Airsoft Howitzer.

[SheriffHD]

Ok, We really need to see something like these on UK sites. WOuld make for a brilliant scenario game and the whistles of them falling down would be epic.

I mean would need to calculate PSI + Projectile Weight + Angle of Trajectory to calculate what force it could potentially hit some one with. and then try to get it into a safe limit, but still It would be sweet as hell to have in a game. even better if you had like 10 of em manned and firing.

Any way, here is the video

 

[remus]

man do i want.

 

[joshcowin]

i seen this ages ago and still watch it now thinking yep i want one

 

[SheriffHD]

Just picture the game mode. like 5 or 8 of these lined up next to a few bunkers, Objective is to capture the base. all the while you just hear the whisteling as the nerf rockets fall from the sky, with the loud Bang of the howitzers going off in the back ground. while the defensive team can request a position by smoke grenade for them to focous on. would be epic. or even start the match of by all 8 firing smoke grenades into the middle of the field.

 

[QuadMachine]

That is frankly awesome. Scouts in the field could chart positions and radio back fire for effect orders. There could be a kill zone rule where anyone caught in a 30 yard radius takes a hit, and within 15 takes a hit regardless of cover.

 

[Zak Da Mack]

Did a bit of research, the item used is a Nerf Vortex Mega Howler.

Apparently, it weighs 220g. If we was to fire it in the air, then there will be a point in which the momentum is lost to allow it to fall back to the ground.

So, depending on the max velocity gravity allows this thing to go whilst falling, I could see it being used as a projectile that would be safe for people to get hit by.

Just thought, isn't momentum the thing we need to worry about more than velocity? Becuase if an item has more momentum, doesn't it have more striking force behind it?

 

[AirsoftTed]

I've actually been making plans to make a mortar that fires a similar thing for safe use. Would be great if we could roll stuff like this out in the UK!

 

[remus]

Did a bit of research, the item used is a Nerf Vortex Mega Howler.

Apparently, it weighs 220g. If we was to fire it in the air, then there will be a point in which the momentum is lost to allow it to fall back to the ground.

So, depending on the max velocity gravity allows this thing to go whilst falling, I could see it being used as a projectile that would be safe for people to get hit by.

Just thought, isn't momentum the thing we need to worry about more than velocity? Becuase if an item has more momentum, doesn't it have more striking force behind it?

put it this way, itll hit the ground with as much force as it has when it leaves the cannon(what gravity takes away it gives back) course being a nerf ball id only be worried of the unlikely event of it comming down right in someones face and knocking their googles off.... as for play use what do ya do, if it lands near you do you take a hit, how near etc? think you could mod a nerf ball so that when it hits the ground it releases smoke/ bbs ?

 

[ScoobySnacks]

Remus, you're forgetting the fairly significant component of air resistance (drag)

These things have a significant soft front end, so even hitting fairly hard they'd not hurt. Also, the whistles and the shape help to reduce the terminal velocity. I can't foresee this doing any damage to anyone, unless they actually sit on the end of the barrel while it's fired.

As for momentum, the thing that actually does the damage is energy. This is a direct function of velocity and mass. As mass is fixed, and the terminal velocity is fairly constant, the terminal energy is fixed.

You'd need a fairly big field to use it in, but I don't see much risk with the projectile (except it'd be expensive as you'd be bound to lose loads, and would be a PITA finding them all at the end of the day)

 

[SheriffHD]

.....Guess you guys didnt pay attention to science class. E=MC2 (energy = Mass x Velocity squared)

So to calculate the amount of energy in the projectile we need to calculate the total amount of energy (in this case Ft/lbs)

Which to do so it would be 220(mass) x 140(velocity/ This is just a random number) x 140 / 450240(this is the constant to determine Kinetic energy) = 12.98J or 9.58Ft/Lbs

 

[geoffreym]

.....Guess you guys didnt pay attention to science class. E=MC2 (energy = Mass x Velocity squared)

So to calculate the amount of energy in the projectile we need to calculate the total amount of energy (in this case Ft/lbs)

Which to do so it would be 220(mass) x 140(velocity/ This is just a random number) x 140 / 450240(this is the constant to determine Kinetic energy) = 12.98J or 9.58Ft/Lbs

I can't fault the maths on this, however you haven't taken drag or design in to account, I used to have one of nerf vortex's, and it was damn hard to hurt someone with it. I believe 13 joules is more along the lines of air guns.

