Tank Fire Control Systems

[Scrub 0]

I think it's just the disparity from this 'Manly' tough wargame and it's deadly new features, to the 'snuggle and bunny kisses' that's the funny part..

[NonWonderDog 0]

I've pretty much isolated the AI problems, but I don't know how to fix all of them. The optics code isn't the problem, because it only runs on the player (or the gunner of a player commanded tank if you switched to the gunner's position and then switched back -- I've fixed that now).

The first problem was due to T-72s loading HEF rounds by default. This was a bad idea, because the AI doesn't know when to switch ammo types. I don't actually know why they always aim over your head when firing HEF (they expect there to be more drag on the shell than there is?), but they don't do it when firing APFSDS. They can routinely hit me out to their (still rather short) maximum engagement range if both tanks are stationary.

The second problem is, I believe, due to the slower turret traverse rates. I'm not sure exactly what's happening, but I think the AI is getting confused whenever its ability to track a target is limited by maximum traverse rate. I think this is what causes the gun to get locked at maximum elevation and rounds to detonate under the tank. I'm not sure what to do about this, because I really don't want T-72s to spin their turrets around in 5.2 seconds like before. I haven't had this happen in a player commanded tank, so I'm still holding out hope.

The FCS modes toggle between ammo definitions; it tells the FCS which ammo lookup table to find the time-of-flight and drop data on. At ranges under 800m you might be able to get a hit with the wrong ammo type (because MPAT rounds are surprisingly close to APFSDS in trajectory), but at long ranges you won't even come close. To do it the right way, select APFSDS mode whenever you load M829A2, and select MPAT or MPAT (proximity) mode whenever you load M830A1. Proximity detonation isn't selected this way in real life, but I've cluttered up the action menu enough.

The gunner has to manually select ammo definitions in a real M1A1, but the T-72 autoloader should actually take care of this when you reload. You just need to turn the dial to the ammo type you want and push the big "LOAD" button (I've never actually seen a picture of the autoloader controls in a T-72, but this is the general idea). I don't think there's anything I can do to make that happen.

Most new tanks actually have the shell type magnetically encoded on the casing, so you don't have to fiddle around on the gunner's panel. I won't be able to script that in if someone makes a Challenger II or a Merkava, but that's how it's supposed to work.

[Kizzma 0]

Hello, I'm kind of new with ArmA and I've been having a bit of trouble:

I downloaded this, unpacked it, and put it in the same directory as the game's executable file as seen here.

I also put the command line in the shortcut' properties like so.

I do have the event handler thing extracted and put into what I think is the correct folder, so I don't believe that that is causing a problem. "C:\Program Files\Bohemia Interactive\VBS2\ca\addons"

Now when I try to load the game up, I go into an M1A1 as a gunner, but I don't have the updated firing scope and it looks like this.

Is this because I'm running VBS2?  I've been trying to figure out a way to get this working, but so far I havn't been able to.  If anyone could help me out it would be greatly appreciated.

[Canalien 0]

Alright, thanks... so really is there much difference between the MPAT and HEAT FCS options considering it's using the same shell?

Any ideas on the auto-reload problem?

[Scrub 0]

Quote[/b] ]"C:\Program Files\Bohemia Interactive\VBS2\ca\addons"

You have VBS2? This is for ArmA, specifically. Not sure of the differences in engines.

[Maddmatt 1]

...

And inside the @NWD... folder you have another seprate addons folder? Maybe since you run VBS2 it's "ca/addons"

[NonWonderDog 0]

Alright, thanks... so really is there much difference between the MPAT and HEAT FCS options considering it's using the same shell?

Any ideas on the auto-reload problem?

They aren't the same shell.

HEAT mode is for M830-MP-T, with a muzzle velocity of 1140 m/s. These aren't in the standard loadout.

MPAT mode is for M830A1-MP-T, with a muzzle velocity of 1410 m/s.

The Army has this thing about calling every APFSDS shell M829Ax and every HEAT shell M830Ax, even when they're radically different. M830A1 is a subcaliber, saboted projectile with a streamlined profile. M830 is full-caliber cylinder with fuse sticking out of it. This is one of the better sources of shell pictures on the internet, even though (oddly...) it's in Russian.

