Evil Genius Labs
Custom Electronic Art
Custom Electronic Art
Fibonacci64 Micro is a beautiful 40mm circular disc with 64 RGB LEDs surface mounted in a Fibonacci distribution. Swirling and pulsing like a miniature galaxy, it’s mesmerizing to watch.
It consists of 64 WS2812C-2020 RGB LEDs, arranged into a circular Fermat’s spiral pattern.
It has solder pads on the back that match the pinout of the QT Py by Adafruit, or XIAO by Seeed. It can be used by any microcontroller via the 5V, GND, and Data In pins. It also has a Data Out pad, for connecting more LEDs on the same data pin.
The four mounting holes are surrounded by capacitive touch compatible pads. They’re connected to the A0-A3 pads/pins on the QT Py footprint. The SAMD21 QT Py supports capacitive touch on these pins.
In disc phyllotaxis, as in the sunflower and daisy, the mesh of spirals occurs in Fibonacci numbers because divergence (angle of succession in a single spiral arrangement) approaches the golden ratio. The shape of the spirals depends on the growth of the elements generated sequentially. In mature-disc phyllotaxis, when all the elements are the same size, the shape of the spirals is that of Fermat spirals—ideally. That is because Fermat's spiral traverses equal annuli in equal turns. The full model proposed by H Vogel in 1979 is
where θ is the angle, r is the radius or distance from the center, and n is the index number of the floret and c is a constant scaling factor. The angle 137.508° is the golden angle which is approximated by ratios of Fibonacci numbers.
Fermat's spiral. (2015, October 24). In Wikipedia, The Free Encyclopedia. Retrieved 02:45, February 24, 2016, from https://en.wikipedia.org/w/index.php?title=Fermat%27s_spiral
Options available to purchase for additional amount:
If the “Fully Assembled” option is not chosen, these parts are not included, but are required to assemble and use:
Parts I used in my builds:
Open source example firmware: https://github.com/jasoncoon/fibonacci-demoreel/tree/f64-micro
Open source touch demo: https://github.com/jasoncoon/fibonacci64-touch-demo
Fibonacci boards are laid out physically in a zig-zag pattern, from center to edge and back to center, all the way around the board. This layout automatically makes one dimensional patterns designed for strips visually interesting.
To treat the board as a matrix, you can use a pixel map. A 2D XY map can allow you to scroll colors, palettes, and patterns across the panel horizontally, vertically, diagonally, etc.
This map can be copied and pasted into the Pixel Mapper in the Mapper tab of your Pixelblaze web interface.
Note: Double-check the position, alignment, and orientation of each component very carefully before soldering!
Note: Earlier versions of the PCB had header pin holes for 5V, GND, and Data In. Newer versions have pads, not holes. The pads allow you to either solder wires on, or solder a QT Py directly to the PCB.