Shooting Stars
This is an all-DIY project that gives you a chance to use your 3D printer to create a nifty lighting effect! It's not a hard project, but it's a bit of a time-consuming one depending on how many "stars" you incorporate into your display. For this project, the author designed a 24-star line with stars approximately 1 foot apart. The goal was to create a display piece that could be wired from the ground up to a larger main star mounted in a tree or on a garage roof so that it would appear like an eye-catching "swoosh" of light rising up to the main star. Therefore, each star in the line needed to have individual control.
It was thought that while a string of pixels could certainly be used to accomplish the animation function, the individual pixel bulbs weren't large enough to be truly eye-catching. But pixel technology could certainly be used -- just not with individual bulbs. And since color wasn't important, a project similar to the monopixel candy canes (highlighted HERE) seemed appropriate.
First, a star had to be made. This proved to be quite easy on Tinker Cad, which provides a basic star shape. It was enlarged to approximately 4" across nd the center raised. Then it was duplicated on the screen, the duplicate was reduced in size by about 2mm in all directions, set to be a "hole" and simply merged into the first star. This resulted in a star "half-shell" that when two stars were glued together, would provide plenty of room for electronics inside. For the 24-star display, 48 were required. (Note: printing time was a bit over an hour each which is why this project takes some time... The STL file for this star is at the end of this how-to.)
The electronics inside the stars were simple: five white LEDs soldered onto a two-sided piece of spare PCB stock. Anodes soldered to one side; cathodes to the other and a lead wire soldered to each side -- all 5 leds would be in parallel. The wire chosen was a pair of wires stripped from a length of CAT5, chosen for low-cost, it is easily able to handle the tiny current needed to illuminate the leds but it's also not very visible.
The LED components would be connected to an inexpensive WS2811 board designed for square-base pixels using the board's RGB and +V connections. A prototype of 3 stars was made and tested for feasibility before investing more time in the project. A video of the prototype is here:
more to come----