73 replies to this topic

[TB Freelancer]

All I read was the forum title but;

What about real shake. In MW4 getting hit by LBX20 would twist a mech damned near around the other way, not jiggle the screen and do zero to the cross hairs like now, you know, the placebo shake.

What about knockdown where smacking a gnat with LBX20 would send it skidding on the ground for 20 meters?

What about a proper heat system?

What about rearview cameras?

What about being able to look left and fire with your left arm (or right) as you drive by a an enemy mech in a mech with arms.

What about ECM. (that's hundreds of threads in of itself)

meh...I could go on with a few dozen items. Mostly stuff done right over a decade ago...

...I guess its lostech. Its all just lostech.

Edited by TB Freelancer, 29 July 2014 - 02:49 PM.

[Strum Wealh]

Elyam, on 29 July 2014 - 12:52 PM, said:

Hats off to you for all the quotes. I'm a huge fan of the fiction and all resource book commentary (though of earlier books). Of course, the color commentary of the stories has always included such descriptions, but in actual TT gameplay did not exist (no rule of any kind for recoil) because it was assumed to stabilize between the 10-second rounds. Now, the heavy gauss came later than my time - I've never worked in any period later than 3058, so please forgive me that construction rule oversight. For all I know more might have been added in even later years.

As I said above though, It would be interesting to have some effects, especially visual, but taking into consideration the idea that it has never been a part of BT play, and as such, should not be added as powerful, immense, or with heavy implications for the gunner. MWO can stretch a bit in this area if it wants to.

Recall, though, that the basic TT gameplay rules are intentionally designed as an abstraction of the lore, purposefully simplified so as to ensure that a TT round can be played out in reasonable time & space constraints, as well as to enhance TT gameplay aesthetics.

• "However, players should note that such 'real world' terms are abstractions when applied to the board game. Classic BattleTech is a game, not a detailed simulation. Therefore, the real world must take a back seat to game play - for simplicity, length of play, space required and simple enjoyment." - Total Warfare, pg. 36
  
• "Finally, the abstractions of real-world factors such as firing distance often can enhance the aesthetic of the game universe. Classic BattleTech has always been about 'in-your-face' combat, which works best with closer ranges. Players are encouraged to remember such abstractions and not get bogged down in real world mechanics and physics. Just enjoy the game!" - Total Warfare, pg. 36

In this case, a MechWarrior's ability to deal with the recoil produced by his/her 'Mech's weapons would be abstracted into the Gunnery skill ("Gunnery Skill helps determine how easy or difficult it is for the warrior to make a successful shot using his unit’s weapons." - Total Warfare, pg. 39), where a "better" Gunnery score represents, among other things, a greater ability to account for & mitigate the effects of the weapons' recoil.
Thus, why Kai Allard-Liao or Natasha Kerensky (both of whom are Gunnery 0 (and Piloting 0) MechWarriors - source) can sit in a given 'Mech and hit virtually anything that crosses their path, while an "average" Mechwarrior (Gunnery 4 for an average IS MechWarrior, Gunnery 3 for an average Clan MechWarrior - Total Warfare, pg. 40) can sit in exactly the same 'Mech in exactly the same scenario and be shooting at exactly the same target & be far less likely to hit the target in question.

As for the Heavy Gauss Rifle, the specific rule regarding the PSR needed to keep the 'Mech upright is found on page 136 of Total Warfare.

Quote

A ’Mech expending any MP and firing a heavy Gauss rifle in the same turn requires the attacker to make a Piloting Skill Roll at the end of the Weapon Attack Phase, with the following modifiers based on the unit’s weight class: Assault –1, Heavy 0, Medium +1 and Light +2. Unlike other Piloting Skill Roll effects, this is not cumulative; if the same unit fires two heavy gauss rifles in the same turn, two rolls would be required, but only the single modifier would apply to each roll. Other standard modifiers (such as 20+ points of damage inflicted in the Weapon Attack Phase, damage to actuators and gyros and so on) apply to the Piloting Skill Roll as usual.

