool knitting looks like it would accomplish the same thing....only faster!
ah yes... i feel very comfortable with the crochet hook in my hand, but you can definitely find tools to circular knit for you!

About This Instructable


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Bio: Specializing in sewing, soldering and snacking. More stuff I do... I teach an interactive fashion and textile class called Wearable and Soft Interactions at California ... More »
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