Author(s) : Martin De Bie
The idea is to create a non-woven homemade piezoresistive material. By using the technique of making cotton paper mixed with graphite powder, i manage to create a piezo resistive material which can easily replace expensive material like Eeonyx. This process is the continuity of an experimentation made with students (Céleste Teikiteetini and Jules Lobgeois) during a workshop that i lead.
To show the capabilities of this material, i integrate it into a simple circuit with led where it would play the role of simple pressure sensor for the swatchbook exchange of the summer camp eTextile 2016.
Ref/inspirations :
Pulp-Based Computing by Marcelo Coelho
http://www.cmarcelo.com/pulp-based-computing/
1- Material
– water
– cotton
– fabric
– paper
– graphite powder
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2- prepare paper pulp
Cut cotton, paper and fabric in small piece and put it inside a bowl of water. Leave it like this during 48h at least.
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3- Make paper pulp
Use a blender to mix your paste into something homogeneous.
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4– Add graphite
Add into your paste graphite, the proportion depends on your tests. In my case, i put 4 big soup spoon for 800g of paste.
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Mix it together with a spoon until you get a very black paste.
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5- Prepare your graphite pulp
Put your mix inside a big container and add a lot of water. Your mix need to be dilute to make your paper.
I use a frame that i’ve build with regular tulle attached to the wood.
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6- Make a sheet of paper
Dip your frame and take it out from the water quickly to catch pulp to create your sheet.
Apply your sheet on a piece of felt to absorb the water and let it dry.
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You can try to add together different layers of paper to increase the thickness of the sheet and the resilience of the matter.
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