Jacket Wiring, LED Setup, and Light Pipe Assembly.
I never took pictures of this process with the first prototype so I need to complete the second prototype and take pictures to use as visual aides along the way, I should have them up in another week or so. I may end up designing some nice 3d printed LED holders for mounting too.
First off we need to get the Light pipe set up. Measure the length of the light pipe and cut it into two equal length pieces. Press one end of the light pipe onto a piece of tin foil and cut out a small disk using an X-Acto knife. This disk is placed between the two segments of light pipe to prevent the signals from bleeding into each other from the opposite end, and act as a mirror to help brighten up the end of the pipe that lacks an LED. [In the future there are plans to experiment with dual LED terminated segments, along with additional pipe segments that can be programmed to operate in a different manner].
Cut an inch and a half length of clear heat shrink. Insert the Light pipe, aluminum foil disk, and other segment of light pipe. Center the aluminum foil disk in the middle of the heat shrink. Press both lengths of the light pipe and sandwich the aluminum foil firmly. Heat the heat shrink tubing with a blow dryer or heat gun(do not use flame as it could discolor the light pipe) to lock the light pipes and aluminum foil into position. Continue to apply pressure sandwiching the aluminum foil until the heat shrink has cooled.
Lay out the pipe on the back of your jacket in the configuration you see fit, making sure to keep the heat shrink tube centered in the middle of the jacket. Curves are acceptable, just try not to have any tight radiuses so the light will continue down the pipe well. You can get a bit creative here. The only point to remember is the more light pipe used, the dimmer the pipe will end up becoming towards the middle when the segments are longer than around eight inches(depends on curves and LED brightness).
Attaching the light pipe to the jacket is still a work in progress as far as trying to find the best method. Currently I am using some 100lb test fishing line and sewing it into the jacket about every inch and a half, then using super glue to lock the knot and seal the holes in the leather where the fishing line penetrates. This is not the easiest method since puncturing leather in general is a difficult process but it does work and I have not had any issues yet with it failing to keep everything together. I eventually would like to find either light pipe that has a sewable welt along the edge or some clear sewable hollow piping that the light pipe can be pressed into.
Locate an inner pocket in the jacket where you would like to have the headphone jack come out at. Next locate the two points where the light pipe terminates on the jacket. Determine the best path from each end of the light pipe to the pocket. You will need to route a length of 24 gauge speaker wire from each light pipe end into the pocket, I found using a piece of stiff wire to push from one end to the other and then using it to pull the wire through the jacket saves a lot of time and energy. Leave enough length on both ends for trimming, and to pull the jack out from the pocket to easily plug in the module.
At this point determine which legs of your LEDs are positive and negative to prevent issues and confusion as you solder up the wiring and resistors.
If you have standard resistors instead of SMD resistors, it is easiest to solder them into the headphone jack. Cut them short and solder one each to the left and right leg. Slide the headphone jack cover up the wires. Next slide a length of heat shrink up the wire coming from the right side of the jacket and solder the wire to the right headphone jack leg. Do the same with the wire coming from the left side of the jacket on the left headphone jack leg. Finally solder both ground wires from each side to the ground leg. Slide the headphone jack cover down and screw it in place. At the light pipe ends solder the ground and positive wires to each LED.
If you have SMD resistors it seems to be easiest to solder the wiring directly into the headphone jack, we will use perf board and create a mount for both the LED and resistor at the light pipe ends. Cut the perf board to approximately a 3x3 hole square. Solder the 4 legs of the LED in place, then solder the ground wire to the negative side of the LED. Next solder the SMD resistor down to the board at the positive LED end, and solder the positive wire to the SMD resistor.
At this point it would be a good idea to plug the module into the headphone jack on the jacket and test to ensure the LEDs are lighting as expected. You can do this by either connecting with the bike module and pulling the break/using the blinkers, or by connecting the jacket module over bluetooth to a computer and using the arduino console to send "HH\n" to the module(excluding the quotes).
Eventually I want to design some 3d printed LED holders for mounting that will hold the LED securely and capture the end of the light pipe, they will also provide some points for sewing down on the jacket as well. Until then I am using more heat shrink tubing. Cut an inch and a half length of black heat shrink tubing and slip it over the LED far enough to cover some of the wire as well, then slip the other end over the light pipe. Press the LED to the light pipe firmly making sure the pipe is centered on the end of the LED. Heat the heat shrink tubing with a blow dryer or heat gun(do not use flame as it could discolor the light pipe and damage the LED) to lock the light pipes and LEDs into position. Run a little superglue around the wire and heat shrink to ensure a watertight seal, the light pipe and heat shrink should seal up nicely by its self. Push any excess wire back into the jacket and then superglue around the wire to prevent it from pulling and damaging the LED and to seal the hole. Finally Run one last stitch of fishing line over the ends of the light pipe where the heat shrink is, and superglue from the fishing line back to the end of the LED within the heat shrink tubing.
I know the superglue concept does not sound as appealing on a motorcycle jacket as you would imagine, but it works extremely well with the leather. If you use a careful hand so as not to allow for drips the superglue is not noticeable in most cases. The fishing line can be seen slightly if someone is inspecting up close so aesthetically it is not the best but it works quite well without blocking any light emission from the light pipe.
Again, sorry for lack of images on this section, I will work to get some pictures made and added soon.