73 replies to this topic

[Killian De Morte]

One element that seems to be missing is recoil ?

Surely a massive AC20 cannon or Gauss rifle should throw the aiming crosshair up and randomly left or right big time when shot ?

I know these are big gun platforms - but in real-life do you ever see even a small artillery piece fire a shell with zero recoil ?

It could be added to make big / multi ballistics a bit more unique compared to lasers and PPCs
I know the slow moving shells require skill to lead a target etc - but with no "kickback" you may as well be using a peashooter or air-rifle, its about the 'feel' of it.

OK so zero recoil for machine guns - but surely anything over an AC2 should jump the aim point about a bit after firing - It would not effect the initial hit - but the pilot would need to pull the aim back in for that second AC10 or AC20 shot !

[Draykin]

PPCs canonly do have recoil. However, I believe most people will assume that a 'Mech is a mostly stable firing platform, and has systems installed to compensate for recoil.

Also, given the rate of fire for higher bore ACs, would it really matter to have recoil if you have 4 seconds between shots?

[Training Instructor]

They can't even manage night optics that are up to 2014 standards, let alone 3050 standards. Do you really think the mechs have some great recoil compensation systems?

Recoil has been suggested before,and it would be nice to do something about the boomJagers and boomCats.

[ProtoformX]

Training Instructor, on 29 July 2014 - 12:11 AM, said:

They can't even manage night optics that are up to 2014 standards, let alone 3050 standards. Do you really think the mechs have some great recoil compensation systems?

Recoil has been suggested before,and it would be nice to do something about the boomJagers and boomCats.

A 'Mech killed me. Quick, the nerf bat.

Edited by ProtoformX, 29 July 2014 - 12:13 AM.

[MonkeyCheese]

Killian De Morte, on 28 July 2014 - 11:33 PM, said:

Surely a massive AC20 cannon or Gauss rifle should throw the aiming crosshair up and randomly left or right big time when shot ?

You mean like recoil patterns in modern day FPS games? would be pointless as you could just readjust your aim during that slow reload time of an AC20 or Gauss, and having a recoil longer than that slow reload time would just be business suicide...

[Hans Von Lohman]

I think they mentioned recoil, and it turns out that there is more to it than you would think.

One of the big ones was that they're staying away from random shots. If you play most shooters, your gun's accuracy goes down and you fire bullets in an ever widening cone. From what was said on the NGNG podcast 115 with Russ Bullock as a guest MWO doesn't do well with netcode and randome shots.

Why? Well, to prevent cheating your shot would have to be sent to the server for it to be verified that it scattered correctly, and the results sent back to you for your graphics to update and show the shot. That sort of thing loads down MWO a bit too much, so they don't do it.

If you want that sort of randomness done client side, well then hackers can just make a mod so your shots always land center of the crosshair every time.

Don't quote me on that, but I believe this is what they were talking about.

[PhoenixFire55]

The heaviest slug of them all is the AC20. It weights approx 1/7 of a ton or ~0.14 tons. AC20 projectile speed is 650m/s. The impulse given to the AC20 slug equals the impulse given to the mech firing it (provided the weapon isn't moving relatively to the mech). So we have m₁*v₁ = m₂*v₂. For the lightest mech with an AC20 (lets say BlackJack), which has the mass of 45 tons, the speed it'll acquire due to recoil is v2 = v1*m1/m2 ~ 2m/s. Aka, the BJ will fly 2 meters back. That is provided the mech is motionless in the air.

Now if a mech already has some forward momentum, for example moving at 80kph or ~ 21m/s, it'll experience a slight momentary drop off in movement speed. If we also take into account that mech actually stands on the ground and thus have some sort of friction between its legs and the surface this effect will be even less.

However, the BattleTech tech manuals state, that a mech is designed in a way, that it effectively compensates all recoil from weapons it fires as well as all impacts from enemy weapons using the internal gyros and myometers much like a human would use his muscles to compensate recoil from firing a gun or absorb a punch.