For example, if an undamaged FNR-5 Fafnir with an average IS MechWarrior (Piloting 5, Gunnery 4) at its helm were to fire both of its HGRs in the same turn in which it had moved (expended MP) adross level & uncluttered terrain (e.g. no modifiers), the player would roll twice (once for each HGR) with a target number of 4 (Piloting 5, plus the -1 modifier for the Fafnir's being an Assault 'Mech). By contrast, an undamaged BZK-F7 Hollander in exactly the same scenario would have a target number of 7 (Piloting 5, plus the +1 modifier for the BZK-F7's being a Medium 'Mech) - the lighter 'Mechs cannot handle the extreme recoil as well as the heaver 'Mechs (attributable to conservation of momentum, strength of actuators, and so on).

Edited by Strum Wealh, 29 July 2014 - 03:47 PM.

[Joseph Mallan]

Sturm Unless they added something since I left, the -1 is for Piloting roll not to hit.

[CocoaJin]

For awhile, I was willing to accept that recoil was effectively dealt with as an integral part of chassis design, but the I ran across this excerpt for a Scorpion quadruped mech.

"The 'Mech was originally intended as a stable weapons platform but as the model came into service it was relegated to an infantry support role."...."If the design is looked at through an objective standpoint, the Scorpion is a very capable 'Mech at its intended role. With the PPC mounted in the body and with the inherent stability of the design, the 'Mech is a very stable platform for long-range fire."

http://www.sarna.net...ion_(BattleMech)


This suggest that recoil is an issue for mechs, especially with respect to our bipedal chassis. With this new found info, I'm much more willing to endorse its inclusion in game.

I'd also accept the use of cross hair wobble due to mech movement...the portion of the excerpt i excluded spoke about pilots disliking the quad's rough gait...I assume that would be an issue for aiming.

Edited by CocoaJin, 29 July 2014 - 04:53 PM.

[Strum Wealh]

Joseph Mallan, on 29 July 2014 - 04:42 PM, said:

Sturm Unless they added something since I left, the -1 is for Piloting roll not to hit.

And I did indicate that the rule was "...regarding the PSR needed to keep the 'Mech upright..." as a result of the effects of recoil on the 'Mech. The rule itself indicates that Assault 'Mechs receive a bonus (the -1 modifier) to the PSR, while Medium & Light 'Mechs receive a penalty to the same PSR (+1 and +2 modifiers, respectively). So, staying upright after having fired the shot falls under the purview of the Piloting skill and the PSR.

By contrast, abstraction of the ability to account for recoil with regard to actually making (or attempting to make) the shot connect with the target - e.g. the MechWarrior's ability to account for the weapons' recoil through their own ability to aim said weapons - would, much like leading a moving target (which does have its own Target Movement modifier, on page 108 of Total Warfare), logically fall under the Gunnery skill & the to-hit roll, yes?

[Y E O N N E]

POOTYTANGASAUR, on 29 July 2014 - 08:52 AM, said:

I'm sorry, but there really isn't a way that I can correct you without insulting your intelligence. A gauss rifle or rail gun works by using electromagnets set in an extremely precise sequence to accelerate a metal shells exponentially before exiting the barrel. This process produces zero recoil as their is no force being exerted on the shell or the mech, other than the push/pull of the magnets. The magnets do all the work accelerating the shell instead of an expansion of gasses like most other firing mechanisms..... Which DOES cause recoil, especially on large shells like that of an ac20 which require much larger gas expansion for similar firing results to smaller shells.

TL;DR
Ur wrong bro.

The only intelligence you risk insulting is your own.

Those same electromagnetic forces that are pushing the projectile forward are also trying to push the gun back. In the case of a rail gun, they are also trying to send said rails flying away from each other in opposite directions.

What you are proposing is called "reactionless" and, thus far according to what we know about physics, impossible (or super improbable, going with quantum theory and all that jazz)..

[POOTYTANGASAUR]

Elyam, on 29 July 2014 - 10:19 AM, said:

In BT all recoil is compensated for through a variety of methods. It has no effect on play, especially since it lives within a 10-second impulse. But as with many other things, MWO allows some greater simulation prospects. We should keep with the general low to no effect of recoil, but visually we should see both the recoil force and the compensation mechanisms and experience some of those as long as they stabilize somewhat quickly. It would be more of a cosmetic effect, but some actual effects wouldn't be bad if carefully implemented.

