478 replies to this topic

[Y E O N N E]

Nightbird, on 11 March 2018 - 09:37 AM, said:

Those are all fine these limitations are in the shooter after all, and a mech managed by a targeting computer would not be as affected = reduced weight of the weapon?

They are not fine. The limitations are not the shooter, because the shooter is what you have to work with. The same thing applies to 'Mechs. Both the shooter and the 'Mech are a part of the firing system in their respective examples, and both of them have to find some way to brace themselves for the recoil. Standing, as 'Mechs do, is the least stable firing position. There is nothing you can do to overcome the fact that an AC/20 or Gauss Rifle mounted high up in the arm or torso of a 'Mech like the Rifleman or Hunchback is going to try and topple the whole thing over because it has that long moment arm to act on. No muzzle brake is going to change that and the energies are just too high for an active recoil cancellation system like the ones you might find on small arms. Remember, an AC/20 is firing things like ten 150 mm rounds or two 203 mm rounds in the span of 10 seconds. Unless those rounds are made of similar super light materials (which would make absolutely no sense for the intended purpose and would just require an increased propellant charge anyway), the recoil is going to be literally staggering.

The 'Mechs are just not massive enough to fire weapons like these at the rates that they do, if at all, and certainly not while moving. That's why I re-write the canon. It really, really doesn't work unless you do this.

[Nightbird]

It's OK to be less capable than a purpose built killing machine...

[Y E O N N E]

Nightbird, on 11 March 2018 - 01:06 PM, said:

It's OK to be less capable than a purpose built killing machine...

I...don't think you know at all what you are saying.

The recoil is applying torque along the lever that is the 'Mech's body. Fire big gun mounted at the top of that lever, which also happens to be super light weight, and you knock the lever over. The end.

[Nightbird]

If the round being fired is the same, the total recoil from shooting is the same regardless of weight of the rifle by newtons third law.

Why does the 'kick' from a lighter weapon feel sharper? Because the bracing of the rifle is imperfect, there is human flesh between the butt of the rifle and the solid human skeleton. As a result this imperfect bracing, the rifle is allowed to accelerate against the body, pinches the flesh in between, and causes discomfort with the 'kick'. Cutting the weight of the rifle in half would double the sharpness of this kick.

A robot on the other hand has no such flesh. The rifle wherever it is mounted is one with the rest of the body, preventing the rifle from accelerating against the body. Instead, the body and rifle together would absorb the recoil without this imperfection, so even cutting the weight of the rifle in half would only change the total weight of the recoil absorbing system by a tiny percentage.

Edited by Nightbird, 11 March 2018 - 02:18 PM.

[0Jiggs0]

Nightbird, on 11 March 2018 - 01:50 PM, said:

If the round being fired is the same, the total recoil from shooting is the same regardless of weight of the rifle by newtons third law.

Why does the 'kick' from a lighter weapon feel sharper? Because the bracing of the rifle is imperfect, there is human flesh between the butt of the rifle and the solid human skeleton. As a result this imperfect bracing, the rifle is allowed to accelerate against the body, pinches the flesh in between, and causes discomfort with the 'kick'. Cutting the weight of the rifle in half would double the sharpness of this kick.

A robot on the other hand has no such flesh. The rifle wherever it is mounted is one with the rest of the body, preventing the rifle from accelerating against the body. Instead, the body and rifle together would absorb the recoil without this imperfection, so even cutting the weight of the rifle in half would only change the total weight of the recoil absorbing system by a tiny percentage.

A lighter weight rifle has a "sharper kick" not because of the human body, but because the mass of the rifle has been reduced. Reducing the mass of the rifle means the kinetic energy generated by the propellant travels more efficiently through the body and mechanisms of the rifle, thus delivering more energy into the firer's shoulder. A heavier rifle would absorb a greater amount of this energy, and reduce the amount of felt recoil. The same principle applies if the weapon is fixed to a robot. Reducing the mass of the weapon would increase the amount of force applied to the weapon's mount. If the mount or mounting surfaces cannot handle the forces applied to them, the weapon tears free. Even if the mount can handle the strain, the greater force applied to the mount will still be imparted upon whatever body the mount is a part of. If it were a shoulder mount, like the Rifleman's, a violent rotational force along the torso would be expected. The point is that kinetic energy has to be absorbed by something in order to avoid these kinds of problems.