 

[SheriffHD]

no but its all the math insurance companys will care for. which is the biggest issue to use this in a game. the rest of the math is variables (for instance an airsoft rilfe is limted to 330fps in most places. which gives you 1.2j of energy at its peak. over distance it will decrease. but insurance purpose they care more for the worse amount it can do. The same would apply for this.

But Im going to do all the math now to see how far you could get one under a reasonable insurable limit.

(also my math is wrong, I calculated with the wrong weight unit, and also, you need to remember that Piantball guns hit at about 13J too.)

 

[Ian_Gere]

Mate E=mc² means the total energy (E) contained within some matter is equal to its mass (m) x the speed of light [c) squared (²) - Nuclear Physics

Momentum = mass x Velocity Newton's 2nd Law

But the crucial measurement is N/m² where N is the Force (in Newtons) applied to the area of the target which is hit (in meters squared)

Force is the energy necessary to accelerate a given mass, so it is measured as Kilogrammes x meters / second squared (SI unit Newton = 1Kg x 1m / 1s²)

I'm afraid my certain memory runs out there, but I've a feeling that, for our purposes at least, mass x velocity / meter² is what we're after. We need Tariq to chip in and clarify things. I think that the Nerf football squidginess is expressed mathematically in this case as a modification of our velocity and target area as, by the time the full energy of the mass is applied, the tip has flattened out slowing the whole thing down...

 

[SheriffHD]

Mate E=mc² means the total energy (E) contained within some matter is equal to its mass (m) x the speed of light [c) squared (²) - Nuclear Physics

this may just be me interpreting it wrong, but the sentence looks as it you are disproving of my statement.. But yes you are correct, In Einsteins E=MC2, C means the speed of light which is the constant, But in applicable science you are taught E=MC2 where C means Velocity. the equation is the same but you are changing the meaning of C, which is why you have to add an additional constant, in this case the Magic number 450240, this is how you work out Kinetic energy.

as well with most ballistic projectiles measurement has a trend of being in Joules and Foot pounds of Pressure. In airsoft we use FPS and J, same with firearms.

I wont lie, my scientific mind has been fried just from being used this much already.

 

[remus]

do you think its even possible to get a nerf ball to go hard enought o hurt someone? despite the face i never did any work in my alevel maths im prettysure theres a max speed even with g etc and the overall mass of a nerf ball being so low due to density... and anything powerful to get the nerf high enough for it to occur, well if you can get the nerf to then land on site then you should likely win on merrit.

and yea i forgot general friction and was thinking of the ke=pe equation which dosent take into account that minor niggle...

 

[Ian_Gere]

Well, I've never come across "c" being used as anything other than the speed of light, but I'm prepared to accept that something like that could be right. After all Force and Pressure have acceleration so m/s². From wiki:

 

[TPI]

*Sees letters being used in Math's Promptly leave's Topic*

 

[Ian_Gere]

Realistically I think the only danger could come from being hit by it soon after it leaves the barrel.

 

[remus]

make the barrel higher than people then. course if someone sticks their head in front of a huge cannon.... . have a no firing if enemy in x distance or something too( as you really shouldnt anyway as youd ignore the unseen target and try to shoot/run away from them anyway. ya know we discussed briefly E=mc2 in psychics, never actually used it... never really was suited to answer any of the questions we were supposed to be doing.

 

[SheriffHD]

Anything going fast enough can be deadly, Pretty much the one thing mythbusters has taught me lol