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Posted by: KamuiK 6 Aug 2009, 17:33

This thread has been presented and created by seperating it from the other thread by yours truly:

THE_HUNTER

No KamuiK's have taken damage while doing so.

My opinion:
There should be no recoil animation - Railguns have no recoil (ok, they also have no sound, no muzzle flash, no muzzle smoke amongst other things, so your decision^^).

Posted by: Rade 6 Aug 2009, 18:10

What makes you think that the rail guns don't have a recoil.

Posted by: The_Hunter 6 Aug 2009, 18:27

what your refferng to is a Laser Kamiuk not a Railgun which is very different from a laser.

Posted by: BlitzGeneral 6 Aug 2009, 19:03

Railguns strike me more as ECA thing anyway. :/

Posted by: KamuiK 6 Aug 2009, 19:20

A Laser has no recoil and other tings either, but a railgun cannot have a recoil, since it shots a bullet via electricity instead of a chemical reaction. I know how railguns and also gaussguns work, trust me.

Posted by: Dutchygamer 6 Aug 2009, 19:23

I do think there is recoil, else the projectile wouldn't fire. Action-reaction right? Even though with railguns it's more that the barrel would bend instead of recoiling, but that is a different subject...

Posted by: Alias 6 Aug 2009, 19:24

A railgun has to have recoil as it is a projectile weapon (rails being the operative word here, the projectile makes contact with the 'rails', I think what you're thinking of is a coilgun). It is basic physics that it must exert the same force backwards on the barrel that it exerts on the projectile itself.

Posted by: Anubis 6 Aug 2009, 20:01

As far as i know railguns do not have a recoil. According to the same physics law, the recoil force is equal with the force that pushes the projectile out ( action/reaction ). If this was the case, the recoil would be huge for a projectile that travels at over 20000 km/h . Railguns use electrcity to launch the projectile not explosives. Electricity is a one way force ( an electron wave ) not a 2 ways force ( such as an explosion ). The only viable railgun i/ve seen so far is the one in Transfromers 2. It had no recoil, and the projectile was launched via a complex railsystem. So i'm with kamuik on this. Railguns do not have a recoil, or else the whole damn turret would fly off from it's support ( crazy mod abrams style ).

Posted by: KamuiK 6 Aug 2009, 20:07

Quoted for correct explanation.

Posted by: Comr4de 6 Aug 2009, 21:31

Now you can say you've seen a real one instead of basing it off what you've read or seen in movies. Obviously the creation and execution of a railgun is not set in stone but what I can tell you is this:

Railguns were given to the Russians since to me they're blunt weapons thrown out of a cannon faster than you can say 'Oh SHI-'. Russian Railguns are nothing more than a metalic rod shot out of magnetic railings (you can assume there's some tesla tech in them as well to correlate the theme) and are thrown to targets by pure kinetic energy. No explosive inside it it just whatever was getting hit by it just went kaboom due to the huge penetrated hole it created. It wont have of the shitty effects CnC has done for railguns with fairy like waves or lines coming from it -- no, just a bang and a frame of a metal rod going up your tanks bum hole

Posted by: tempestora 6 Aug 2009, 21:56

Hey everyone, long time lurker (shockwave0.92 i think), obviously new poster, needed to correct some misinformation and misunderstanding here about the laws of physics pertaining to magnetically accelerated weapon systems.

Sorry guys, but thats not how railguns/coilguns work, in fact, thats not how the universe works.

why do i know this? High School Physics

Why do I know this in great depth? 3rd Year BSc in Nanotechnology at UNSW and general geekiness (kinematics is extensively covered in PHYS1131)

And with a simple explanation of Newtons laws of motion, I'll demonstrate why you are wrong, but first some clarifications and definitions.

Rail Gun: a set of electrified conducting parallel rails (which means a strong magnetic field surrounding the rails) which form an incomplete circuit, and a projectile which is placed at one end (suspended between the two rails in a manner that allows it to move freely along the rails) which completes the circuit, allowing a large current to pass across and as such that it interacts significantly with the surrounding magnetic fields (Electromotive Force) and hence accelerating under the lorentz force (right hand rule people! year 11 physics!)

Coil Gun: a series of electromagnetic coils arranged in a linear manner, which are precisely controlled to turn on and off so as to pull/push a ferromagnetic projectile through and accelerate it.

In both sets, electromagnetism (either the lorentz force which is the force acting on a conducting material in a magnetic field & uses the same effect, but in a different manner) is used to accelerate the projectile, the huge speeds they can reach is due to the magnitude of amperes that can passed along those systems. Thats why they use lighter ammunition, since KE=m(v^2), and that juicy squared velocity term means that you can more easily and cheapely increase the kinetic energy of impact of the projectile by increasing its speed rather than mass. But that kinetic energy term (which pops out of F=ma when you differentiate) also applies to the rails or coils in the respective weapons. Its the same force, applied backwards, but over a much larger mass, and hence much lower velocity. when you accelerate something forward, you are also accelerating something backwards (thats how rockets work, its the same law governing it, F=ma, and why they would rather use very light fuels like hydrogen to accelerate, because they have a better velocity term. bad explanation, i'll edit it after i get some sleep).

