Neopixel Hat

Project Overview

Originally created for Halloween, this project evolved into a display piece for offseason First Robotics competitions. It uses an Arduino with one strip of 576 NeoPixel LEDs to create a cylindrical display on a top-hat, capable of showing various animations.

Technical Implementation

1. Hardware: Arduino controlling a strip of 576 NeoPixel LEDs
2. Animation Storage: Animations are stored as 8-bit and 32-bit arrays
3. Compression Algorithm:

   • Created a Python program to import sets of images
   • Compresses images by grouping sets of pixels together based on their color
   • Stores group-size and color-id information in one large unsigned integer array
   • Color palette of the animation stored in another 32-bit integer array
4. Memory Management: Animations stored in Arduino's PROGMEM (flash storage) to maximize the number of animations that could be stored at once

Animation Workflow

To create complex animations efficiently:

1. Used Blender to render out 2D animations
2. Processed these animations using the custom Python script
3. Imported the processed data into the Arduino program

Results

This solution allowed for dozens of animations to be stored on the hat at a time, a significant improvement over the previous method which only allowed for about one animation (approximately 50 frames) at a time.

Future Improvements

• Implement wireless control to change animations on the fly
• Develop a mobile app for creating and uploading new animations
• Explore more efficient compression algorithms for even more animation storage