The Atmel-based LilyPad Arduino – designed by Leah Buechley and SparkFun Electronics – is targeted specifically at wearables and e-textiles.
The platform, powered by either the ATmega168V (the low-power version of the ATmega168) or the ATmega328V, can be sewn to fabric and similarly mounted power supplies, sensors and actuators with conductive thread.
Recently, a Maker by the name of Duniken created a sensor demo mat for the LilyPad and posted a detailed description of the build on Instructables.
“I wanted a place where I could experiment with the different sensors, but also something that I could use to show examples of what can be done without constantly uploading code,” he explained.
Key project components?
- 1 x ProtoSnap – LilyPad Development Board (kit) which includes the following:
- 1 x LilyPad Simple Board
- 1 x LilyPad Button
- 1 x LilyPad Slide Switch
- 5 x LilyPad White LED
- 1 x LilyPad RGB tri-color LED
- 1 x LilyPad Light Sensor
- 1 x LilyPad Temp Sensor
- 1 x LilyPad Buzzer
- 1 x LilyPad Vibe board
- 1 x LilyPad FTDI Basic
- 2 x Conductive Thread Bobbin
- 1 x Needle Set
Duniken also used:
- 7 x sewable snaps
- 1 x Piece of fabric big enough to hold all of the sensors
- 1 x Fabric Marking pen
“Although I had the LilyPad Development Board, I decided to use the LilyPad Simple Board so I could use the extra pins as switches,” he clarified.
After drawing up a diagram using LucidChart, Duniken arranged the sensors and switches on the fabric, using the marking pen to indicate where each pin and component would be placed.
“I removed the sensors and used the marking pen to draw the circuit onto the fabric with a ruler to make sure all of my lines were straight. When I had the lines drawn, I again placed the sensors on the mat to make sure that everything lined up the way I wanted it to,” said Duniken.
“I ended up changing the position of the RGB light slightly so the lines were less likely to make contact with the other pins on the LilyPad. I wanted the lines to be part of the final piece so, once I was satisfied with the diagram, I traced the lines with a permanent marker. If I did it over, I would probably color code the lines so that it can be better used to explain how the circuit works.”
Next, Duniken cleaned off the marking pen, stitched on the sensors and other components, sewed the circuits and sketched the code.
“To ensure that the sensors stayed put while I sewed the circuits, I did a quick stitch with plain thread to hold the components in place. Using the conductive thread, I sewed along each of the circuit lines connecting the different components to the LilyPad,” he added.
“Be careful where the Positive lines (red) cross the Ground lines (black). I used a small piece of plastic cut from the LilyPad packaging to make sure that the lines didn’t short. I used hot glue to tack down the plastic so it wouldn’t snag on anything.”
Interested in learning more about designing your own Arduino Lilypad Sensor Demo Mat? You can check out the project’s Instructables page here.