One good reason to build a reliable MCU fireworks launcher is safety. Every year at least a few people get hurt when they light fireworks, sometimes losing a finger or suffering even worse injuries. MCUs can be used to build complex fireworks launchers, but even a simple launcher that safely lights off one firework at a time would be worth building. A simple electronic launcher for fireworks doesn't need an MCU to be safe and effective, but it makes it more fun and interesting to build.
If you want to build a slightly complex launcher, my recommendation is that you first look at the SparkFun "Firework Igniter" project. If that isn't quite what you're looking for, two more possibilities to check out are the "Microcontroller Launcher" by Adam Melton, which was featured on Hackaday, and the "DIY wireless firework control" at tuckie.net. For someone not satisfied with those three choices of MCU projects, the next step would probably be to spend time on the pyrotechnic forums. You'd likely be able to connect with someone who knows of one or more people who have built their own fireworks launchers.
|SparkFun Firework Igniter|
|Adam Melton Launcher|
If you absolutely know you want a more visually impressive system than the SparkFun one, the 16 station unit like Adam Melton's project might be a good choice. He found a case that worked for his design by going with a Plano waterproof case from Academy Sports. The case and electronics for the DIY wireless fire control system at tuckie.net is even more elaborate -- see the picture to the left below. My overall point is that when you're figuring out how much time and money you'll spend building your launcher, make sure you take into account the case you'll need for the electronics you put together.
Although a fairly simple fireworks launcher might be your first 4th of July MCU project, as the Internet of Things drives the production of MCUs up and the cost of them down, there will no doubt be some spectacular and interesting fireworks displays that use MCUs to create new and impressive visual effects. The BetaNews article about a Chinese artist embedding microchips in 'smart fireworks' shows one new use for MCUs in fireworks. According to the article,
|MCU Fireworks by Cai Guo-Qiang|
"At the Arab Museum of Modern Art in Doha, Qatar this week, Chinese artist Cai Guo-Qiang put on his largest "explosion event" of the last three years, utilizing microchip-controlled explosives to form incredible designs and patterns. The video we've embedded of the event is an impressive testament to how a volatile black powder explosion can be controlled and shaped by computer. Each set of explosions was calculated to paint a different picture. One series of explosions created black smoke clouds that looked like "drops of ink splattered across the sky." In another, 8,300 shells embedded with computer microchips exploded in a pyramid shape over the desert...In 2001, Cai began developing a technique to use microcontrollers to more accurately time his explosions. Fireworks are typically ignited by a fuse, and the delay of the explosion is simply determined by the length of that fuse. However, this is an extremely imprecise science due to the variation in fuses and construction of fireworks."The video in the BetaNews article is worth watching to see how the MCUs are used.
I hope your 4th of July was safe and enjoyable!