Sprite Lights: LED Body Art

Overview

The Sprite Lights project started back in late 2017 and was a rally cry to blend technology with art. So many sci-fi novels, movies, comics, and more feature worlds and characters with body modifications. And while that sounds cool, we’re a long way off from that future.

So how do we create new and innovative ways to express ourselves with today’s technology? How do we blur the lines between electronics and art?

This question is how Sprite Lights was born. Created by me, Katherine Connell, it has taken winding and endlessly curious path and the project continues to evolve to this day.

Early Prototypes

My earliest prototypes used liquid liquid latex painted in layers onto a plastic sheet. While the final layer was tacky I'd lay out tiny SMD LEDs and let everything dry. From there I'd hand solder super thin copper wire to create the circuit:

Reusable Skin

It became clear over time that the latex skin was not going to be a viable option for how to adhere Sprite Lights to a body. It was fragile, required knowing how to do FX makeup applications, and there was the whole latex allergy issue to consider. I needed something more durable...

So I bought a 3D printer, learned how to model in Fusion360 and went down an entire borough (not just a single rabbit hole) of experimenting with extremely thin 3D printed skins. I tried just about every flexible filament in the consumer market.

But no matter how hard I tried, they just weren't what I was looking for. They'd look okay on light colored skin, but not great on dark colored skin. Also how the heck was I going to incorporate the electronics into them? After much experimentation I landed on....

SILICONE SKIN!

The silicone skin is made from hypoallergenic silicone rubber, pressure sensitive adhesives, and contains no latex. This serves as the backing to Sprite Lights.

If it’s dirty due to dust or other small debris it can be washed in warm water to rejuvenate its stickiness. Additionally, the medical grade adhesive is gentle enough that it will not hurt or pull out any hair when removed, but is strong enough to resist sweat and stay in place for hours.

Fun Fact: The adhesive is the same stuff that is used on adhesive strapless bras, and when moved homes I affectionally labeled the box it was stored in as "boob glue."

Late Stage Prototypes

With the silicone skin figured out I could now focus on the blending of electronics with the artwork.

Flexible Circuits

For the circuit boards I began prototyping using heat resistant PVC sheets and copper foil.

Currently, I cut the copper and PVC using a Silhouette cutter, and then with transfer tape move the copper onto the PVC. I then use solder paste and a home made stencil (made from a transparency sheet) to apply the paste and then place the LEDS and resistors using teeny tiny tweezers.

Lastly, I heat up the solder paste using a toaster oven or low temperature griddle to create the solder joints. Have no fear, I do not heat up the battery components in this way, those are hand soldered as needed.

Future aspirations include printed circuits (either by machine or screen printing) with conductive ink, however I currently do not own the tech needed to print circuits and small scale orders of conductive ink are very expensive.

I was able to get a sample of some conductive ink and had some early success for this method.

Artwork

Do you know the only thing in the ENITIRE world that silicone likes to stick to? If you guessed other silicone, you're correct. This meant I couldn't do use any kind of traditional medium for the art and the only thing it could be made out of was silicone. I would 3D print molds for the outline of the silicone artwork, pour the outline in black and background with clear, and then hand paint the artwork using slow curing dyed silicone.

This method was and remains very time consuming and yields more bespoke pieces:

Recently I've begun experimenting with screen printable silicone which would drastically cut down on production time. Additionally, it would allow pieces to be mass producible with consistent results and quality:

Original Artwork

Most of the prototypes created have used stock art (bought with a personal license). This was done so I could focus on the engineering and rapid prototyping phases. The intent of the final product will be to use my own artwork like the crane I created to make the Sprite Light in the key image of this project:

And this cool octopus tentacle I also made:

Or to do ✨collabs with other talented artists✨ to adapt thier art into a beautiful piece of light up body art.

Experimentation with Flexible Circuits

Flexible circuits, especially CLEAR flexible circuits are still in the early days, and not very accessible to home makers. Also, are they ever truly flexible?

A fun pathway I headed down was looking at material for the circuit traces themselves that offered ultimate results in being stretched, flexed, twisted and pulled.