What's the auto-reload problem, in your view? AI tanks are able to reload their guns without a problem, what I said earlier was false. For player tanks, the commander is always in charge of the reload cycle. If you spawn as gunner, your gun will automatically reload. If you spawn as commander, you must hold down the space bar and push the reload key after every shot. I want to automate the last bit, but the script commands to do so simply do not work. Action "LOADMAGAZINE" doesn't do anything no matter how I try to use it, and calling "reload" after every shell just results in the loader reloading 2800 rounds into the coaxial, which I've decided should take a couple minutes of fiddling with ammo cans. (How long should this really take? Five/ten minutes?)

I don't have a clue about VBS2. There's a good chance that the -mod switch doesn't do anything, even if by some miracle this was compatible.

Well, I think I'm about to go off and try to crash ArmA with canister rounds. I wonder how many pellets I can make it track...

[Kizzma 0]

I do have a folder called addons inside of the @NWD folder, and it is "ca/addons". Is that a problem? Should it just be Addons inside the VBS2 folder?

[Maddmatt 1]

I do have a folder called addons inside of the @NWD folder, and it is "ca/addons". Is that a problem? Should it just be Addons inside the VBS2 folder?

Give it a try. I don't know, I only have ArmA. The mod might need changes to work with VBS2.

I see a folder for my ArmA Effects mod there. Does that work? It should be installed the same way.

[Kizzma 0]

The ArmA Effects mod does work, and I essentially did the same thing, which is why I am confused.

[Maddmatt 1]

The ArmA Effects mod does work, and I essentially did the same thing, which is why I am confused.

Last idea I have is to make sure the extended init and fired eventhandler addons are in an addons folder.

Maybe because the VBS2 tanks are different to the ArmA tanks in some ways, it messes up the mod. I think this addon would have to be modified to work with the VBS2 tanks.

[NonWonderDog 0]

I'd assume the VBS2 tank is called something other than "M1Abrams" in the code, then. I don't know if my script would be compatible in any case.

[frederf 0]

You said that the proximity fuse on the tank shells wouldn't detect land but if you added in a check for height AGL, then that should cover 90% of all the terrain proximity issues for shells, allowing them to explode in prox to terrain.

[NonWonderDog 0]

Yeah, but it won't work. I'm not sure why, but <table border="0" align="center" width="95%" cellpadding="0" cellspacing="0"><tr><td>Code Sample </td></tr><tr><td id="CODE"> if (((position _shell) select 3) < _proxrange) then

{

_detonate = true;

_hintstring = "Fuse triggered by terrain";

};

is never triggering.

Because I'm an idiot. "select 2"

Proximity fuses will be triggered by terrain in the next version...

[Apache-Cobra 0]

Great work. Much MUCH better than stock ArmA tank system... I BEG you to do more work with the tank system... anyone else with me?

[Canalien 0]

Ah I see, my mistake... So in the default load out there's no use for the HEAT FCS mode because there are no M830 HEAT-MP-T shells in the tank... only M830A1 and APFSDS.

That makes more sense if it's the case... any possibility of having the script detect exactly which shells the tank is equipped with at any given time and restricting FCS modes accordingly?

(ie... if there are no M830 shells, don't give the HEAT option at all)

Or am i still misunderstanding?

[NonWonderDog 0]

I didn't expect this, but ArmA has absolutely no problem whatsoever with canister rounds. I can generate 1100 high-velocity high-drag projectiles, all at once, and even have them bounce around wildly. With no stutters. (Obviously, this might depend on your hardware...)

Now all I need is a good normal distribution algorithm. My current method makes a big circle of loosely organized pain. What I need is concentrated pain, with pain around the edges....

*Squee!*

Of course, the tracers are just for testing. But you can clearly see that it's a Gaussian distribution. It's coming out of the coax right now, though... that will be hard to fix.

I don't really know how big the dispersion pattern should be, and I think it's probably classified. I'm open to suggestions, preferably in the form of a one-sigma circle.

That makes more sense if it's the case... any possibility of having the script detect exactly which shells the tank is equipped with at any given time and restricting FCS modes accordingly?

(ie... if there are no M830 shells, don't give the HEAT option at all)

It's possible, but it gets awful complicated whenever I try to think it through (in anything except a very hardcoded case that would make it too hard to expand my ammo list, that is). I'll figure it out eventually.

[Canalien 0]

Haha sweet crowd mangling fury.

Well if that's too easy for you, how about simulating some of that sweet six-way programmable Bofors 3P 40/57mm ammo (not that you can use it any either of these tanks)... just kidding :P

[343rdBadger 0]

NW Dog...is there any way we can get a quick and dirty intergrated update inorder to test your mode in arma xtreme1.3?

