In this project we’ll show you how to build a POV LED wand. Adafruit DotStar’s deliver high speed PWM making them great for Persistence Of Vision. It’s powered by Adafruit’s Circuit Python, making it really easy to change and modify. The Adafruit Feather shows up as a USB drive so you can drag and drop the code. The handle and wand were designed to be 3D printed and houses all of the electronics.
As the LEDs move in space, they flash different parts of an image, building up an image in your brain. Using a long (several seconds) camera exposure, a single row of LEDs under computer control displays an image one line at a time while it's carried or rolled across the frame. The combined result is a luminous picture floating in air.
The software running this build was written in Circuit Python. This means there's no "post-processing" for the images making it super easy to drag-n-drop new images onto the CIRCUITPY USB Drive! All of the image processing is done on the fly, straight off the flash chip.
The design is reminiscent to a wand, so it's meant to be held in hand. It's fun to wave this thing around. The Feather and battery are housed in the handle and secured with machine screws. The handle is split in two halves that snap fit together. The LED strip is tapped to a stick thats designed to be clamped to the handled. An on/off switch is fitted inside the handle and easy to access.
There's certainly no shortage of POV projects on the Adafruit Learning System (Just search for POV). From talented makers like Limor Fried, Erin St. Blane, Becky Stern and Phillip Burgess, these are by far the most impressive. This POV build, however, uses the Adafruit Feather platform – You get built-in USB battery recharging, prototyping area, and extra power and ground pins which results in a build with less parts. The Adafruit Feather form-factor is perfect for this sort of thing!
Here's a list of some of the POV projects on the Adafruit learn system. Each uniquely designed and developed with different platforms, components and software. Each one is special in their own right!
If your new to electronics and the Adafruit Feather M0 Express, I suggest you walk through the following guides to get the basics. The Adafruit Feather M0 Express guide will walk you through setting it up with CircuitPython. See the DotStar guide for more information on how they work.
You'll need just a couple a parts to build this project. The DotStar LED strip comes in a meter long with 144 pixels. The 2200mAh lipo battery connects directly to the Adafruit Feather. A slide switch will power the circuit on and off. The Adafruit Feather M0 Express has built-in USB recharging.
These things really do help make building the project smoothly. You don't need them all of them, but I recommend them.
This is a nice tool for creating light paintings. I'm surprised how much detail can fit in 32 pixel tall graphics, text, shapes and patterns. Images with a lot of color really show just how vibrant the DotStar LEDs can be. Rainbows and other multi-colored patterns look amazing!