Electronics design and fabrication help needed!

CadillacBob

New Member
Just started a 1:1 replica of the Machine Gun Joe truck from Death Race. Were getting through the mechanical's and starting to build the armor which I have covered, but I need some fabrication help in particular for the weapons simulator. The truck has 6 forward firing guns, 4 1919 Brownings and 2 Vulcan gatling guns. My intention is to make the guns look and sound as realistic as possible.

The Vulcans will use 12 volt motors to spin them up, and all 6 guns will be equipped with LED nitrous purge units on the tips. When activated, an on board C02 tank spraying a burst through the illuminated purge valves will create a simulated muzzle flash from each gun. A substantial audio system within the truck (multiple subwoofers and horns for some scary loud ground-pounding noise) will simultaneously play pre-recorded heavy weapons audio that when combined with the illuminated spray from the tips, will create the sound and appearance of the guns actually firing.

And that's where an electronic controller comes in.. ultimately I need a device that functions off of 12VDC that when activated by a momentary switch (such as a trigger on a steering wheel), will provide instant-on audio output (mp3 or any other format) of a recorded auto file (heavy machine gun fire) from either a RCA or headphone style jack to the audio system, and will also provide a rapidly pulsed 12VDC output to power the purge valves and illuminators on and off. Ideally we are looking for about 5 bursts per second, but something that could be adjusted for faster or slower bursts (maybe as slow as 3 and as fast as 10) would be ideal. Ultimately it needs to be able to hold up to the NVH of an automotive application. I do not imagine this is a very complex item to build, but I have sooo much time to invest in the fabrication of the truck, its armor and weapons that being able to outsource the weapon controller would be a major help.

I would love to hear from anyone who might be willing or able to help... thanks!
 
I have recently discovered the wonders of Arduino. The key here is the Arduino would need to run relays to each item. Automotive relays maxing out at about 80 mA shouldn't be an issue. You could do this manually but it's a lot of relays and wiring that the arduino can replace.
 
IMHO.. there are still a lot of variables that need to be know to give the best advice.

1.) What LEDS are you planning on using in the muzzle?

2.) More about these LED nitrous purge units on the tips/CO2 tanks you want to use? (full specs?.. link to datasheets?)

I sorta did some thing similar (effects wise at least.. not as many guns..lol).. for a DC-17 build:


there are some pieces you wouldnt need like the bar graph and counters.....but the rapid fire (and single fire as well... along with grenade) sound FX and led lighting..etc

the audio is decent.. but not 'ground thumping' as you want... maybe using externally powered/amplified speakers would help though?


Is the 12v coming from the car battery then?

Arduino's are +5v based boards... so powering or controlling 12V devices.. will need some transistors/mosfets..etc
 
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Here is what a LED nitrous purge looks like when firing:

https://youtu.be/r8oTGzo03x4

Here is a link to the purge light assembly:
https://www.holley.com/products/nitrous/nitrous_components_and_accessories/purge_kits/parts/16033NOS

Essentially I would be using one gas solenoid at the bed-mounted C02 tank to control gas flow which would then be plumbed to 6 individual LED tips on each of the guns. So ultimately were talking 30 LED's and 1 12v solenoid would be the total load.

The audio will be externally powered (multiple Rockford Fosgate speakers, subwoofers and amps) so all I need is a audio source signal, no speakers or amplification.

Yes, the 12v will be sourced from the vehicle battery.
 
the gun kit was made from wood, and not mine.. it was made a by a guy named Woodchuck (might be a member here?)


Lets re-cap to get some solid numbers.


1.) how many 'total' guns?
2.) how many leds per gun?
3.) each gun needs to the CO2 purge..yes? so its really not just 1 x 12v solenoid.. need a way to trigger it to each individual gun barrel...no? (you'll need several of the elbow joints and tubing...etc.) (and probably a transistor/mosfet for each gun you want to have CO2 coming from)

or is each gun going to have one of these 'kits' on it?

are you using the led module in the link/kit as well? if not.... what ones?
 
6 guns total (4 brownings on the hood, 2 vulcans on the bed)
Each tip has 5 LED's, so 5x6 = 30 LEDs total
Yes each gun needs to purge, but rather than running 6 valves, I am only going to run 1 valve at the tank. I intend for all guns to fire simultaneously when demoing the truck so I didnt see any reason to add the cost and complexity of multiple valves.
Yes, I plan on using the purge tips as shown in the kit, 6 tips and 1 valve.

Interesting enough, I did find a pre-existing solutions for my pulsed 12v requirement. Looks like a company called ZEX already makes a unit to give that "machine gun" style purge:

http://news.compperformance.com/Instructions/ZEX151.pdf

https://www.youtube.com/watch?v=gVcm8Bc6JQ8

So that will take care of that component... now I just need a solution for my instant-on audio source and I am good to go.
 
* Having all guns fire at same time will easy the difficulty of this project. (will this be enough 'power/juice' to get up to and out of all 6 valves/nozzles from just the one bottle?)
* Still needs some specs on the leds (forward voltage? mA needed?) if they are just basic accent leds.. they probably run about +3.1-+3.4v and maybe 30mA max? (but thats up to you find out) :)




Update: if all you need is audio (not sure what you mean by instant on)* .. then you should be able to get some sort of audio player or mp3 player and trigger the sounds..

probably tapping into the purge kit you linked to above, that you are going with? so it can trigger the audio playback each time it 'pulses'...
 
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