We have no true functioning rail guns or gauss rifles. Definitely not nearly as advanced as in BT. I have seen and have fired a small "rail gun", it used small electromagnets to fire 1/8" ball bearings. It could fire at about ~200 fps. It had literally no recoil, it had a slight lag between pressing trigger/button and actual mechanism working. But there was no recoil. It was quite a cool gun albeit being attached to an array of batteries with only a few feet of slack, still fun toy.


We (scientists, not actually me)are experimenting with this type of weapon technology but don't have any full sized (meaning mech scale) weapons to test. Nor anything much larger than what I fired..... Sadly.

[Y E O N N E]

Spoiler: the weapons technology in Battletech is actually easily built using 21st century know-how.

We have real, working rail-guns. Naval-grade, actually. We've also got lasers, though not as compact as the BT ones. Our real-world missiles and cannons are far superior to anything in BT, however. We've also got better computers.

As for the EM-propelled rifles, people have built small versions of both rail- and coil-guns in their own homes, as you have no doubt seen. The reason there is seemingly no recoil is because the rounds are either so un-massive or being propelled to such low velocities (read: there is very little kinetic energy involved) that it's not enough to budge the device or the person.

Ever fire a .22 LR rifle? They feel like they have no recoil at all, but they do. Firing the same round from a pistol kicks the gun noticeably because the gun is much lighter and the moment arm is longer.

[CocoaJin]

We discussed gauss/rail gun recoil years ago. From academic paper read( I think it was from the University of Texas) it suggested recoil does in fact exist...but it can be theoretically directed in whatever direction is desired based on the shape of "barrel". It suggested the use of 90 deg bends in the barrel as the simplest method...but it had the problem of having the projectile damage the wall of the barrel as it turns the corner.

I wish I remembered how the recoil was directed relative to the projectile's flight path from a standard straight barrel. I do remember that the barrel wants to expand apart, but the recoil is there. Oh snap, I remember!!! Recoil is directed in what ever direction the butt if the barrel is facing...so if you bend the butt of the barrel downward, it will direct the recoil toward the ground, even if the round is fired forward.

Now I'm not certain if the round has to make the turn, or if it can be loaded in the breech after the bend or not.

So assuming a straight barrel and recoil being directed out of the rear of the weapon, we still have to consider how that force creates moments around joints for arm mounted guns, and with respect to the CoG of the mech for all mounts.

[Y E O N N E]

You mean this paper?

It's actually not that simple. The paper is considering the the forces trying to send the rails flying as part of the recoil, which is technically right. It's also primarily dealing with how to feed the weapon, and it shows that the projectile won't move using certain geometries because the forces aren't summing up in the desired direction.

What we're concerned with is the action/reaction created by shoving a projectile out the barrel. In this case, that's always along the same axis as bore. Raising the bore higher on your firing platform merely creates a longer moment arm or, in layman's terms, a less stable firing position. See Figure 10 in the above link.

[Training Instructor]

Heffay, on 29 July 2014 - 08:36 AM, said:

Do you have any idea what you're talking about, or is your physics education based on "this is how I imagine the world working"?

Yeah, I've actually seen them doing strafing runs from less than 1.5 kilometers away, and I was watching them from the side. Firing the gun visibly and dramatically slows down the aircraft. They weren't firing blanks at some air show. They were firing live ammo on a training range. Unless all of those cluster bombs they were dropping were full of confetti and candy.

Maybe you pedantic pogues can come up with the physics equations for how my eyes weren't working during the 45 minutes that 4 different A-10s spent doing target practice in Ft. Greely, Alaska?

[CocoaJin]

Yeonne Greene, on 29 July 2014 - 09:27 PM, said:

You mean this paper?

It's actually not that simple. The paper is considering the the forces trying to send the rails flying as part of the recoil, which is technically right. It's also primarily dealing with how to feed the weapon, and it shows that the projectile won't move using certain geometries because the forces aren't summing up in the desired direction.

What we're concerned with is the action/reaction created by shoving a projectile out the barrel. In this case, that's always along the same axis as bore. Raising the bore higher on your firing platform merely creates a longer moment arm or, in layman's terms, a less stable firing position. See Figure 10 in the above link.

