I needed an easy to build circuit board that was kid friendly so I designed a simple paper circuit. The design consists of laser cut paper templates that are wired up using copper foil tape. I decided to start off with a few basic electronic elements including batteries, resistors, LEDs and switches. I could have used solder-less prototype boards however my experience suggests that the parts tend to get lost. To avoid this problem I pre-mounted the components on small paper circuit boards that I had the kids assemble. The brightly coloured paper makes the parts easy to find and has the added benefit that I can label the components.
1. In the first lesson I took ten minutes to describe the basic circuit and how to assemble the copper foil onto the paper circuit boards. The foil is applied so that it covers the template etched into the paper. Once I had explained this the children were given about 30 minutes to cut foil and tape the foil to their circuit board. I had the kids initial there work and collected all of the parts.
2. Between lessons I soldered the components to the copper foil. At our next meeting I will review the design of circuits and explain the symbols and ohms law.
a. Circuits must be closed for current to flow
b. What happens to the LEDs brightness if I add a resistor to the path
c. Does the order of component layout matter?
d. Why don’t 2 LEDs in a row work?
e. Why can you power the LED with a coin cell an no resistor?
f. What would happen if I used AAA batteries?
g. How much current flows when the resistor is in the circuit?
-Mount the switch on the back side of the paper circuit so that the laser cut symbol is visible. This means extending the copper on the back side of the paper board.
-Create a template for cutting the copper foil. This would result in much better reproducibility of the design.
-Create a set of origami instructions for folding the copper foil.
-Cut a hole for LEDs to simplify soldering
The template for the laser cutting was captured in Inkscape and is available here. Childs_Play_AssemblyV4