Judge this info however you like, but from my point of view, yes, there should be slight recoil that lasts for about 0.5 seconds needed for your mech systems to adjust and compensate. However, there are no weapons (except for MGs) that fire faster than 0.5 seconds, thus this recoil will in no way affect your next shot, and as I've shown the effect on the movement speed of the mech is also negligible, or at least small enough for devs not to bother.

Situation when an AC20 is fired from an arm is mostly same. Arm weights far less than an entire mech, but an AC20 mounted there takes the entire arm space meaning you have no other weapons in it. Thus all the recoil from the shot will be well compensated at the time when an AC20 is ready for the next shot. This recoil will in no way affect other parts of the mech and weapons in them or the position of your crosshair.

As for the Gauss Rifle ... its a magnetically accelerated piece of metal. Such weapon generates no recoil whatsoever.

[Y E O N N E]

Draykin, on 28 July 2014 - 11:39 PM, said:

PPCs canonly do have recoil. However, I believe most people will assume that a 'Mech is a mostly stable firing platform, and has systems installed to compensate for recoil.

Also, given the rate of fire for higher bore ACs, would it really matter to have recoil if you have 4 seconds between shots?

Funny thing about BattleTech 'Mechs: until you get to Heavies they are generally lighter than a modern-day Main Battle Tank. A current Abrams M1A2 is actually 68 tons.

Now, the AC/20: assuming it's firing the max-size 203 mm round, then that's a ~8-inch shell. That is Cruiser-grade weaponry. Using that on land requires elaborate setups generally involving building the weapon on-site and/or using railroad cars.

tl;dr: BattleMechs are magic.

Addendum: Railguns and Gauss rifles do generate recoil. If the device weren't both more massive and/or bolted down, then it would go flying back while the round remains stationary.

Physics, man, physics.

Edited by Yeonne Greene, 29 July 2014 - 12:55 AM.

[R Razor]

When a mech is struck by an AC20 round you can see said mech recoil from the shock of the impact, so it would make sense that firing such a large caliber weapon would generate some kind of recoil that would affect the mech doing the firing as well. At least in the case of an IS AC20, burst fire should behave a little different I would think.

I sometimes wonder if the issue is a matter of incompetence on the part of the developer or a limitation of the engine the game was built on.

[FlipOver]

Recoil should be added to this game. The smaller (lighter) the 'mech, the higher the recoil.

But that's not the only thing missing. What amazes me the most is this:

You fire an AC20 to an Atlas torso and that 100 TON 'mech's torso gets moved back by the impact.
But then you fire the same round into any other 'mech (90% of them are lighter) and NONE of them budges. It's like the Atlas is trying (and failing every single time) to make the Matrix move against AC20 fire.

[Training Instructor]

If you've ever seen an A-10 do a strafing run with the cannon, they can only fire short bursts because the recoil from the gun is like slamming on the brakes in mid-air. If they just held down the trigger, the plane would stop and begin going backwards for a brief time before it spun out of control.

Most of the mechs have a relatively high center of gravity. The Jager and Blackjacks, for example, mount their AC20 very high up, which dramatically increases the force of the recoil through simple laws of physics. The further you are away from the pivot point, in this case the ground, the more force is exerted. At Atlas or Orion, by contrast, mount their AC20 quite low, requiring less recoil compensation.

Gauss rifles should have no recoil, but should create far more heat. Autocannons use an explosion to propel their payload, but gauss uses electromagnets powered by capacitors to accelerate a projectile. Those capacitors generate a lot of heat when they charge up and unleash all that energy.

[AlexEss]

it is 1980´s sci-fi magic.... But if you really need to have a working solution...


Just imagine that the guns are made from a very strong and light material and that the most of the weight is take up by a advanced recoil absorbing system.

After all if real science would be taken in to account i am pretty sure stepping on to hard packed snow or a lake bed would be a very bad idea seeing how small feet some mech have... But i might be wrong.. i am sure someone who did not flunk advanced math will correct me.

[Bartholomew bartholomew]

It would look cool. Of course there is more than enough cool down time that it would come back on target. However, well...

You have to stop and honestly consider, would they get it right?

Also it was in the mechwarrior 5 trailer they made. So they had thought about it.

Which brings the thoughts of minimally viable product to mind..

