Last Monday morning we went across the hall to the MILL (Make Innovate Learn Lab) to make paper circuits as a class. It was the first
time I created a paper craft with an embedded electrical circuit. It was pretty fun to play and make a circuit using copper tape, small lights (i.e. LEDs), and a coin battery. So here we were in the MILL, around a table with all the materials available to start a project. The instructions were to make an electrical circuit on a piece of paper, mounting LEDs to light-up a greeting card, an origami animal or a 3-D pop-up sculpture.
At the beginning I did not know exactly what to make with the materials in front of me, so it took me a few minutes before finally deciding on making a small coloring book for my daughter. My idea was to draw in each page an animal or funny character whose eyes would light up each time the right bottom corner was pressed (that corner is where I placed the coin battery).
From previous experiences with LEDs and circuits, I knew how I needed to connect the anode ("+" positive end) and cathode ("-" negative end) of the LEDs to the corresponding positive and negative terminals of the battery coin. The first thing I did was to place the LEDs and battery on the last page of my "book-to-be" to plan how much copper tape I would need to use (Figure 1). I knew that two LEDs would light up only if they were connected in parallel, not in series, because the current would not be enough to light up the second LED. So to make sure I connected the LEDs correctly, I drew a small diagram on a piece of paper so I could identify how I was going to connect the two LEDs to each other (Figure 2). Based on that drawing, I decided not to use copper tape to connect the two LEDS but to directly wire together the anode and cathode (Figure 3) and wrap each of the positive and negative terminals with the copper tape all the way to the positive and negative terminals of the coin battery (Figure 4).
The next phase was to decide what to draw on each of the four pages so I drew some faces of baby animals that found on the internet. For the first page, I drew a tiger with the bright red LEDs, a pig, and a giraffe (Figure 5). The second page shows a monkey with "bananas" (one of Claire's first words before knowing how to say "Papi", "daddy" in Spanish) (Figure 6). The third is a chick eating corn (Figure 7) and the last page is a dog (Figure 8).
I was able to help troubleshooting and show others how circuits work. A couple of friends were having problems making their circuits to light up because they had their terminals switched or the copper tape was touching another piece of copper not closing the circuit. These troubleshooting practices helped us to learn the concepts as we went about testing the position of the battery, the connection of the tape, the polarity of the LEDs, making sure the circuit was closed with no gaps, etc.
It was a great example how such a simple project allows someone to learn concepts in circuitry like polarity and parallel versus series, design of paper crafts, even thinking how to place the hidden circuitry. At the end of the project I asked myself why in the world did I pick RED LEDs to make a "cute small book for a baby girl"? Those baby animals looked freaky evil animals haha.