Math formulas
 

I'm interesting in math formulas that describe the possibility to hit unit and destroy (for example tank). If anybody knows such formulas, I will be grateful for sharing knowledge.

Re: Math formulas
 

Look, the designers won't just give you the formula yourself; you have to do some experimentation to find it yourself using MOBHack.

Re: Math formulas
 

I did work out a formula that pretty closely simulates the penetration used in game though if that's what you're looking for

Re: Math formulas
 

Mark, Can you post it?

Re: Math formulas
 

Mark, Can you post it?

Okay let me take a stab at converting it into a form that works well on a forum:

Here's the numbers that I've found through testing.

5% percent of range = 100% Penetration
10% percent of range = 100% Penetration
15% percent of range = 100% Penetration
20% percent of range = 100% Penetration
25% percent of range = 82.5% Penetration
30% percent of range = 79.6% Penetration
35% percent of range = 75.8% Penetration
40% percent of range = 72.8% Penetration
45% percent of range = 71.2% Penetration
50% percent of range = 66% Penetration
55% percent of range = 62.8% Penetration
60% percent of range = 60% Penetration
65% percent of range = 55.6% Penetration
70% percent of range = 52.8% Penetration
75% percent of range = 49.8% Penetration
80% percent of range = 46% Penetration
85% percent of range = 42.6% Penetration
90% percent of range = 39.6% Penetration
95% percent of range = 35.4% Penetration
100% percent of range = 33% Penetration

So let us say we want to find the penetration of a weapon with say a 5 AP penetration and a range of 20, at say, 50% of it's range?

Firstly, we take the range (20) and multiply it by 50 to get the weapon's maximum range in meters, which is:

20 x 50 = 1,000 meters

50% of the weapon's maximum range is:

1,000 x 0.5 = 500 meters

Now we can figure out the penetration.

The penetration at 50% of the range is 66%; so

AP Penetration (5) x 0.66 = 3

So at 500 meters, the weapon will have a penetration power of 3.

Please note that this is the *AVERAGE* penetration; you'll find from time to time, your weapon will penetrate a little less or a little more, and a few times will massively overpenetrate or underpenetrate; I *think* the frequency of these occurences and how often they favor over or under penetration is linked to warhead size.

I *think* this is SPCAMO's way of simulating the effects of shell diameter vs armor thickness; the Soviet 122mm gun in WWII was very effective against German Heavy Armor because the shell diameter at 122mm was bigger than the armor thickness that was opposing it.

Re: Math formulas
 

Every now and then, someone asks for these details, and we have to tell them we cannot divulge them as that proprietary info was embargoed as part of the deal with SSI when releasing the code.

There is however, no restriction on back-calculating the formulae from the game results and stats as others have already attempted to do.

Cheers
Andy

Re: Math formulas
 

Nope! But here is a suggestion. Traditional tactical boardgames provide various hit-penetration-etc tables as the player must do some calculations and/or cross reference the die result with some form of result table. So if you're clueless as to how to start a "reverse engineering" ordeal, tactical boardgames may be a good starting point.
And of course there is the Pentagon...

Re: Math formulas
 

Hi,

I pressume that you wish to modify the existing scientific penetration formulas into a WinSPMBT game suited formula?

The simplest penetration model (from the three that I am aware of) is the Anderson equation (or for a more complicated model you may seek the Lanz-Odermatt equation).

Here is the very basic formula of the Anderson equation:

P =(1.044*V -0.194*Ln (L/d) -0.212 ) * L

V: velocity (Km/sec)
L: length of the penetrating rod (mm)
d: diameter (mm)
P: depth of armour penetrated (mm)

cheers,
Pyros

Re: Math formulas
 

Holy @#$%, Am I in the right forum? This looks like a Mensa club meeting or rocket science forum. This is too much for my Infantry Grunt brain to handle! [img]/threads/images/Graemlins/icon07.gif[/img] http://forum.shrapnelgames.com/images/smilies/egg.gif http://forum.shrapnelgames.com/image...es/biggrin.gif

Re: Math formulas
 

P =(1.044*V -Ln (0.194*L/d) -0.212 ) * L

i've got some questions tp this formula!
1. what does the constants discribe?
2- "-ln" because the projectile becomes slower, but why L/d?