[PANZERKAT]

Yeonne Greene, on 29 July 2014 - 12:52 AM, said:

Funny thing about BattleTech 'Mechs: until you get to Heavies they are generally lighter than a modern-day Main Battle Tank. A current Abrams M1A2 is actually 68 tons.

Now, the AC/20: assuming it's firing the max-size 203 mm round, then that's a ~8-inch shell. That is Cruiser-grade weaponry. Using that on land requires elaborate setups generally involving building the weapon on-site and/or using railroad cars.

tl;dr: BattleMechs are magic.

Addendum: Railguns and Gauss rifles do generate recoil. If the device weren't both more massive and/or bolted down, then it would go flying back while the round remains stationary.

Physics, man, physics.

When people think recoil, they vision a canon going back and then forward. Physics be damned! If canon barrel no move, no recoil!

[Killian De Morte]

Back to my comment :

but with no "kickback" you may as well be using a peashooter or air-rifle, its about the 'feel' of it.

Lasers are high energy beams of light - no-one says they need to be pink/green/blue or yellow but having invisible spears of energy just wouldnt 'feel' right would it ?

The cool down between shots would mean that "yes" you could re-focus your aim in plenty of time, but it would feel right.

I love to drive around a Guass-Raven for fun when not running bigger mechs - How cool would it be that when this little mech pops off a giant metal slug the sights jump-up and he skids back 10 feet - LOL

Also there is a lot of talk about AC5 poptarts - watch them fly uncontrolably backwards when shooting in mid air or how about spinning wildly if not shooting an AC5 from both arms/torsos in mid air

Edited by Killian De Morte, 29 July 2014 - 04:47 AM.

[Mechteric]

I wouldn't be opposed to recoil if it might help the immersion, but recoil won't affect large ballistics because recoil only affects subsequent shots and right now autocannons have lots of time between shots, so this would pretty much encourage alpha strikes more, not less.

Now if all autocannons were changed to fire as quickly as AC2's perhaps there could be a use there as they would become DPS weapons instead of Front Loaded Damage weapons. (strictly speaking about IS AC's here)

Edited by CapperDeluxe, 29 July 2014 - 05:23 AM.

[MAXrobo]

To the people saying that it would not mater because of long cooldown times. While it wouldn't change anything for firing just one gun, you need to remember that battlemechs have many weapons that all act differently. Adding in recoil would actually help prevent alpha striking to some extent. You could not effectively fire lasers at the same time as projectile weapons because you would only get to keep the beam on target for a second before it got knocked away by recoil.

Also, it would just be really cool to see your mech jerk back a bit when firing big weapons. It would just give them a little more impact and feeling than the glowing potatoes we are throwing at each other right now.

Edited by MAXrobo, 29 July 2014 - 06:08 AM.

[Mechteric]

MAXrobo, on 29 July 2014 - 06:06 AM, said:

Adding in recoil would actually help prevent alpha striking to some extent. You could not effectively fire lasers at the same time as projectile weapons because you would only get to keep the beam on target for a second before it got knocked away by recoil.

But most of the front loaded damage builds that are most often complained about use AC's, Gauss, and PPCs. Recoil won't affect them if they alpha those weapons.

[Strum Wealh]

Training Instructor, on 29 July 2014 - 02:43 AM, said:

If you've ever seen an A-10 do a strafing run with the cannon, they can only fire short bursts because the recoil from the gun is like slamming on the brakes in mid-air. If they just held down the trigger, the plane would stop and begin going backwards for a brief time before it spun out of control.

Most of the mechs have a relatively high center of gravity. The Jager and Blackjacks, for example, mount their AC20 very high up, which dramatically increases the force of the recoil through simple laws of physics. The further you are away from the pivot point, in this case the ground, the more force is exerted. At Atlas or Orion, by contrast, mount their AC20 quite low, requiring less recoil compensation.

Gauss rifles should have no recoil, but should create far more heat. Autocannons use an explosion to propel their payload, but gauss uses electromagnets powered by capacitors to accelerate a projectile. Those capacitors generate a lot of heat when they charge up and unleash all that energy.

No, to all of this.

