Week 13 ~ wildcard week


Laser-induced Graphene (LIG) origami

I really enjoyed this week, learning about a really cool process on one of the most 'basic' fablab machines. Many thanks to Wedyan Babatain for the great intro to the process and support during the week.

I was intrigued by the ability of adding electrical properties to a material as part of a classic fabrication/cutting procedure.

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The zig-zag LIG capacitive sensor before folding. The scoring of the folds worked surprisingly well - I reduced the power ~50%, so it didn't cut all the way through (still generated a thin LIG-like line though!)
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Zig-zag sensor after folding.
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LIG flakes of the first test under the analog microscope ...
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LIG flakes of the first test under the digital CBA microscope
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Engraving LIG pads on the faces of a Miura-Ori origami crease pattern.
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LIG pads after engraving, some slight flaking in the right corner, perhaps due to uneven base plate/uneven adhesion.
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Applying conductive-adhesive copper tape to allow soldering and measuring the resistance of the pads - very consistent, all aound ~480-500 ohms.
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Applying a second layer of polyimide film (thinner and mildly adhesive) to protect the LIG layer.
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Folded Kapton/LIG origami and earlier test pieces. The folding did not work very well - talking to Ozgun briefly, she mentioned perhaps trying PEI/Ultem sheet as an alternative that might be more compliant/foldable. Another alternative might be to make a hybrid material, where the hinged parts are replaced by another material/fabric (or perhaps the second layer is only applied selectively to the faces), but part of the appeal of LIG for me had been the ability to have a single fabrication step that combined mechanical and electrical function. In any case, I would love to explore this space further.
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Testing the second zig-zag sensor (also with copper tape and second adhesive Kapton layer applied, as for the origami test): I couldn't get significant readings through the set-up I had from inputs week, but may just require playing with the resistor values/trying Neil's AC-based 'step-response' method instead