Solar Fractal Plant: Update

For my final project in The Nature of Code and Energy I am constructing a fractal plant, running on Arduino, that will reside on an e-paper display and be powered by the sun.

Over the last few weeks I have made progress sourcing components and getting the basic circuitry assembled following my previous post with a BOM and energy budget.

Using outputs from the Adafruit 1.5A USB/DC/Solar LiPo Charger breakout board I have setup a voltage divider circuit to read the battery voltage through one of the Arduino Nano 33 IoT analog input pins. Because the Arduino is a 3.3V board a voltage divider is necessary to drop the maximum 4v+ battery voltage below 3.3V.

My work relating to The Nature of Code will involve coding growth and variation for the plant. Like biological plants I would like the fractal plant to respond to the sun, extending its “leaves” during the day and relaxing them at night. The charge of the battery over time will impact the growth of the plant. Too little sun and the plant will be thin and leggy. Plenty of sun and it will have lots of branches and perhaps even blossom.

The style of the project will be simple line art due to the limitations of the Adafruit GFX library I am using, but there will be plenty of room for expression through colors and shapes.

One reference shared from Dan Shiffman that I hope to implement is an L-System for the fractal growth. These examples by Paul Bourke have beautiful and naturalistic variety to them and I will likely need to implement a stack data structure on the Arduino to run this kind of code.