I'm really really missing the ambiance, textures and command interface that we get in that mod.

hmmmm...forget above post...I just loaded a multiplayer lan mission arma xtreme and it worked???Strange it didn't show up before?

[mrcash2009 0]

I notice the target wont show with XAM 1.3 any chance of tweaking this or a workaround so both can work with each other, this mod is superb, combined fully with XAM would be spot on.

[milobr 0]

Actually I found out that it can be used along with XAM, but you must have enemy units in the field. I think you need to have or infantry or armoured, but I'm not sure of that as sometimes it works and sometimes it doesn't.

[mrcash2009 0]

Indeed you are correct sir, all working with XAM 1.3

Im loving it, sort of surprises me how this wasn't the vanilla version of the tank system to be honest

This is a superb mod, from my post level im new here and only a month into ARMA itself (needed a new rig to try it) and its a blast (excuse the pun). This Mod is most definitely a firm keeper, cant wait to see it post beta

EDIT: Yes it does seem to work and then not work at times, IE: gunner has target optic one time and all options to Lase etc, then other times no optic on gunner and no Lase options / any additional options.

[Canis 0]

Hi NWD, thanks for the great ballistics mods.

I notice your using Initial velocity of 1100 for the 105 HE (M760?) and airFriction of -0.000300. My ballistics calculations show that 650 ms and -0.000078 is 'about' right for just scratching past the 14k mark at 800 mils. Without RAP the M119 doesnt seem to throw out anything faster than 710 as far as I can tell, and they need special permission for that charge as it hurts the gun a tad (testing??). But info on the net is a bit sketchy so I've had to combine L118, M119, M1 and M760 non-RAP info to get a 'happy' 650 ms high charge shot for the M119+M760. Also I 'think' that they run into shell structure stability problems with the M1 and M760 shortly after the 710+ ms mark due to the charge needed, but as I said, solid info is hard to come by and i'm still tweaking the individual charges. Also I'm a bit of a newb to all this.

I've written an sqf that calculates the projectile trajectory with the ArmA all-in-one air friction coef included, and can feed that data to the M119 AI Arty. I can hit a t72 at 14k and below with this, Non-scripted rounds, using real Arma physics. I'm intrested in your thoughts as I would like my Arty to be compatable with your ballistcs models in the future. (Have I got something Majorly wrong in short?)

Again, thanks for your great work, arma is starting to feel less like a fairground and more like a simulation these days.

[NonWonderDog 0]

Artillery rounds are not finished. Or rather, they're not started. I'm not sure why I have them in this mod. Before I can get really start on them I really need to write a MATLAB code to simulate the ArmA ballistics so I don't have to load the game each time. (Actually, I might have a projectile code I wrote as a frosh that uses the same formulas... Yep, I do. It's now adapted to work with ArmA physics .)

I can say, though, that the airFriction you came up with seems very low. I'm just sitting around with a G&T watching the Wahoos lose, so I'll do some research.

Anyway, if you grab the initSpeed and the airFriction from the config your script should work with any numbers I come up with. Take a look at getNumber if you haven't already. I don't know what names I'll use for the artillery rounds, though, since I'm changing things constantly. I'll make an ArtyBallistics.pbo you can use for whatever purposes you want.

Random research forthcoming:

from Janes:

Ballistic data for the 105 mm HE M1 when fired from M101/M101A1 howitzers is as follows:

Charge 1 - MV 198.1 m/s - max range 3,510 m

Charge 2 - MV 216.4 m/s - max range 4,110 m

Charge 3 - MV 237.7 m/s - max range 4,860 m

Charge 4 - MV 266.7 m/s - max range 5,950 m

Charge 5 - MV 310.9 m/s - max range 7,650 m

Charge 6 - MV 376.4 m/s - max range 9,380 m

Charge 7 - MV 472.4 m/s - max range 11,270 m.

Ballistic data for the 105 mm HE M1 when fired from M102 howitzers is as follows:

Charge 1 - MV 205 m/s - max range 3,700 m

Charge 2 - MV 223 m/s - max range 4,300 m

Charge 3 - MV 247 m/s - max range 5,200 m

Charge 4 - MV 278 m/s - max range 6,300 m

Charge 5 - MV 325 m/s - max range 8,100 m

Charge 6 - MV 393 m/s - max range 9,600 m

Charge 7 - MV 494 m/s - max range 11,500 m.

