5. E-Textiles and Wearables I#
Sensor Book#
For this weeks assignment I wanted to create a Fabric Sensor Book for the Dassault Systemes Lab. Since this is the first year Dassault Systemes is participating in the Fabricasdemy I thought It would be a great time to create a sensor reference book for anyone interested in the different sensor possibilities when using fabric. It would be irresponsible of me to continue without sharing where I gained a great amount of inspiration from. During my research on the different sensor types I stumbled upon EIT ICT Connected Textiles’s Interactive Knit Book. The Interactive Knit Book demonstrates examples of knitted electronic elements such as switches, sensors, speakers, and heat elements that cause color change. I found the book itself aesthetically appealing and very informational.
ANALOG SENSORS: Pressure Sesnor#
How Pressure Sensor Works#
In general pressure sensors are fairly easy to construct. The pressure sensor consists of a sandwhich made of two conductive fabric sheets with a resistive (anti-static) fabric/foam/plastic between the conductive fabrics. The two conductive sheets are then connected via conductive thread or in my case copper tape. Copper tape is also use to build out the circuit.
Materials and Parts#
• LEDs • Anti-Static Foam • Woven Conductive Fabric -20cm Square • Copper Tape • Felt (Non-Conductive Fabric) • Fusible interfacing • Magnets • Regular Thread
- Prepare Materials and Laser cut The first step I took was deciding the shape of my pressure sensor. Since I plan on putting the sensor in a book, I chose the safe shape of a square. Before cutting your fabric take into consideration the size of each layer. The outer layer, non-conductive fabric should be the biggest in the sandwich. Second comes the resistive fabric/plastic. The reason for this is because you don’t want the conductive fabric sheets to touch each other at any time. Finally the conductive sheets should be the smallest.
Felt : 4” x 4” square Anti-Static Foam: 2.5” x 2.5” square Conductive Fabric Sheet: 2” x 2” square
- Ironing on (Fusing) With all the shape cut out the next step is fusing the conductive sheets onto the felt. This is also a good time to create the connections of each conductive fabric. From what I read the best method for this is soldering conductive thread but at the time there were no solderable conductive thread in the lab. Instead I used copper tape to create the connection and they worked pretty well.
3. Sewing
I sandwiched the anti-static foam between the two pieces of fabric fused with the conductive fabric, so that the conductive fabric faces inwards , towards each other, separated only by the anti-static foam. I used one of the sewing machines in the lab to close the sandwich and secure each component in place
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Sketch out the Circuit and Page Layout
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Construct Book Page The electrical traces of the circuits are made from copper tape that has been applied to the inner side of the pages. Windows cut in the flap of each page show the various elements of each circuit, without showing the connections between them. Each page can be easily folded open to reveal the behind the scenes circuitry. Pages are laser cut and engraved
DIGITAL SENSOR: Tilt Sensor#
How does a Tilt Sensor Work#
Is a circuit with a heavy metal bead strung on conductive thread and surrounded by conductive fabric drops, makes for a simple four way digital tilt switch. When the metal bead makes contact with one of the petals it completes the circuit to an LED light, causing it to light up. This very simple technique for detecting direction of tilt can be used in many different ways and variations, and this swatch aims to illustrate the basic functionality of the design.
Materials#
Conductive fabric ( Stretchy and Non Stretch) Base fabric LEDs Conductive thread Coin Cell battery Metal Bead
Steps#
- Gather Materials
- Cut + Prep Shapes
- Glue on conductive contact areas
- Create + Stitch Batter Pocket
- Stitch (Positive +)
- Connect Metal Bead
Files#
Page Design(PDF)
Right Click to Save as PDF