Neopixel Longboard

Hackentosher · October 1, 2018

Hey guys, I know I'm not too active on the forums anymore, but I figured people here could appreciate my latest project. So I currently attend one of the largest (geographically and study body) universities in the United States. Getting around can kinda suck sometimes, so I bought a long board. Instantly, I knew I had to pimp it. The lab I work at had some spair Ws2812b leds, and said I could have one. A little bit of The ol jazz hands routine, and waiting à week for an adafruit order, here we are.

I added an adafruit feather NRF52 board to control the leds, and a 1s2p battery from 18650s I had lying around. The best part? It's frackin Bluetooth

Now just as every diy project, it's not perfect. The feather has a built in charging circuit, but it is not meant for really big bateries. Iirc, it charges the battery at like 100ma... The battery I built is 4000mah. So if the battery is completely dead, it will take a theoretical 40 hours to cometely recharge. Next up, the led at the very end of the strip often flickers different colors and doesnt function properly. Not sure why, I'll probably have to cut it off. You also may have noticed the electronics box isn't very clean, it's currently held together with duct tape.

Now, the big problem (and let's be honest, one of the reasons I'm posting about this) is the NRF52 feather I bought is not compatible with the FastLED library. This really sucks because FastLED is, imo, way easier to use than the neopixel library, and has better documentation. FastLED has HSV control, which assigns color control to an 8 bit integer. This makes rainbow animations way easier because you can just add 1 to your color variable and it'll cycle through a rainbow as the arduino loops the code.

Anyway, if you'd like to help me write animations for Neopixel, please feel free to drop some knowledge, advice, feelings, or ancient scrolls below. I was able to write a few animations in FastLED that is like to recreate such as

Rainbow fade (fade through the rainbow)
Rainbow chase (chase a rainbow around the perimeter of the board)
Rainbow breathe (gradually brighten on one color, fade back down to zero, repeat on a new color)

The NRF52 Feather is Bluetooth enabled afterall, and there's an example sketch called Firmata that let's you control the state of pins on the board over Bluetooth through the adafruit app. Sooo the end goal is to be able to select the animations using the pin state thing on my phone.

Anyway, this post kinda ran away from me in length, but I wanted to show off what I've been up to.

iamdarkyoshi · October 2, 2018

5 hours ago, Hackentosher said:

the led at the very end of the strip often flickers different colors and doesnt function properly

Try putting a capacitor across the 5v/ground rails on the end of the run, betting the voltage rail is getting noisy

Hackentosher · October 2, 2018

5 minutes ago, iamdarkyoshi said:

Try putting a capacitor across the 5v/ground rails on the end of the run, betting the voltage rail is getting noisy

maybe, but it was working fine until i had to chop off an LED at the beginning of the strip when a pad ripped off. Idk, it's just one LED, I'll be okay with chopping another LED off as it's a very dense strip. 144 LED/Meter, that I got for free from my job