[visualkev]’s friend was putting on his own fireworks show by lighting each one in turn, then running away. It occurred to [visualkev] that his friend wasn’t really enjoying the show himself because he was ducking for cover instead of watching the fun. Plus, it was kind of dangerous. Accordingly, he applied his hacker skills to the challenge by creating a custom fireworks sequencer.
He used a custom PCB from OSH Park with an ATMega328P controlling eight TPIC6C595 8-bit shift registers, which in turn trip the 64 relays connecting to the fireworks. A 5V regulator supplies the project from 5 5AA batteries, and he kept the wires neat with 8-wire ribbon cables.
Starting the sequence is a generic wireless remote — a cheapie from Walmart — allowing [visualkev]’s friend can launch the fireworks with one hand while working the barbecue tongs with the other.
So, uh, you need pretty specific licenses to do this kind of thing legally AFAIK.
Depends on the municipality and even country this person is located in. It says they live in Phoenix, Arizona. So if that is the case, the prevailing local laws on fireworks would apply and how they apply would depend on what type of fireworks they intend to set off. Briefly looking around, there seem to be plenty of perfectly legal fireworks that are available to be set off in that municipality with no license required to purchase or set off.
That’s a recent change. Used to be that even in libertarian Arizona all fireworks were banned from sale and use. This is due to the extreme danger of wildfires.
The laws changed in the past decade or so, but there are still county and city regulations especially for rockets or mortars.
Lol not in Texas. This state is a festering shitshow, but at least I can make myself some pretty pyrotechnics.
+10 for “festering shitshow”.
Canada’s still a free country…
I was going to put on a big musical display last Canada day, but I couldn’t get a Handel on it.
This does not sound remotely safe in the slightest :(
It sounds remotely safe (get it?) but in all seriousness, additional safeguards really should be implemented here.
I am now going to describe all future dangerous projects as “remotely safe”.
Well if you are remote ENOUGH from it, even a nuclear bomb would be safe :D
As an erstwhile Demolition Range Officer, I shuddered to think of an explosive device being triggered by radio.
Not a problem as long as it’s done properly, requiring an error-checked message and having suitable interlocks.
I agree with Mike. But this project doesn’t have those. I think there has been 1 (one!) Project I have ever seen that actually thought about how to try and do things safely.
Absolutely no mention of anything like that here…
Fireworks are triggered by radio control all the time. It is SOP for most display companies. In many jurisdictions shells over a certain size (typically larger than 6″) are required to be electronically detonated, and because of the required setbacks (typically 70 feet of setback per inch of shell) it is a lot easier to do it via radio control than running wires. Contrary to what you might think, radio controlled detonation is often times more dependable. Back when we ran a lot of wires people were constantly tripping over them and yanking the wires out or the e matches out or both. And it is not unusual for the ground to get dewy so you have long runs of wet wire. That being said, you want a remote firing system that has security. That is not just sending an idle carrier, but using some kind of a modulation scheme and some kind of a protocol that includes authentication to. There are also mandated physical aspects, such as key operated switches and dead men to prevent unauthorized and unmanned operation. The nicer units also show all kinds of useful information such as the remote battery level, remote signal strength, remote continuity on each cue etc. This seems a bit lacking in even the basic safety regards. You also need to worry about little things like when you first power the remote unit up, will any of the outputs even ever so briefly go high. That little flicker of an LED when you first turn a non critical project on is a major issue if you have that output connected to a bank of shells.
We’re all going to die in various awful ways far too soon. Go out and have some fun.
Calm down guys…. This is completely legal (in state he’s in, given that he only fires off fireworks that are legal) and it’s safer than “light and run” any day. It’s at the very least no more dangerous than standard methods of igniting fireworks. I built a similar system so my kids could trigger fireworks from a safe distance (it was wired and had two buttons so they couldn’t trigger it unless my button was pressed too) and they loved being able to participate.
I think you misunderstood their concerns. It is the wireless part that is the weak link. Accidentally unlocking your car due to spurious reception is one thing, having 64 cues go off at once is another. Especially when ones head is over the mortars or cakes. You occasionally see professional systems have an ‘oh shit’ moment.
Yeah, I wasn’t talking about the fireworks themselves, but specifically about electronic ignition and remote control. You can get yourself into big trouble with that combination.
Folks need to research a bit before exclaiming “safety!!” before you know anything about it.
Radio controlled ignition systems are more popular every year. Only a small part of it is the cool factor. It’s widely accepted among pyrotech hobbyist and pro alike that remote ignition is safer by far than manual fuse lighting. That’s universal and easy to find out if you look into it for five minutes. And radio control ignition can be the safest because you can position yourself even further away with less difficulty.
By the way, I’ve seen several dozen home-made ignition systems which work well and are safe, and the one featured here is a particularly well-executed example.
You could be safer by staying inside and watching TV, or you can get out, take a chance and enjoy some actual experience.
You could stay in your house…. but avoid the bathroom, stairs and kitchen, that’s where you’re statistically most likely to die.
I’m just talking about the legality of such systems, nothing else. Of course it’s safer if done right.
+1
The wireless link, can lull you into a false sense of security.
I can’t see any specs on the wireless remote control that was used, but I’ve used a wireless door bell for several years and it occasionally gets miss triggered by interference.
One of the door bells I had, played a different sound depending on a switch setting in the bell push its self, and occasionally my bell receiver would ring, but play a different tune.
Hence this is not simply someone ringing the door bell and running off before I can get to the door.
This didn’t happen that often, so I presumed it was not simply someone else in the neighbourhood with the same model door bell.
Statistically the chance of a miss fire are probably very very low, but the result of a miss wire could be deadly.
So you’re saying it might not be the most reliable?
https://i.makeagif.com/media/5-12-2015/AkupyQ.gif
Whenever you have something that can kill/seriously harm someone, “not the most reliable” is something you do not want to see on a spec sheet :P
Seems like a lot of unnecessary work.
He could have just bought a $12 STM32F103VET board from AliExpress
e.g.
https://www.aliexpress.com/item/FREE-SHIPPING-ARM-Cortex-M3-mini-stm32-stm32F103VEt6-Cortex-development-board-72MHz-512KFlash-64KRAM/1378852993.html
The directly connected his external relay boards.