[Y E O N N E]

Nightbird, on 11 March 2018 - 01:50 PM, said:

If the round being fired is the same, the total recoil from shooting is the same regardless of weight of the rifle by newtons third law.

You need to turn in whatever degree you have because that's a willful misapplication of the laws of motion. The energies coming from the weapon are the same, yes. The resistance to motion by the parts of the system involved, however, are not.

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Why does the 'kick' from a lighter weapon feel sharper? Because the bracing of the rifle is imperfect, there is human flesh between the butt of the rifle and the solid human skeleton. As a result this imperfect bracing, the rifle is allowed to accelerate against the body, pinches the flesh in between, and causes discomfort with the 'kick'. Cutting the weight of the rifle in half would double the sharpness of this kick.

We're not talking about the rifle traveling a set distance between starting position and your shoulder. We are talking about its willingness to be moved at all. It's sharper because the rifle is less capable of resisting motion all by itself. You can brace it all you'd like, as a human shooter or on a remote setup, the total system mass is still less capable of resisting the thrust generated by the round leaving the barrel; it's just going to be harder on the mounts both at the gun and at the point where the platform is anchored to the ground. The shock absorbance from your flesh is actually a good thing in this case, because it gives you, the shooter, more time to compensate from the sudden force during firing. Hard, unflinching mounts do not do this and in fact degrade accuracy to a considerable degree. They learned this very quickly at the turn of last century.

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A robot on the other hand has no such flesh. The rifle wherever it is mounted is one with the rest of the body, preventing the rifle from accelerating against the body. Instead, the body and rifle together would absorb the recoil without this imperfection,

Still wrong. A 'Mech is not a homogeneous block. Its weapons are on mounts which have to be able to take the strain of the weapon firing and, often, facilitate the changing of the weapon's elevation and bearing. To not kill or otherwise incapacitate the pilot with vibrations and noise, you also need shock damping in various places. There is going to be some give in these systems.

And even after all that your 'Mech still stumbles, falls over, and gets ganked by infantry because you still had to absorb the equivalent of ten artillery shells firing without adequate time to brace, absorb the recoil, resettle, and aim for the next shot in the volley all at the top of a fairly long pole arm with nothing behind it to keep it propped up.

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so even cutting the weight of the rifle in half would only change the total weight of the recoil absorbing system by a tiny percentage.

Holy f*ck, what a statement.

Let's say I have a rocket with a dubious, physics-defying reactionless drive. If I cut the mass of a rocket in half but still push on it with the same force, what happens? I accelerate at twice the rate, because A=F/M. The energy in the part being accelerated has literally doubled because E = 0.5M(V^2).

e.g. If force constant F is 10 N and mass variable m is 5 kg, then acceleration is 2 m/(s^2). If m is 2.5 kg, then a has to be 4 m/(s^2). If we only accelerate for 1 second in each case, I end up at...2 m/s and 4 m/s velocity. The final energies, therefore, are 10 J at 5 kg mass versus 20 J at 2.5 kg.

Now increase the force by a few orders of magnitude and cut the time frame down to an impulse, a tiny fraction of a second, and apply it straight into your arm at the top of your 'Mech.

TYL: A 100% increase in acceleration is a "tiny percentage".

[Nightbird]

Why do you say the rifle has a kick, and not that barrel has a kick into the stock of the weapon? Because it's one rigid entity.

Likewise, if a rifle is installed into a robot, it and the torso/arm it's installed in becomes one rigid entity. It's mass is combined for the calculation of recoil acceleration.

The human body + rifle will never be one rigid body, though the fact you want to brace as well as you can is to reduce the room that the rifle gets to recoil against you.

You're welcome to insult as much as you want, science is what it is

[Necromonger Commander]

They are leaving lights too small to make them playable. Remember in table top a light cannot beat an assault, ever.

