chebe: (StepIntoTheLight)
[personal profile] chebe
Three *years* ago I started this project. At a Christmas Jumper Make Night for charity. It seemed like a simple idea; sew up some LEDs with some conductive thread. The first year I only got most of the felt snowflake done. The second year I got the SewIO board wired up. It wasn't until the third year that I managed to complete the circuit. And there are problems, but we'll get to that.

This is the front of the jumper, a nice calming snowy winter sky theme. Decorated with felt cutouts, sequins, beads.



Winter Jumper
Photo by chebe



The central 'snowflake' has twelve blue LED sequins. And this is where we see the problem. They are extremely faint. And one of the spokes (i.e. two of the LEDs) don't appear to have enough power to light up at all.



Winter Jumper, LEDs lit up
Photo by chebe



This is the inside of the front of the jumper. That is the no-longer-available SewIO8 board that enables independent control of each of the spokes of the snowflake through use of only two pins on the microcontroller.

The black stuff is a fusible knit interfacing, which is being used here to stabilise the knit jumper under the central snowflake. To help it retain its shape under the weight of the components, and to reduce how much that section will stretch.

I wanted to try a new arrangement for placing the microcontroller and battery, to keep them as much out of the way as possible. Typically I've put them around the waistline and down the sides but found this both awkward to get at, and an area that heats up very quickly. I figured that since the neckline of tops are reinforced to limit stretching/losing shape, and that that area doesn't see a lot of movement/friction, it would be a good idea to try running the circuit there. The flat goldish strips are conductive knit fabric. There are four channels; power, ground, and two for controlling the SewIO8. I attached the conductive fabric with fusible tape, and overlaid it with fusible knit interfacing, but, as is to be expected, repeated stretching made most of the glue come apart. So I went along at various intervals with some groups of stitches. (This sadly left a visible puckering on the outside, so to try and distract from it I added the additional snowflakes, sequins, and beads.)



Inside circuitry, front
Photo by chebe



The four traces run to the Lilypad Simple microcontroller at the back of the neck (another region that seems to undergo very little movement/stress. Also reinforced with fusible knit interfacing. The conductive fabric traces are connected to the microcontroller with conductive thread.

Plenty of room and pins left available for adding additional components for interactively. But, in year four. Maybe.



Inside circuitry, microcontroller
Photo by chebe



Because I didn't fancy the chances of the felt of the snowflakes going through the washing machine even once I made it removable by using metal snaps to attach it to the circuit. (Also, ideally, to allow use of different seasonal pictures if the mood strikes. But the extra snowflakes mostly spoiled that idea.)



Outside connections
Photo by chebe



If you look at the back of the snowflake you can see (under white fusible knit interfacing) the positive and negative conductive thread traces that connect up the LEDs, and the metal snap connections.



Back of detachable LED piece
Photo by chebe



All in all, except for the faintness of the LEDs, I am happy to declare this project finished.

It was pointed out that most light-up jumpers are so bright that it can hurt to look at the person wearing them, so dimmer, softer, LEDs aren't actually a bad thing. Especially as this kind of jumper is typically worn in winter, in dark pubs. That is a very good point. I just wish it was intentional.



Winter Jumper, modeled
Photo by chebe

Page generated 2017-Mar-26, Sunday 01:37 am
Powered by Dreamwidth Studios