Birthday Cards

AmandaCardDrawandEagleWith April arriving birthdays abound so I decided to personalize my cards using copper foil circuits. The concept was simple; have a card with coloured balloons and a gift. Each balloon would be backlit with colour LEDs while the gift itself would be a Tiny44 circuit running Arduino code. The RGB LEDs on the Tiny44 circuit would fade in and out to make the present look more inviting. To start the project I sketched the card and scanned the sketch into Inkscape where I added the balloon details.

The next step was to export the drawing as a bitmap file so that I could use it as a guide for laying out the circuit. I imported the bitmap into Eagle using a user language program. The template allowed me to position the LEDs in the correct spot relative to the image. I used 12 LEDs in the design so I Charlieplexed them so that each of the 12 LEDs was bit addressable and only required 4 I/O. With the circuit layout complete I exported the design from Eagle as a pdf file that I could open in Inkscape.

AmandaFoilI redrew the layout in Inkscape using the Eagle pdf file as a guide. This allowed me to layout the pattern in an easy to use design that could be printed and used as a guide for laying down the copper foil. I added a little text as a build guide and printed the design on my laser printer. With the design in print I glued down foil tape to complete the circuit. Once all of the foil is in place I touch solder the joints and solder the LEDs in place taking care to keep them oriented in the correct direction. The Tiny44 board was programmed and soldered in place. At this point I tested the complete circuit.

AmandaCardLaserCutNext I created a template of the artwork that could be laser cut in 1/16″ matte board. The balloon segments become window boxes; as well, I cut a hole for the Tiny44 circuit board. The laser cut matte board is then glued to the foil circuit leaving the LEDs exposed in the laser cut windows.

FinalCard3inch To finish the card I printed and coloured the top layer of the card and glued it on top of the laser cut matte board. There you have it, my first laser cut, foil circuit running Arduino sketch.

Leave a Reply

Your email address will not be published.