Mermaid Glimmer is the world’s only swimmable LED mermaid tail (as far as I know). She’s my pride and joy, and probably the most difficult and troublesome thing I’ve ever made.
Creating an arduino controlled, battery operated illuminated costume that can hold up to swimming and submersing at depth was a challenge, to put it mildly, and this was really my first larger scale LED costume project. I learned so much while creating this costume.. but since she was such an early effort, there have been a number of problems with her since the beginning.
Almost every time I’ve taken her out for a performance or photo shoot she’s come home broken in one way or another. So this spring, before the gigs started up in earnest, I decided to tear her down and rebuild her, make her better, stronger, faster, and more waterproof.

The main trouble was the lights in her fluke. I used some cheap “waterproof” addressable WS8201 LED lights from China the first time through, and.. well, they really weren’t as waterproof as advertised. I pulled out about 150 oft-repaired-and-rewired lights from the tail and chucked them in the trash.

I replaced them with a newer and more robust strand of WS2812B lights, which I tested thoroughly by submersing at depth and soaking overnight in my tub, and adding extra waterproofing wherever I felt the strand might have a weak point.
I also rethought the layout of the lights. With the previous layout, any time one light would break or get waterlogged, it seemed like half of the lights on the tail would go out. The lights were in one long continuous strand, so anything “downstream” of the broken light would just lose power. For a project that’s this complicated and delicate, and meant for high-end performances at high-end events, failing gracefully is really, really important.In the new layout I have 4 individual strands in the fluke, and I put the bottom edge lights a lot sooner in the sequence since those are the most important in terms of overall look, and the bottom edge lights are doubled up as well. This means that if one light fails, less than 1/4 of the fluke will go dark, and the bottom edge will stay glowing no matter what. The remaining lights are laid out in a spiral pattern, which has done some crazy neat things to the animations I’m running and has opened up some new animation ideas and effects. I spent a bunch of time reworking the code to accommodate the new layout, and got the bluetooth controller working again. It still has a lot of room for improvements but I’m really happy with where it’s going.
For the 4th of July weekend I went up to Serene Lakes and spent a couple hours in the water, splashing around and swimming back and forth to really put Glimmer through her paces. After 2 hours of submersion, ALL the lights were still on!! (She’d been reliable for around 30 minutes, tops, with the previous layout).

I’ve got several wine club event shows at wineries in the Napa Valley booked, as well as a few apartment complex parties and private birthday party shows, and I feel like I can trust Glimmer to work consistently and reliably at all these upcoming gigs. Before the rebuild I was nervous about booking her too much, but now… bring on the bookings!!