First: the A-10 myth.
The A-10 (USAF factsheet HERE) is powered by two turbofan engines, each of which generate 9,065 pounds (40,323 newtons, or 40.3 kN) of thrust; together, the engines produce 18,130 pounds (80.6 kN) of thrust.
The GAU-8/A (General Dynamics Armament and Technical Product factsheet HERE) produces 10,000 pounds (44.5 kN) of recoil when fired.
The recoil from the gun IS NOT sufficient to overcome the thrust from both engines; the A-10 WILL NOT "stop and begin going backwards" if the gun is fired for an extended duration.

Second: gun mounting location & force vs moment
The gun would produce the same amount of recoil force regardless of where it is mounted on the 'Mech. The difference is in the distance - both vertically & horizontally - from the torso's center of rotation (e.g. the point where the upper torso attaches to the legs, about which the torso twists & pitches).
The difference between the Blackjack/JagerMech & the Atlas/Orion is that the former set mount the guns further away from the CoR. As a result, the moment (the multiplicative produce of the force of the gun's recoil and the distance from the center of rotation; see also: torque) is greater than for the latter set (where the guns are mounted much closer to the center of rotation).

Third: Gauss guns (coilguns) & recoil
Gauss Rifles (e.g. coilguns)propel their slugs by using an electromagnetic coil (or a series of such coils) to exert a force on the slug via a magnetic field. Likewise, the slug also exerts a force on the coil(s) through the same magnetic field.
Recoil compensation systems are even included as part of DARPA's coilgun mortar project.

• "The mount contains the recoil system and is capable of elevating the gun for future field demonstrations of projectile range capability."
  
• "The hardstand and baseframe are coupled to conserve the momentum of gun’s and catcher’s recoil."

In essence, coilguns (such as the Gauss Rifle) are just weaponized electromechanical solenoids, and their behaviors - including forces imparted on both the armature & the coils, which amount to "recoil" - are identical.


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KOMMISSAR KITTY, on 29 July 2014 - 03:45 AM, said:

When people think recoil, they vision a canon going back and then forward. Physics be damned! If canon barrel no move, no recoil!

First: "cannon" (with three "n") is the weapon, while "canon" (with two "n") is "is the material accepted as part of the story in an individual fictional universe" (which, in the case of BattleTech/MechWarrior, means the official novels/novellas/short-stories & TT rulebooks/sourcebooks).

Second: the back-and-forth barrel movement you're describing is a recoil compensation system - one notable specific example being the hydraulic recoil mechanism developed in the 1890s. It is also seen as part of several types of "recoil operation" system, to employ recoil as a means of helping to cycle the action of a firearm.

So, the reality of the situation is largely the opposite of your closing claim, where large firearms are concerned - if the barrel is moving along its own long axis, recoil is (generally) reduced.

[Training Instructor]

STrum, have you ever actually watched an A-10 scream down out of the sun on a strafing run, and then seen what happens to the aircraft when the cannon fires? A 1.5 second burst from the cannon is like watching the plane run into an invisible force field. No planes fly at max thrust in anything but an emergency situation, and most include governors that won't allow them to even try it in the first place. Also,the engines have to lift the plane and its payload, not just compensate for recoil.

Take a high-powered rifle. Brace it against your hip with one hand holding the barrel down. Pull the trigger. You'll feel the recoil, but the gun isn't going to move you unless you're skinny as a hipster barrista. Next,hold it normally, at shoulder level, in a normal firing stance and shoot again. The recoil is far more noticeable, because you are exercising the same force at a further distance from pivot, amplifying that force, and thus requiring more recoil compensation. As for the Jager and Blackjack vs the Atlas, the Blackjack's upper torso can only transfer so much of the force downwards before the mech has to take a step back in order to avoid falling over.

The Army liked the GAU-8 Avenger so much that they tried to mount it to various mobile land-based platforms, such as the M-113 personnel carrier. Testing discovered that the recoil from the gun was simply too much for any mount to handle. The A-10 uses forward speed and downward attack angle as a recoil compensation method. If they wanted to have the AC20 slow a mech down when it's fired, it would be pretty cool.

Edited by Training Instructor, 29 July 2014 - 07:53 AM.