How to Implement

Part 1 - Build Simple Circuits

• Each girl will create her own e-cuff.
• Pass out the coin cell batteries, holders, and LEDs. Point out that one side of the battery is positive and the other negative. Have the girls locate the positive and negative sewable tabs on the battery holder. They will need to sew from a positive tab on the battery holder to a positive tab on the LED. They will notice that there are two sets of conductive sewable pads: they can sew another LED to these or just tack them down onto the cuff with nonconductive thread.
• Make a simple circuit. Pass out the LEDs and test leads with alligator clips, then have the girls make a simple circuit. Why did the LED light up? (For their LED to light, electricity must travel from one side of the battery, through the wire to the LED, and back through another wire to the opposite side of the battery.) This is called a complete, or closed, circuit.
• Introduce conductive thread. Explain to the girls that they will be creating a fashion accessory that lights up by sewing a circuit made of conductive thread. The thread will replace the test lead from the simple circuit because it is coated with metals, such as silver, copper, tin, and nickel, which are conductive. Compare the thread to the copper tape from the Chibitronics activity and the wires from the motor from the doodle bot activity in the robotics strand.

Part 2 - Prototype a Soft Circuit

• Brainstorm. Explain to the girls that they will be creating a circuit for an e-cuff. Have them brainstorm and sketch some ideas for what it might look like in their design journals.
• Plan circuit design. Have girls decide where they want to place the LEDs on the e-cuff.
• Pointer: The LEDs in this circuit are connected in parallel, meaning the electrical current splits and flows through all LEDs simultaneously.
• Lay out the design. Have each girl measure and cut a piece of paper of the appropriate size for her wrist. Lay all the components (battery holder, LEDs, snaps) onto the paper and mark the circuit onto the paper to make sure everything fits.
• Cut out the felt. Have each girls use their paper template to cut out a piece of felt. Lay all the components on the felt as shown (sample image). Have them mark the circuit directly onto the felt with a permanent marker or a fabric marker. They need to make sure that the lines of their circuits don’t cross or they will create a short circuit—which could cause the battery to burn out and is a potential safety concern. Refer to the LilyPad basics section of the LilyPad Sewable Electronics Kit Guide.
• Test circuit design. Have girls add a battery to the battery holder and test out their circuit. Then, have them use alligator lead clips to make a test connection between the battery holder and the LEDs.

Part 3 - Sew a Circuit

• Next, the girls will sew all the components of their circuit to the felt.
• Tell the girls to start by stitching the battery holder in place with the conductive thread. Start with the positive sewable tab on the battery holder, sew through the tab and the felt at least three times to make sure it's secured firmly.
• Continuing with the same piece of thread girls should sew the along their pattern.
  • Sew the LEDs on the positive side only making sure to go around the each sew tab at least three times. Use a simple stitch, such as a running stitch to connect all the positive tabs of the LEDs. Make sure the stitching shows on both sides of the felt.
  • Once they get to the last LED they should knot the thread.
• To connect the negative sides of the circuit repeat the steps above starting at the negative sew tab on the battery holder and connecting all the negative tabs on the LEDs and knotting the thread at the end.
• Girls should trim the thread ends as close to the knots as possible. Warn them not to let any thread cross between the two sew tabs of the LED—this could create a short circuit!
• Test. Have girls test their design by inserting a battery and flipping the switch on the battery holder.
• Tell the girls to make sure all loose ends are clipped so that the circuit doesn’t short out. You can seal the ends with clear nail polish (or colored nail polish if it is part of the design) to secure and seal the knots.
• Get Creative. Once the LEDs are working, have the girls sew snaps, lace, beads, and felt onto their e-cuff, using regular thread. If they don’t finish in the allotted sessions they can return to it later.
• Debrief. Let girls model their finished accessories for the group. Discuss which parts of the project were most challenging. Why? If they were going to do the project again, what would they do differently?