There is still recoil in this system, since just because you are using a different type of fundamental force, namely pressure from the expansion of a gas, and electromagnetism *actually not really, both are electromagnetic, i'll let you wonder why* to impart kinetic energy to something, doesnt mean there is a seperate set of laws governing the acceleration of objects. its all newtonian in nature my friends. Your transformers movie got it wrong.

thus concludes my insomnia inspired explanation.

this would have all been the more easy if i had thought to post a link to wiki, but i'll be damned if i delete all that work.
some reading if you are interested:
http://en.wikipedia.org/wiki/Railgun
http://en.wikipedia.org/wiki/Coilgun
http://www.youtube.com/watch?v=i1q_rRicAwI cool firing video
http://science.howstuffworks.com/rail-gun1.htm

please feel free to correct any mistakes, i blame it on the 5 bottles of wine and lack of sleep

Posted by: Destiny 6 Aug 2009, 22:14

Pardon me for being blunt but...

"This is a game." I know it might be a game and making it semi-realistic looks cool and such but...

Posted by: Comr4de 6 Aug 2009, 22:18

Welcome to the forums tempestora, you know your stuff man, and it is exactly how'd we make our railguns to be.

Doesn't mean we can't just make Railguns awesome from what you can gather in this information. Do I have to say it?

Simple metallic rod + Railgun + force + tank target = big ass hole on the side with explosion from internal damage (big bang).

Posted by: Destiny 6 Aug 2009, 22:35

Perfectly worded there

Edit: ...ahaha~

Posted by: KamuiK 6 Aug 2009, 22:48

It was not his critique to use them at all, it was his critique about what Anubis and I said about Railguns. About having no recoil. Also, I know how a Gaussgun works as well, and I say it now just as on other locations: I will not start a flame war. As long as someone shows me a Railgun with recoil, I will stay on the opinion that my last Railgun had no recoil.

Also, question: any idea on remodeling/improving the russian Command Bunker?

Posted by: Nidmeister 6 Aug 2009, 22:52

This my friends, is how a first post should be.

Posted by: Raven 6 Aug 2009, 22:56

Well i would mean more or less like the LOSAT humvee isn't it? It also uses kinetic projectiles

Posted by: tempestora 6 Aug 2009, 22:59

Haha sorry, i wasnt asking the railguns to be like that, i just saw someone posting information that didnt match up to reality as im aware of it being and was hoping to demonstrate that there is a more accurate scientific model available.

No requests from me, its purely posted to hopefully convince KumuiK and Anubis that there version of kinematics doesnt sync with the general consensus.

i had an xkcd moment http://xkcd.com/386/ what can i say.

Actually most of the damage from the rod would be from spalling, plus, at a high enough velocity (in atmosphere) it will have started to melt. And liquid hot iron doesnt do wonders to your fragile meatbags driving the tank, at 0m/s or 3000m/s

hmm next thing to figure out, air friction at 3000m/s of a cylinder vs melting point of conductive alloys...

@Raven:
Similiar in terms of how they do damage, no explosive warheads, just absurd kinetic energies involved. The method of propelling the projectile is different though.

@Nidmeister
Thank you very much, I hope I can be as some asset to the community in terms of discourse

@KamuiK
im sorry that i cant physically demonstrate it to you, but its a matter of doing a force diagram. check out the published answer from the Department of Energy answer, it will clear things up more concisely than i did. http://www.newton.dep.anl.gov/newton/askasci/1993/physics/PHY24.HTM

EDIT: cheers, sorry for derailing the thread.

Posted by: The_Hunter 6 Aug 2009, 23:14

Since this is a interesting topic but was beeing posted in the wrong place i'v token the liberty of seperating it from the original thread disscus away

Posted by: KamuiK 7 Aug 2009, 0:19

Can someone please lock this piece of sh!t? Thank you. I did not start this topic, so remove that thing.

Edit: scratch that.

Posted by: Shock 7 Aug 2009, 0:30

I am very interested in your explanation on how a chemical explosion is actually also elektromagnetic force.

Cheers! Now we finally know why EA's laser tanks have recoil!

Posted by: Overdose 7 Aug 2009, 0:42

I doubt somehow EA researched that much.

Posted by: tempestora 7 Aug 2009, 2:09

@Shock

ahh well, exothermic chemical energy (an explosion is a exceedingly rapid exothermic reaction) is energy released in the formation of bonds (its not stored in the bonds! common mistake, its released in the formation of bonds as it goes down a thermodynamically favourable path. instability ->stability). Electrons are bonding covalently or ionically, and that happens through electrostatic forces (see where im going with this yet?). The actual enegy exchange is done by virtual particle interactions (photons for the curious) which is only on the peripherial of importance for my field, so i dont know much about that. Ask a particle physicist

Photons are electromagnetic energy packets, so at the very fundamental level, yep its all electromagnetic. But there is also the fact that when something collides with another, its the electrostatic repulsion that stops it passing right on through, again mediated by virtual photon interactions, which is how you get pressure

If i actually understood it properly, id go into how everything that we understand is ultimately modelled accurately by the electroweak theory, a combination of the electromagnetic forces and the weak nuclear forces into one force that breaks at low energies we experience.

but thats not my field, i have enough brain ache from my other courses to have my mind leak out my ears from the bizarre nature of quantum physics.