[adamts01]

Nightbird, on 11 March 2018 - 03:38 PM, said:

Why do you say the rifle has a kick, and not that barrel has a kick into the stock of the weapon? Because it's one rigid entity.

Likewise, if a rifle is installed into a robot, it and the torso/arm it's installed in becomes one rigid entity. It's mass is combined for the calculation of recoil acceleration.

The human body + rifle will never be one rigid body, though the fact you want to brace as well as you can is to reduce the room that the rifle gets to recoil against you.

You're welcome to insult as much as you want, science is what it is

build an AC20 Hellbringer and watch those barrels recoil as they fire. I don't know how this comment originated but your assumption is false. MWO seems to use similar recoil technology as modern cannons.

[Y E O N N E]

Nightbird, on 11 March 2018 - 03:38 PM, said:

Why do you say the rifle has a kick, and not that barrel has a kick into the stock of the weapon? Because it's one rigid entity.

Likewise, if a rifle is installed into a robot, it and the torso/arm it's installed in becomes one rigid entity. It's mass is combined for the calculation of recoil acceleration.

The human body + rifle will never be one rigid body, though the fact you want to brace as well as you can is to reduce the room that the rifle gets to recoil against you.

The rifle is not a rigid body, either; it has its own internal fittings that fatigue and break with usage. Stock tangs snap off, barrels and breech blocks crack, return springs lose their tension. It's just that the rifle is A.) more of a rigid body than what is using it because it is expecting the recoil to be managed by an external system and B.) the rifle itself is not what we are discussing, we are discussing its effects on said external system. The weapon is one system, the user of the weapon is another system, and together they form a larger system.

This is called "black boxing" and "systems thinking."

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You're welcome to insult as much as you want, science is what it is

It's OK to be less capable than actual engineers.

[Nightbird]

Yeonne Greene, on 11 March 2018 - 03:47 PM, said:

The rifle is not a rigid body, either; it has its own internal fittings that fatigue and break with usage. Stock tangs snap off, barrels and breech blocks crack, return springs lose their tension. It's just that the rifle is A.) more of a rigid body than what is using it because it is expecting the recoil to be managed by an external system and B.) the rifle itself is not what we are discussing, we are discussing its effects on said external system. The weapon is one system, the user of the weapon is another system, and together they form a larger system.

This is called "black boxing" and "systems thinking."

A) is a rifle mounted on a robot having the same rigidity as when braced against a human shoulder?
Should the recoil acceleration be calculated differently between the two?

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It's OK to be less capable than actual engineers.

Actual yes, internet no

[Popcat]

To all the angry people:

To be fair he did give us a glimpse of the mini Atlas which is super cute.

Edited by Popcat, 11 March 2018 - 03:56 PM.

[Y E O N N E]

Nightbird, on 11 March 2018 - 03:53 PM, said:

A) is a rifle mounted on a robot having the same rigidity as when braced against a human shoulder?
Should the recoil acceleration be calculated differently between the two?

1. The same rifle? More rigidity, but with a gigantic amount of relative backup mass...unless you mount it in a recoiling carriage. It is entirely up to the builder how rigid they want that mount.

2. No, because all you need to know for that is the muzzle velocity of the projectile, the projectile's mass, and the mass of everything that is solidly fixed to the breech and barrel because we can reasonably assume the modulus of elasticity and rigidity of those parts is high enough that deformation is negligible. Anything not solidly fixed along the same axis is a damper and will transform some of the energy into heat.

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Actual yes, internet no

It is a good quality you have, then, to admit when you are wrong!

[Nightbird]

Yeonne Greene, on 11 March 2018 - 04:12 PM, said:

1. The same rifle? More rigidity, but with a gigantic amount of relative backup mass...unless you mount it in a recoiling carriage. It is entirely up to the builder how rigid they want that mount.