Yeah thats it. Though I'm not sure the recoil will be due to a action/reaction of the round leaving the barrel or due to the breech(circuit closure)/butt of the barrel as described in fig.4-8, or both. But I think the paper does a good job of suggesting that recoil is or should in fact be present during the firing of gauss rifles.

And if recoil should be present, it should also be accounted and adjusted for in game play....it's one of the natural ways of balancing such effective weapons. We have to keep the players honest and not provide too easy a weapon/system that is so effective, yet so vanilla in its application that it becomes an exploit.

Honestly, they should have never gave us the infantry equivalent of a .50 cal sniper rifle, but with the ease of use of a pistol. High lethality coupled with simple ease of use us is begging for exploitation, excessive use and difficulty in balancing. Recoil could have been an early mechanic for naturally balancing the Gauss, PPC, AC20....and to some lesser extent, the AC2 and UAC5.

Now I'm not saying we need to see the weapons have walk up when fired, just cross hair wobble/bounce and some dispersion when followed up or fired with other weapons.

[LordKnightFandragon]

There should totally be Recoil for all weapons...

[Y E O N N E]

The paper actually only deals with railguns, which are very different in operation to Gauss rifles (also known as coilguns). The easy way to explain the operation of a rail-gun is that the currents running through the rails generate magnetic fields opposite each other, and because the rails can't move, the only release valve is moving the projectile(the "armature" referred to in the paper) along their length. What the paper talks about is how certain configurations (those right-angle ones) won't work because they provide an alternative path for the current to flow, a path that results in no movement from the armature.

But yes, recoil is present in both types of firearms. It's really not any more complicated than Newton's Law's of Motion; the method of propulsion is irrelevant, just know that it is always reactionary in nature.

Thus, there should be recoil for them in the game. Actually, I think it would be fun as hell to play with recoil mechanics. Think of the pitched firefights and that frantic race to get yourself re-aligned for the shot! Or think of a co-ordinated effort to have everybody fire at one target in such a way that the recoil will line them up with the next! That's some awesome stuff.

[CocoaJin]

Training Instructor, on 29 July 2014 - 10:39 PM, said:

Yeah, I've actually seen them doing strafing runs from less than 1.5 kilometers away, and I was watching them from the side. Firing the gun visibly and dramatically slows down the aircraft. They weren't firing blanks at some air show. They were firing live ammo on a training range. Unless all of those cluster bombs they were dropping were full of confetti and candy.

Maybe you pedantic pogues can come up with the physics equations for how my eyes weren't working during the 45 minutes that 4 different A-10s spent doing target practice in Ft. Greely, Alaska?

I've heard anecdotal statements suggesting the A-10 slows down while firing its gun, and honestly, I don't doubt it. But I think its a bit of a stretch to say it'll eventually go backwards before spiraling out of control. It'll no doubt slow the aircraft enough to cause it to stall, but I can't imagine it could make the plane go backwards first. Now, once it stalls, if the pilot kept firing, it might off set the natural tendency of the plane's nose to drop, instead letting the tail drop and the the tail first descent eventually resulting in a spin or some other horrible lack of control, including a spiraling flopping mess. But I cant imagine the gun as enough recoil to ignore the aerodynamic forces inherent in the plane to over power them even briefly to allow for a short period of reverse flight. The A-10 is going to stall well before it gets close to even stopping, at which point it'll just flop with increased lose of airspeed due to the gun firing.

That being said, I could be wrong...though I'd like to hope my instincts as a Commercial/ATP pilot would be correct on the matter...not that we get the chance to fly backwards much.

[Heeden]

@Strum

I thought in Battletech the pilot's aiming skills were pretty much a non-factor as the in-lore Battlemechs use targeting computers and aim their weapons automatically, with the pilot mostly deciding when to fire as the on-board systems work out where to fire.

[MeiSooHaityu]

MonkeyCheese, on 29 July 2014 - 12:23 AM, said:

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...

Yep, the larger weapons that would have recoil would also be able to recenter before the next shot was ready. It wouldn't really accomplish anything.