Through endless hours of googling I stumbled upon this tutorial led by Steven Nagels, Raf Ramakers, Kris Luyten, Wim Deferme:

I was absolute fascinated and began experimenting on my own. Unfortunately the materials used in the tutorial were largely only available in the UK and I didn't have a ton of drop on ordering the US options for Galinstan, the metal that is non-toxic and remains liquid at low temperatures.

So I did what any maker does, and taught myself how to make it:

The biggest challenge for this method has been getting the Galinstan to "wet" or "stick" to the silicone. I've tried various priming methods and even contacted Steven Nagles for advice, but haven't quite cracked this one. This however remains one of my favorite methods I've explored, and whenever playing with it I felt like I was legit living in the future.

ASCA Organic Solar Films

One of the biggest challenges preventing Sprite Lights from being completed has been power and charging. I've never landed on a solution I've been fully satisfied with.

Coin cell batteries provided the low profile footprint I wanted without needing a complicated charging circuit but it felt wasteful and it's super hard to "hide" the battery. I could order ultra-thin custom made LiPoly batteries and integrate them, but I never really developed a charging system and methodology I liked.

ENTER ASCA ORGANIC SOLAR FILMS!

Imagine a Sprite Light where the the artwork IS a solar panel accented by LEDS. Featuring beautiful artwork you can wear during the day as it charges and by night it turns into a stunning piece of light up body art.

Alternatively, I could incorporate a semi-transparent solar filmalong the edge of a Sprite Light which may allow for more color and design options as the artwork would still be silicone. Another option would be having the solar film as part of the base layer with the Silicone Skin. There are a lot of different ways to explore with this.

I don't have a prototype created using these yet but I think this is the answer to my power and battery challenges I've had. I'm excited about an eco friendly, sustainable option that continues to blend the lines between electronics and wearable art.

Remaining Challenge

Embedding circuits into silicone remains challenging as I do not have access to pick and place machines, flexible and easy PCB fabrication, and other industrial materials that would make my circuits more resilient. My hand made circuits are prone to breaking due to this issue and need to be handled with care. However, I think with access to manufacturers to assist in production this could be easily overcome.

Notable Moments

San Diego Maker Faire 2018

The San Diego Maker Faire in 2018 event was the first time I had ever shown anyone Sprite Lights outside of my friends and family. I spent two days with my table absolutely swamped with excited makers wanting to hear all about my project. I talked so much I lost my voice on the first day but kept on talking the second day all the same.

I won a blue ribbon that weekend, but this wasn't just one of the best moments for Spite Lights, it was personally one of the best moments in my life. Seriously, it's up there with getting married to my best friend.

Arduino Internet of Things Challenge

During one of my prototype phases I was using an Arduino Nano to run and program an LED matrix version of Sprite Lights, so I entered the Arduino Internet of Things Challenge run by Arrow and Indiegogo.

I had NO IDEA what I was doing, but somehow I made it to not only the semi-finals but the actual finals. I was the ONLY female maker in either of those rounds, and my project went on display for final voting in the Arrow boot at CES.

I didn't win, and honestly I probably wasn't READY to win. But what a ride!

About Katherine “Smalls” Connell

There’s a family joke about my being created in my parent’s garage using the greatest technology of the early 80s. Hence the various online handles and nick names of TheSmallWonder or Smalls for short. But also, it’s believable as some of my earliest memories are of building robot kits with my mom and helping my dad package his homemade graphic cards to sell at Fry’s Electronics. All with the backdrop of Silicon Valley where I grew up.

I have no formal training or background in engineering and I’m a self taught maker who knows just enough to break things spectacularly. But I like to think that’s what’s so great about being a maker. You can pick up something to learn, experiment without preconceived restraints, and make some beautiful disasters.

I’ve learned so many things by being insatiably curious. I’ve learned 3D printing, CAD drawing, prosthetic making, sewing, water color painting, drawing, costuming, circuit design, manufacturing processes, pacific island dance, PCB creation, martial arts, cooking and so much more…

If you read this list and wonder how in the world these skills all fit together in projects… well the most important thing I’ve learned is to learn everything that interests you and you’d be surprised at how interconnected the most unexpected things are.