Addressable LED Hoop Earrings

Backstory:

I love putting LEDs in and on things, and I am also a jewelry artist. It was only a matter of time until I squished the two things together. A year ago I made a functioning prototype of what I'm going to show you today, but as many good projects, the prototype was clunky, funky, and mostly in a drawer all year. Then came the Hackster.io Junk Drawer Competition. An excuse to clean 'er up that I couldn't pass up.

The Build and the Build Challenges:

There are a few challenges in this build. One, it's small! This means small LEDs, small wires, and small connectors. Another big challenge is that we need our super blingy, very bright, very addressable earrings to get enough power, and that power needs to be stored somewhere. As a last challenge, because I have to be extra, I wanted the shape of my earrings to be custom shaped stars.

The Solutions:

So, good news, I designed my way through all of these challenges. My prototype ended up using a tiny, addressable 2020 LED strip, a Pixelblaze Pico LED controller and an 18650 battery. The battery is on a hair clip and clips on top of a ponytail, kinda like a bow, but more powerful.

I also used mainly standard sized JST connectors and 22 awg silicone wire.I updated this basically functioning prototype with a re-wired 18650 battery holder to make the package much smaller and more elegant, and used almost entirely mini JST connectors with a re-structured wiring harness so they hang better.

I upgraded to 30 awg silicone wire, and longer lengths. I made the acrylic stars bigger, and used shinier acrylic (the star shaped hoops are made out of star-shaped holographic glitter! Isn't that what we all want in all of our projects?)

A last useful design decision that I made is to make most of the components detachable from each other. This helps with troubleshooting, or updating parts later. That's why we use so many JSTs!

Put It Together:

The Hoops:

First, lasercut your earring shapes if you are going to custom make them.

The LEDs and Wire:

Next, if your tiny COB led strip came with a connector, desolder that connector. Strip and solder new wires on using that 30 awg wire. Make the wire long enough to run from the lobes of your ears to around the mid-point of the back of your head. Give yourself a bit extra, you can always pin it out of the way later, and the braid will make the wire shorter.

Once they are securely connected (Bonus! Test your connection with jumper wires connected to a controller and battery if you have that handy), mark each wire so you know which is power, which is data and which is ground. You can do this with different colors of tape. Mark the wire at the end, not the start, so that you know which wire is which at the end of your braids.Braid the wire. I use a standard three-stand-braid. Leave that ~1/2 inch extra on the end.Once you reach the end of your braid, use a small bit of heat shrink around the braid to keep it all together, so it doesn't unravel.

Next, peel the paper off the back of your LED strip and use careful dabs of hot glue to adhere the LED strip to the outside of your hoop earrings. This process is tricky, be careful! The glue gun is very hot, and this is delicate. Take your time. Once the star is covered, clip the end of the strip, and make another just like the first!

The final part of the hoop + wire part of the earrings is to solder micro JST connectors on the end of the wires you just braided. If you clearly marked your wires you should know which wire goes to which pin.

This part is tricky. Take your time, double check your wiring, test as you go if you can.

As a final touch, run a bit of heatshrink down around your braided wire, and onto the top of the star. This will cover the solder joins at the start of your LED strip.The Battery and Battery Holder:Now, get your battery holder together. I re-worked the wires on my pre-bought 18650 battery holder to make the package more compact. It came with a switch, I've just shortened the power cables significantly and glued the switch down. You don't have to do this, but it will make wearing these easier.

Hot glue your hair clip on the bottom of your battery holder. I like these jaw-style clips for this. If it doesn't want to stick, feel free to try other adhesives, or sand the bottom of the battery pack and the top of the clip.

The LED controller:

For the Pixelblaze Pico LED controller, I've soldered two 3-pin micro JST connectors to the pins on the board, along with a 2-pin standard-sized JST to connect to the battery pack. I use a small zip-tie to keep the wires coming off the board stable and tidy.To set up the LED controller through Wi-Fi you can use the excellent documentation in the Pixelblaze set-up guide.

Then I use a piece of wire poked through the battery holder to keep the controller attached securely to the battery package.

Finally, connect it all together!

Add Jewelry Findings:

Add a jump ring and ear hook so you can actually hang these from your head! You can scavenge findings from earrings you or a friend already has, or use specific stuff.You might need to poke holes in heat shrink if you have heat shrunk the tops of your stars. A safety pin works fine for this.

Important: This project is NOT intended to only be for folks with ear piercings. You can connect the stars to findings called clip-ons! Clip-ons make it possible for ANYONE to wear earrings!

Last but not least, try them on!

Final Tips:

- Important: The battery holder used in this project does NOT have reverse-polarity protection. Be very careful when putting your 18650 into it's holder, it will not be happy if you put it in backwards, and might melt!

- Use bobby pins and hair clips to place the braided wire where you want it.

- Brag to your friends and send me pictures! I would love to see other takes on this build.