Just think that the mech's gyros stabilize the mech when the shot is fired . Its the same black magic that moves ammo from the legs to the weapons

[MeiSooHaityu]

P.s. I also heard the A-10 slows down when firing it's auto cannon. That is why it fires in bursts instead of one continuous stream. It is also why the barrel is centered in the plane (so as not to pull the aircraft to one side when firing). If the pilot fired a continuous stream while the plane was in a low speed straffe run, it could stall the plane and crash it. That is why it burst fires. I am pretty sure that is the reality of that gun platform.

[9erRed]

Greetings all,

Heeden, you are correct, in that the optics are not directly linked to any of the weapons themselves.

- thus any 'recoil' would never be 'seen' from the Pilots reticle.

Everything related to the Pilots 'Reticle' and maintaining a rock solid aim point is processed through a couple of systems found on all Mech platforms. Some better than others (advanced) but they all send there sensor information from the physical weapons through the Diagnostic Interpretation Computer (Di) systems to the Battle Computer (BC) and Targeting &Tracking computers, collimating in the Pilots HUD or neurohelmet.

~ The Battle Computer (BC), located in the cockpit, coordinates and monitors the overall movement and weapons fire. It is the BC that makes sure that the MechWarrior's commands have priority. The BC makes certain that weapons are pointed towards what the MechWarrior is indicating, even if that requires overriding other systems and warnings and putting an arm through the wall of a nearby building. It is the BC that does the computing for "Targeting and Tracking."

~ The BC is the "gateway" that filters the data from the DI computer, converting it to information that is useful for the MechWarrior so the MechWarrior does not need to interpret it. It also coordinates all of the weapons Targeting and Tracking (T&T) systems, feeding them and the MechWarrior data on internal checks that the DI computer has run. The BC also controls the Target Interlock Circuits (TIC) of the 'Mech.

~ the Diagnostic Interpretation computer also compensates for the recoil of the BattleMech's autocannons and other recoil generating weapons, in both instances in order to try and maintain the 'Mech's balance. However, it is the MechWarrior's sense of balance, as translated by the Neurohelmet, that handles what the balance sensors and Diagnostic Interpretation computer (Di) cannot cope with or predict for.

Everything that is 'represented' in the Reticle is compensated, recoil would not even be seen, as the Pilot would only have indications of when the weapons are ready to fire again.
- But does this mean that recoil has not effect on the Mech's operation, No.
- Again all that force is handled through the Mech's computer systems, gyro, and BC. (in this verse)

Should we see any form of 'Recoil' from with-in the game, probably not. But there are many examples of 'BattleTech novel' authors over emphasizing these effects 'for story enhancement'. With or with out any 'real world knowledge' on how these devices were stated to operate, or 'at the time/current' physics state these designs 'should' operate.
- There is/was other 'options' for some of these Mech chassis to compensate for what the Lore states was massive recoil from some of the weapons. Leaning into a shot, kneeling down to steady the Mech for high placed weapons, (Jaeger, Uziel, as examples).


Side note of the A-10 gun:
- A 70 round burst of 0.4 kg shells fired at 1000 m/s corresponds to a speed reduction of a 15 ton aircraft of 0.2 m/s, which is less than half a knot. The weapon is the 30 mm GAU-8/A Avenger Gatling-type cannon, and is off set in the aircrafts frame so that the single firing barrel of the 7 barrels is in line with the aircrafts center line.

Just some notes,
9erRed

Edited by 9erRed, 30 July 2014 - 04:55 AM.

[Strum Wealh]

Heeden, on 30 July 2014 - 02:20 AM, said:

@Strum

I thought in Battletech the pilot's aiming skills were pretty much a non-factor as the in-lore Battlemechs use targeting computers and aim their weapons automatically, with the pilot mostly deciding when to fire as the on-board systems work out where to fire.

It's actually quite the opposite - the MechWarrior's gunnery skills (represented in TT by the Gunnery Skill Rating) is the primary factor in determining whether the 'Mech can actually hit a given target under a given set of conditions.