2. No, because all you need to know for that is the muzzle velocity of the projectile, the projectile's mass, and the mass of everything that is solidly fixed to the breech and barrel because we can reasonably assume the modulus of elasticity and rigidity of those parts is high enough that deformation is negligible. Anything not solidly fixed along the same axis is a damper and will transform some of the energy into heat.

It is a good quality you have, then, to admit when you are wrong!

A real engineer would never say that a rifle bolted/welded/super glued onto a robot doesn't have any recoil benefits over one held in hand by a person.

[SQW]

Nightbird, on 11 March 2018 - 04:22 PM, said:

A real engineer would never say that a rifle bolted/welded/super glued onto a robot doesn't have any recoil benefits over one held in hand by a person.

Well, of course a normal bullet doesn't have the force to shift a multi-ton robot. A 120mm autocannon mounted on a high shoulder joint on the same man-shaped robot though...?

[Nightbird]

SQW, on 11 March 2018 - 04:36 PM, said:

Well, of course a normal bullet doesn't have the force to shift a multi-ton robot. A 120mm autocannon mounted on a high shoulder joint on the same man-shaped robot though...?

Just talking about the same rifle firing a 5.56 NATO 45 round. Any difference between one held by a person versus one bolted on a man-shaped robot? (suppose both are 200 lbs)

[MW Waldorf Statler]

Necromonger Commander, on 11 March 2018 - 03:39 PM, said:

They are leaving lights too small to make them playable. Remember in table top a light cannot beat an assault, ever.

in TT a pilot can not aim a shutdown mech ...Miss Hits by a 60kmh slow 12 m Tall warmachine in 300m (thats firing Ranges of the American Civil War against humans with 1,8 m and hit of the Other Side Aerospacefighters with 300kmh
) and in TT lights good against Infantry ..light vehicles ...what for doing Lights in MWO ???? she with this useless.

So many in the TT very abstract and unrealistic in each Sense.

Edited by Old MW4 Ranger, 11 March 2018 - 08:55 PM.

[MW Waldorf Statler]

By this Hollander ...the Artist forget the Place for Ammunition

we're talking about Volumetric Volumes and Recoil on Mechs, where not even a ton of ammo would have room, considering the size of the caliber and missile systems, which then magically move from left hand and left foot into the Right Shoulder Launcher
...

the artistic point is the only one in terms of size.
What we think is appropriate, because only after this point, the 'Mechs were designed or what we feel as good in relation to the other weapons systems .. We can of course also scale the tanks larger .. yes wear the same weapons and need the same place for ammo ... why should then a 60t tank suddenly just look like a dwarf against a Shadowhawk...a Vedette Tank has now a AC5 thats against the Shadowhawk AC5 is only sized like a MG..




who the Hell is the Place for all this ?



or this Pic from a Artist here in Forum...the Maingun of the Tank only a Toy against the MWO Mech AC (middle Shadowhawk in old Lore Size)

Edited by Old MW4 Ranger, 11 March 2018 - 09:03 PM.

[Nightbird]

Old MW4 Ranger, on 11 March 2018 - 08:56 PM, said:

or this Pic from a Artist here in Forum...the Maingun of the Tank only a Toy against the MWO Mech AC (middle Shadowhawk in old Lore Size)

That tank to lore size shadow hawk size looks pretty good actually. A staple like the M1 Abrams is 60-70 tons, and looks to be about the same volume as the middle lore shadow hawk. That's not much of a decrease in density and can be attributed to futuristic armor and structure. That MWO size though... foam, feathers, and balloons are needed for that size at 50 tons... LOL

[MW Waldorf Statler]

im can carry in a Catapult per Ton 24 MLRM missles .who the Place for it by 10 t ? thats 240 Missles with loadingmechanism? the complete Slotsystem and Mechlab is nonsense and works with Fantasy Objects thats have not Size...1 T of Missles the same size as a Heatsink??? with loading Mechanism ??

the models have nothing to do with the Construction rules ...we could take spheres or cubes instead of the models and they would at least be uniform in shape ... while the 'Mechsmodels' shape does not follow any rules and does not follow any rule

Edited by Old MW4 Ranger, 12 March 2018 - 03:07 AM.