Galvanic Skin Response sensor

I promised Heidi some info about making a Galvanic Skin Response sensor, like the one I used to measure skin conductivity in the Greetometer Glove to test the sweatiness of the wearer’s hands.

I used the instructions and code on this blog post:
If you don’t want to use processing, you can just do a simple Serial.println() in the Arduino serial monitor.

And I made my own electrodes out of coins, like in the example:

In the final project I soldered crimping beads onto the coins.  They need to be polished now and then.

The cool thing about skin conductivity is that it indicates more than just humidity on the skin.  If you try the example in the link above and breathe in sharply (as if surprised) while testing, you’ll see a change in the readings.  Combined with other measurements (movements, heart-rate, etc) you can start to detect stress levels.

Sewing components

I was talking with Carmen about how to attach the piezo elements to the sound gloves, and we were trying to remember the name of an embroidery technique used to attach mirrors to saris.  Well, it turns out it’s “Indian Mirror Stitch” (duh) or “Shisha Stitch”.

Here it is in one of my projects:

Google “shisha stitch” and you’ll find all sorts of instructions and variations.

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blinking LED without delay()

Andy’s step sequencer was coming along nicely until he added a delay to blink his LED to visualise the tempo.  The delay would slow down the whole main loop, meaning that all other readings (like push buttons) had to wait for the end of the delay before they were activated.

Here’s Andy’s lovely breadboard:

It just can’t be possible that Arduino has such a fundamental flaw, can it?  Well, kinda, but it turns out the problem can be solved.  In fact, the solution was right under our noses…

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haptic motion communication

A few links about manipulating muscles with electric pulses…

Here is the Dutch artist I mentioned who experimented on himself:

An idea of how it looked:

His safety tips:

The device he recommends using is called a “TENS” device.  You can buy them on amazon!  This would be a great way to safely experiment with the technique throwing people off-balance.

social feedback garment

Today I talked with Heidi about the possibilities of getting fur to move or “stand on end”.  We thought it would be great to use the inherent properties of some fibres in combination with static electricity.  The thing about static electricity is that it is high voltage, so we have to be careful when combining it with wearables!

It would be great if we could achieve it in a more natural way.  Here is a webpage with a list of materials and their natural tendency to become positively or negatively charged:

Another possibility for research is electro-magnetic fields (EMF).  Are there materials that would respond to this, apart from iron powder?

(beautiful execution, requires lots of energy)

About group collaboration.

I thought it might be good to give you some hints to collaborate online with your group. There is a plethora of different ways to do this, and whatever you find that suits your interests best is probably best for you. And then best way of course is to see in Real Life.
Anyway, I have found out that google docs is a pretty nice way to sketch out ideas together. It allows many people working on the document at the same time, and with comments it’s easy to have discussions on the side. It’s a simple and obvious choice, but it works.
For mind mapping there is again many choices, but if you want free and online then mindmeister might be worth a check. On mac you can get some nice mind map software for free or at low price from the ac app store just by searching mind maps. They can even sync to your iOS device. I guess something like that exists too in the Android world.
Also when making the mind map and when you have some rough idea sketched, it’s good to start mind mapping the techniques you might need in your work. What kind of sensors/actuators I might need. What kind of programming this project needs. If your projects connects to the internet, then you probably need to do some web programming too, and that is good to notice and add to your work list. So when you have done mapping these, you have some idea of what is needed for your work and you can start learning and requesting these topics from us too.
So I hope these get you started and I’m looking forward to hearing from you.