Re: Math formulas
 

Holy @#$%, Am I in the right forum?

Yes you are. http://forum.shrapnelgames.com/images/smilies/happy.gif

This looks like a Mensa club meeting or rocket science forum. This is too much for my Infantry Grunt brain to handle!

It's actually a quite easy formula to understand, it's basic algebra; unlike a lot of other formulaes out there http://forum.shrapnelgames.com/image...es/Injured.gif

Re: Math formulas
 

Actually, you got the formula wrong.

It's really

Anderson:
P = 1.044 x V - 0.194 x Ln(L/D) - 0.212 * L

V: velocity (Km/sec)
L: length of the penetrating rod (mm)
D: diameter (mm)
P: Penetration

HOW TO DO IT:

Now to provide the numbers:

V = 0.81 (810 m/s) = Velocity
L = 370.05 = Length of Penetrator (mm)
D = 88 = Diameter of Penetrator (mm)

Roughly that of a German 88mm L56 shell.

So we've got the following equation now:

1.044 x 0.81 - 0.194 x Ln(370.05/88) - 0.212

First thing first, we need to solve the Logarithimic problem; excel is great for those of us who did not pay attention in Math; it has a Logarithm function.

370/88 in Logarithimic is: 1.4363

So now the Formula is:

1.044 x 0.81 - 0.194 x 1.4363 - 0.212 * 370.05

Something that you can solve with basic infantryman math.

That formula results in

131.36mm penetration.

That's actually quite close to the actual performance of the 88mm L56 Panzergranate 39 round; which was 120mm of armor at 30 degrees (139mm total) at 100m.

Re: Math formulas
 

MarkSheppard,

Thanks, I already corrected the typo error of the formula. http://forum.shrapnelgames.com/images/smilies/wink.gif
(btw, you should make a small correction in the formula that you posted because I think that the L is a divider of the penetration, not just a multiplier of the 0.212)


Just to give some depth to the discussion I will add some more parameters to the basic model of Anderson's equation:

Anderson Equation:

P/L = 1.044 x V - 0.194 x Ln(L/d) - 0.212

V: velocity (Km/sec)
L: length of the penetrating rod (mm)
d: diameter (mm)
P: Penetration(mm)


1. The first condition of this formulae is that the velocity should be around 900 m/s and 1800 m/s.

2. Next we should add a modifier (multiplier) for the material of the penetrator (for instance STEEL 0.5, TUNGSTEN 1.0 and DU 1.13)

3. Finally there is also a modifier for the equation related with the scaling factor of the penetrator diameter [Scaling factor = 1+(d/6.5 x 0.05)]

So, the full equation after adding all the above parameters will be as following:

P/L = [1.044 x V(km/sec) - 0.194 x Ln(L/d) - 0.212] x [1+(d/6.5 x 0.05)] x (multiplier for material of penetrator)

Be careful to adjust your Muzzle velocity with the correct V drop (per trajectory flying distance).

You should also add in the above formula the parameter of the "Angle of Obliquity".

At an impact of 60 degree the penetration capability is halved in comparison with an impact at 0 degrees.

http://www.navweaps.com/Weapons/Gun_...iquity_pic.jpg

cheers,
Pyros

Re: Math formulas
 

Tanknet scientific forum revisited. http://forum.shrapnelgames.com/images/smilies/happy.gif

Re: Math formulas
 

Where's the mass of the projectile or density or whatever?

Re: Math formulas
 

This is indeed a good place full of info concerning ballistics http://forum.shrapnelgames.com/images/smilies/wink.gif

cheers,

Re: Math formulas
 

Here...

The Odermatt equation

Re: Math formulas
 

Thanks Mark. Helped a lot.

Re: Math formulas
 

All these formulas are empirical models because it is extremely difficult to design a theoretical model describing the effects of penetration (in relation with the modern warheads and synthetic armor plating).

The principle scientific field which is used for the analysis of the modern ballistic research is the hydrodynamic behaviour (fluid mechanics) of the materials during a hyper-velocity penetration.

cheers,
Pyros