RGB Tea Light Candles

These are a set of three rainbow tea light candles I made for a four-hour hackathon at my college. They are powered from a rechargeable LiPo battery and each run off an ESP32 programmed with the Arduino IDE.

The lights themselves are Neopixel LEDs, which are individually addressable. This allows for a wider range of expressiveness through combinations of hues.

The RGB Tea Light Candles

I wanted to explore what kind of experience could be created if you gave tea light candles the ability to talk to each other. My plan was to implement a system so they could communicate over ESP-NOW, the wireless ESP32 peer-to-peer protocol. They could sync their internal states with each other and each become a single node in a larger meta-animation that would play across an entire room. Unfortunately, I only had enough time in the four hours to finish the hardware, and did not get to the software. I plan on finishing the software at a later date.

The inner acrylic frame.

The hardware is designed around an acrylic frame that neatly holds all of the electronics in place. The frame is the perfect size to fit inside a piece of PCV pipe with an inner diameter of 40mm. The pipe slides over the frame and makes a pretty good improvised enclosure.

The LiPo charging module

I created the design in Fusion 360, then exported the flat faces as vector files to be cut out on Hackberry’s laser cutter. The acrylic peices were put together inside a PVC pipe to ensure proper alignment, and then were secured with CA glue. Spray accelerator was used to instantly harden the glue so I could handle the frames without wasting time.

Most of the soldering was meticulously done with the components inside of the frame. A lot of care had to be taken not to bump the soldering iron into the enclosure or overheat the battery. I probably could have gotten away with not doing this, but I am happy with how clean I was able to get the wiring this way.

They are USB-C chargeable!

The RGB Tea Light Candles won Judge’s Choice at Hackberry’s October 2024 Hackathon!