• "A unit’s base to-hit number is equal to its Gunnery Skill Rating. When modified for range, terrain and other factors, this number becomes the modified to-hit number." - Total Warfare, pg. 40
  
• "The base to-hit number for a weapon attack is equal to the firing unit’s Gunnery Skill Rating" - Total Warfare, pg. 106

There are a number of modifiers that act to produce the modified to-hit number, including:

• Range Modifier ("The farther away the target is from the firing unit, the more difficult it is to hit." - Total Warfare, pg. 106)
  
• Minimum Range Modifier ("Some weapons, such as particle projector cannons, autocannons and long-range missiles (LRMs), are designed to be fired at long-range targets. Close-range, targets are more difficult to hit." - Total Warfare, pg. 107)
  
• Attacker Movement Modifier ("A moving attacker must constantly adjust his aim to compensate for his movement, so an attacking unit’s to-hit number is modified by its own movement..." - Total Warfare, pg. 108)
  
• Target Movement Modifier ("A moving target is harder to hit, and so an attacking unit’s to-hit number is modified by its target’s movement..." - Total Warfare, pg. 108)
  
• Terrain Modifiers ("Terrain can affect the probability of a successful shot by forcing the attacker to account for intervening land features and partial cover." - Total Warfare, pg. 108)
  
• Multiple Targets Modifier ("A player may declare that his unit will engage more than one target in a turn and allocate different weapon systems to fire at different targets." - Total Warfare, pg. 109)
  
• Heat & Damage Modifiers ("The attacking ’Mech may need to modify its base to-hit number for current combat damage and heat build-up." - Total Warfare, pg. 110)

Nearly of these modifiers represent aspects of combat that are to be overcome by pilot skill (as all of them are applied to/against the MechWarrior's Gunnery skill rating, rather than any rating inherent to the BattleMech itself) - it is the MechWarrior, not the BattleMech itself, that must lead the target & account for relative movement (Attacker & Target movement Modifiers); it is the MechWarrior, not the BattleMech itself, that must aim carefully enough to hit an exposed component of an otherwise-concealed opponent (Terrain Modifier); it is the MechWarrior, not the BattleMech itself, that must account & adjust for any sluggishness/unresponsiveness due to the 'Mech's being overheated or damaged (Heat & Damage modifiers).

This is why one can take three precisely-identical 'Mechs - identical right down to the nuts & bolts - and place three "slightly" different pilots in them (one average IS MechWarrior (Gunnery 4), one above-average IS MechWarrior or average Clan MechWarrior (Gunnery 3), and one below-average MechWarrior (Gunnery 5)) and see substantially different results:

• The average IS MechWarrior, with no modifiers applied, will have a to-hit number of 4 against a 2D6 roll; on a result of 4 or up, the target is hit, while a result of 3 or below indicates that the shot missed.
  
• The above-average IS MechWarrior & average Clan Mechwarrior, with no modifiers applied, will have a to-hit number of 3 against a 2D6 roll; on a result of 3 or up, the target is hit, while a result of 2 indicates that the shot missed.
  
• The below-average IS MechWarrior, with no modifiers applied, will have a to-hit number of 5 against a 2D6 roll; on a result of 5 or up, the target is hit, while a result of 4 or below indicates that the shot missed.

With 2D6 probabilities, we can determine the following:

• The average IS Mechwarrior (Gunnery 4) has a base accuracy of 91.6% with most weapons (e.g. those that do not have a built-in modifier for the weapon itself).
  
• The above-average IS MechWarrior & average Clan Mechwarrior (Gunnery 3) have a base accuracy of 97.2% with most weapons.
  
• The below-average MechWarrior (Gunnery 5) has a base accuracy of 83.3% with most weapons.

Even identical 'Mechs with "slightly" different pilots - or the same 'Mech, with different pilots rotating in & out - can see significant differences in performance & combat effectiveness as a result of even minor differences in the pilots' skill level.

BattleMechs are NOT the "the machine does everything for you" vehicles that some try to make them out to be; if they were, even large differences in pilot skill would have relatively small, if not negligable, differences in the 'Mech's combat effectiveness.
While they do have systems in place to aid the Mechwarrior and improve their combat effectiveness, it is ultmately the MechWarrior himself/herself that is the primary determining factor in the 'Mech's performance, and the demonstratable differences in 'Mech performance reflected in the differences in pilot skill illustrate this.