Physical Combat Data

[Faerúth]

Hello brothters and sisters of the @ 
I am currently working on a combat system for my roguelike, Faded Prophecies, and need some help.

The game features a material system and the damage is determined by physical data like the energy of a hit and the hardness of the weapon's material. The damage calculation seems to work, but the tricky part is balancing the whole thing.

The biggest problem (at least for now) is my lack of some realistical physical data of that fighting stuff. I am mostly looking for the following:
-the velocity with which an average sword (ca 1,5kg) is swung
-the energy and velocity of an average fist strike and a kick

Has anybody an idea where I could find information like this??

[Hi]

Punch a pendulum as hard as you can. The distance that the pendulum goes up is the amount of energy that you managed to put into it.

[Etinarg]

I have no such data ...

Instead of energy, I'd see damage proportional to momentum (p=mv) divided by the area of impact ... so more or less

dam ~ (m*v) / A

That still leaves you with the question for data. But it makes pointy weapons more likely to do damage ... if you want that. In reality this was used to create armor breaching weapons. You may or may not want to model this detail. If not, just leave out the area modifier.

[Faerúth]

Punch a pendulum as hard as you can. The distance that the pendulum goes up is the amount of energy that you managed to put into it.

Hmm, I don't think I have the right equipment to make such experiments with proper results, but maybe with some improvisation I could at least get inaccurate values. But I will first do a bit of research for more exact ones.

I have no such data ...

Instead of energy, I'd see damage proportional to momentum (p=mv) divided by the area of impact ... so more or less

dam ~ (m*v) / A

I use different formulas for different types of damage (blunt, cut, pierce). With adding the area component I would get only the amout of pressure, which is most important for pierce damage.
We calculated some examples in physics class once, and came to the result that a woman on high-heels produces more pressure than an elephant standing on all of his feet. But I think the elephant should inflict more damage when standing on top of you
But thanks for mentioning momentum, I forgot that I need this for knock-downs 

[getter77]

This is something of a longshot of my memory, but I'm fairly sure I recall specific value being given for this in an episode of the TV series Mythbusters during one of their topics on Samurai vs Western Swords, as they had to program/calibrate a machine to to appropriate values for the live testing.  I'd suppose you can find the episode somewhere off their/Discovery's site?

Seems like I recall similar from some other show on Discovery some years back dealing with Martial Arts, probably not Mythbusters.

[Faerúth]

Hi,
I just found a promising article about the physics of matial arts which seems to contain everything I need.
Actually, it was the first site that showed up when I googled "martial arts physics".
I'll need a dictionary for the physical terms, but it's obviously more effective not to search only for sites in one's native laguage 

Thanks @ all 

[purestrain]

Don't forget to add the possibility of friction due to wind/rain/dust to your calculations

[Darren Grey]

And cetrifugal forces from the earth's rotation 

[Vanguard]

-the velocity with which an average sword (ca 1,5kg) is swung

The velocity should be the speed that the person's hand is moving at divided by the length of their arm, and multiplied by the length of their arm added to the length of the sword.

I have to ask though, are you certain this is the approach you want to take?  Maybe you have something unique in mind for the gameplay, but if not, giving a sword an attack power of 40 (or whatever) is an easier approach.

Take a look at dwarf fortress.  Adamantine used to just do 5x damage, and it worked great.  Now Toady is trying to use simulated physics for damage, and it's all messed up.  Adamantine is a mediocre weapon material, and the best possible weapon is a giant slab of stone with a handle attached to it.

[Faerúth]

The system I currently use is less realistic than that of DF, it uses abstract values for material hardness and flexibility. Also the armor values are just percents of damage-reduction based on the material properties.

After a bit of playing with numbers it seems to be quite balanced. For example "a giant slab of stone with a handle" is a fairly weak weapon, because only a giant would have the power to swing it effectively 
And for strenghtening materials like adamantine can use magic.

I made a diagram that shows how the weapon's mass influences the energy with which an average human would hit:

[Vanguard]

Sounds like it's working pretty well then.  Good luck to you!

[dungeonmans]

Faeruth this is pretty cool, I hope your math continues to work out the way you want it to. I agree with Vanguard that you should be careful not to confuse things too deeply but it looks like you have that covered.

I'd like to know, are you using properties of sharpness in your damage calculations as well? For example, say you have a Steel Sword and a sword made of Sharponite or something that is really light but really sharp. That steel sword weighs more but would bounce off some armors, where the Shaponite sword would cut through them even with little effort.

Maybe "sharponite" is confusing, but let's say then a Vorpal weapon, or a Lightsaber, or even a mithril sword which is incredibly light and sharp.

[Faerúth]

Thanks, dungeonmans 

I don't use a sharpness property for now, for the calculations I assume that the weapon is sharpened as much as possible and that the hardness of a material determines the maximal sharpness. I don't know if that is realistic, though, so there might be changes...