Range data for the L119/M119A1 Towed Howitzer when firing the 105 mm HE M1 is as follows:

Charge 1 - range 1,800 to 3,400 m

Charge 2 - range 2,100 to 4,100 m

Charge 3 - range 2,600 to 4,800 m

Charge 4 - range 4,100 to 6,300 m

Charge 5 - range 4,200 to 7,900 m

Charge 6 - range 5,000 to 9,500 m

Charge 7 - range 6,200 to 11,500 m.

China North Industries (NORINCO)

Type: 105 mm HE

Description: Projectile weight given as 18.12 kg with length 789 mm. Filled with 2.31 kg of

Composition B or 2.18 kg of TNT. Muzzle velocity 494 m/s. May be fitted with standard NATO fuzes.

No other information available although stated to be compatible with standard NATO howitzers

Yugoimport SDPR

Type: 105 mm HE M1

Description: Essentially the same as HE M1. For 105 mm M56 howitzer, from which it is fired using a

seven-charge propellant system plus a Super Charge. Maximum muzzle velocity is 570 m/s and

maximum range 13,000 m. May no longer be in production

Range data for the 105 mm L119/M119A1 Towed Howitzer when firing the WP/Smoke M60 is as

follows:

Charge 1 - range 1,800 to 3,400 m

Charge 2 - range 2,100 to 4,100 m

Charge 3 - range 2,600 to 4,800 m

Charge 4 - range 4,100 to 6,300 m

Charge 5 - range 4,200 to 7,900 m

Charge 6 - range 5,000 to 9,500 m

Charge 7 - range 6,200 to 11,500 m.

Yugoimport SDPR

Type: 105 mm Smoke/WP M60

Description: Essentially the same as WP/Smoke M60. For 105 mm M56 and M18/61 howitzers (a

modernised version of the Second World War German 105 mm leFH 18), it is fired using a

seven-charge propellant system plus a Super Charge. Maximum possible muzzle velocity is 570 m/s and

maximum range 13,000 m, although the normal muzzle velocity is given as 491 m/s and maximum

range 11,620 m. Complete round weight given as 20.049 kg and projectile weight 15.8 kg. May no

longer be in production

Range data for the 105 mm L119/M119A1 Towed Howitzer when firing the 105 mm Illumination

M314 is as follows:

Charge 1 - range 1,800 to 3,400 m

Charge 2 - range 2,100 to 4,100 m

Charge 3 - range 2,600 to 4,800 m

Charge 4 - range 4,100 to 6,300 m

Charge 5 - range 4,200 to 7,900 m

Charge 6 - range 5,000 to 9,500 m

Charge 7 - range 6,200 to 11,500 m.

Maximum illumination range is 8,700 m (minimum 400 m).

Illumination: 400,000-450,000 cd

Burning time: up to 60 s

From random disreputable websites:

For comparison the 105mm M119 gun fires the 14.97 kg M760 HE round at 633m/s to 14,500m.

Projectile Current Max Range Current MV Limits

M927 HERA 15 Km 496.6 M/S

M916 DPICM 14 Km 488.4 M/S

M915 DPICM 14 Km 637.3 M/S

M913 HE RA 19 Km 673.3 M/S

M760 HE 14 Km 658.3 M/S

M548 HE RA 15 Km 563 M/S

M444 ICM 11.5 Km 497 M/S

M314A3 Illum 11.5 Km 492.4 M/S

M84A1 smoke 11.5 Km 503 M/S

M60 Smoke 11.5 Km 491.4 M/S

M1 HE 11.5 Km 502.4 M/S

M2/M101 Howitzer graphical firing tables:

http://www.rekeninstrumenten.nl/pages%20and%20pictures/04401.jpg

http://www.rekeninstrumenten.nl/pages%20and%20pictures/04421.jpg

http://www.rekeninstrumenten.nl/pages%20and%20pictures/04441.jpg

I'll try to fit the curves to the firing tables, and then add 4.5% to the muzzle velocity for the M119. If these are really M2 firing tables, though, that 11.5 km at 800 mils figure thrown about is just flat wrong. These show 12.1 km at 700 mils. For a shorter-barreled M2 howitzer. It's probably a doctrinal thing, i.e. there's not enough room to adjust fire on a target more than 11.5 km away.

[.kju 3244]

Quote[/b] ]OFP demo models, a modiffied BIS Arbams to be precise - had the lods reworked and config changed. Not on ftp anymore but the changes were described by Przezedzieblo (sp?) in the pages I've mentioned.

That should be the addon:

http://mihd.net/wcj6oa

PS: Decompress it with PBO Decryptor v1.5.

ofpec link