I can go into more depth if you like, but im starting to press the bounds of simple explanation and starting to need to go into some awful maths to make sense of it all.


@Overdose
Im sure that EA, with its focus on well thought out, realistic game physics, worried about accurately modelling photon momentum transfer. Id expect nothing else of a giant of the industry

Posted by: ultimentra 7 Aug 2009, 5:11

Sorry for deviating from the topic at hand, but what are the main differences between Railguns, Gauss Guns, and Coil Guns?

Posted by: Viper 7 Aug 2009, 6:37

IIRC, a railgun is a weapon that uses like charges on the projectile and rails (used to guide it) so that the projectile is forced away.

in a coilgun, the charges in the weapon switch from + to - really fast, thus moving the projectile.

as for a gauss gun, i have no idea

Posted by: Destiny 7 Aug 2009, 11:51

Some pics from wiki to help facilitate imagination.

Railgun:


Coilgun:


Gauss Gun = Coilgun

Posted by: Shock 7 Aug 2009, 12:13

Well you see on the old Fallout Studios, as you probably know, there is Dauth who is an MPhys and usually jumped on to things like this just like you did, though he kept his elaboration to a bare minimum.

Don't go into math's though please, the fact that it all boils down to particle physics scares me away already.

Posted by: Drag#! 7 Aug 2009, 14:36

Whats the point of this thread at all...

Posted by: Shock 7 Aug 2009, 15:02

Posts like that make me wonder why some people visit forums.

Posted by: Drag#! 7 Aug 2009, 15:05

Fine, if u want i wont visit this forum then

Posted by: ka1000 7 Aug 2009, 15:17

not exactly, a gauss gun works by this principe

Posted by: Nidmeister 7 Aug 2009, 20:06

Well correct me if I'm wrong, but I assumed it was to discuss how railguns work.
I would have thought that was fairly obvious?

As far as development goes though, I dont think any scientific facts are going to change the way railguns work in game though.

Posted by: Nem 7 Aug 2009, 20:52

Leave, Nobody wants your unprovoked negativity.



This is true to a certain extent, They should and probably will be based on loose scientific fact though I imagine "Whats cool" will play a much larger role in dictating how the railgun looks and feels.

Posted by: Shock 7 Aug 2009, 20:59

Yeah please depart, you failed.

As for railguns in game. Well iirc they are fast projectile weapons that can move right through their targets, a bit like a railgun in real life should work too, provided the ammunition can do it (see tempestora's concern about melting projectiles).

Posted by: Nidmeister 7 Aug 2009, 23:16

Exactly, and recoil is cool

Posted by: Destiny 8 Aug 2009, 6:48

I wonder if it's possible to have the railgun shoot through multiple targets in-game...though it really wouldn't make sense with all that ERA they're putting on tanks I agree that the "Coolness" factor is more important that reality.

Posted by: tempestora 8 Aug 2009, 7:33

@Shock
If you are interested, i can do the calculations for the frictional heating of the projectile once i find my aerodynamics textbook. Not going to bother if no one cares though, since thats effort

@Destiny
ERA wouldnt be an effective countermeasure versus a purely kinetic weapon system like a railgun accelerated projectile (the reason behind making the Kinetic Energy Penetrator projects that the US military keeps funding, LOSAT is one of those, is in fact to defeat ERA equipped armoured vehicles)


Personally, i prefer the game to be cool than realistic, it would be neat to see the hit animation sfx to include the effects of spallation (big cone of material being ejected out the otherside of the object as the projectile passes through) instead of a generic explosion (which would make no sense, its lacks a warhead). But thats just neat eyecandy, and no point doing it if its going to be more difficult than its worth.

Posted by: Shock 8 Aug 2009, 13:14

Well SAGE has many things like that which don't make sense. For example a driving technical being hit by something like toxins will also fly up in the air in a nice explosion

Posted by: Failure 8 Aug 2009, 22:01

Can I make the effects.

It can be done.
The big cone of material, can be done by spawning small particles with specific textures like metal shrapnel or bigger parts, and just orient the emitter to object in fx_list. Also damnload of white/blue electric sparks and we're rollin

When I'd get back to my rig, and get permission for doing this

Posted by: ultimentra 9 Aug 2009, 10:14

Thanks for answering my question destiny and ka1000. I personally think the team should do whatever they feel is best, and we should accept their hard work. They aren't getting paid for this you know.

Posted by: tempestora 10 Aug 2009, 23:58

failure, you do not live up to your name
that sounds epic, look forward to seeing it if it happens.
for those who dont know what spallation is, handy wiki link for you. http://en.wikipedia.org/wiki/Spalling

Posted by: Failure 12 Aug 2009, 2:03

*When I'd get back onto my rig


Also I don't know if it will be used anyway since I had that request but a while ago and I don't know if someone made it already.
But it will happen and I will paste video link here if it's allright.