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Author Topic: Emulating Deflective Armors Without BAR - Crit Chance version  (Read 907 times)

Daemion

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I've been putting brain-time in coming up with ways to emulate deflective armor in a way that can mesh with standard BattleTech.

The Big Idea

My current idea is simple enough.  Have the armor generate the target value for critical hit chance checks.

What do I mean?  Most BattleTech units that suffer critical hits only do so under specific conditions, and one of those conditions is rolling for a crit chance, whether on a table, like (currently) for BattleMechs, or having to meet or beat a target value, like for Aerospace and Vehicles to a different degree. 

The target value to get at least one crit for Mechs and Fighters is 8 or better.  I think it's 7 or better for the current vehicle ruleset.  (That wasn't always the case, but that's beside the point.)

Deflective Armor Concept: A location struck will check for critical hits, but the check is modified by the location's armor value.

There are two ways I can apply this.
The first is to apply the armor as a modifier to the crit check roll.
The second is to have the armor value be the target value, and style MOS off whatever chart is used. 

I'm going to work on the latter for now, as it's the easiest to make simple construction values for.  I'll also work on some examples in the form of MegaForce combat vehicles from the toy line by Kenner.  One of the biggest things is deciding on what kind of modifier to apply to armor tonnage to generate 'points' that can be assigned to the different locations.  That depends on if I'm going for modifier or target value.

TV requires some sort of modifier to be meaningful, but Modifier might not.  I really like 1.6, so far.  But, that can be variable based on unit cost.

(i) - I recognize that crits represent more than breaching armor, and that the target values also represent any back-up systems to counteract function losses.  This is a simplification of that abstraction.  However, it makes sense in its own way, to me, because deflective armor is usually about checking for penetration, and the severity of said penetration to make it simple.

The Reason
I want to be able to pit standard Mechs and BattleTech units against different combat units that perform differently.  (Basically, interuniverse cross-overs and in-universe historical battles that pre-date the Mech by a large margin.  :thumbsup: )

But?  BAR sucks.  It doesn't work the way it should, and it's current application doesn't reflect the historical performances suggested by certain weapons and BT's own history.  (In my opinion.)  Secondly, BattleTech, in it's own right, doesn't emulate armored combat from the 20th and 21st century very well, either.  (But, that's another topic altogether. - Coming Soon!)

Standard BattleTech Armor is by no means a good representation of Deflective armors, but nor do I consider it purely ablative, either.  It's a two-part laminate that has the means to keep impacts from penetrating and disperse high thermal changes.  In a lot of ways, bullet-proof windshield glass is a good proxy for visualization.  Two panes of a solid substance that ablates with solid enough impacts, sandwiching a flexible plastic layer and glued to it so that when it does try to break, you get a webbing effect, instead of spalling.  Granted, those aren't the materials that BT armor uses, but the idea is about the same, but it's magnitudes stronger.  As the armor takes hard enough impacts, it loses cohesion.  As long as there's still a solid portion left of the section, defensive motion algorithms can put that plate in place of any incoming attack. 

And, Windshield glass can be deflective!  How often is it spattered with sand, gravel, bugs, and other minor detritus at high speeds, but doesn't begin to chip?  Plenty.  Most cars have theirs at a deflective angle, too.  It's more than for just wind resistance and performance.  If glass can handle it, then the magnitudes stronger BT armor should be able to, as well.

BT armor is described as a two-layer laminate.  The outer layer is the thermal protection against lasers and other energy weapons. The inner layer is the impact stopping layer that prevents penetration into the interior mechanisms.  (aside: This actually makes sense if you imagine the thermal layer melts and then rapidly cools back down.  It can take penetrating shots that open holes, and then when hit be thermal energy, the layer melts back into cohesion, if not as strong as it once was.  The impact protection layer can't do that.)

Historically, we do have deflective laminate armors, especially in the decades just before the turn of 3rd millenium and after. (That's right, there isn't a 0th Millenium.  The first was the aughts BC.  ^-^ )  But, they're still deflective.


Other Options
There are other ways to emulate deflection. 

Most I've seen use an 'absorption' value. (Kind of like in Car Wars, though that's not the only game. That's what I thought BAR was gonna be.  Imagine my dismay at the reality.)
That idea is generally intuitive when it comes to an Armor Points system similar to standard BattleTech.  However, with SRMs supposed to be good 'anti-armor' weapons during its inception early before the BattleMech, I think it'd require a different scale of damage to have any meaning.  Besides, I think it was Cannonshop that pointed out BattleTech Damage Points don't necessarily equate to penetration strength.

I've seen item mapping.  Each item, including the armor, gets its own health track or is placed on a grid. (Renegade Tech, anyone?) I had looked at doing the same for BT crit items on a table.  This would require vehicles get similar crit tables like a BattleMech if I were to do it.  Basically, I was looking at assigning the armor in a location to the crit slots an item takes.  Once armor was gone on a crit result, the item would take damage.  While this is an entertaining idea, it takes way too much playing around with record sheets to be worthwhile, especially if you're playing with custom units.  And, as I said, I'd have to map out vehicles with crit tables.  Finally, if there aren't any internals to track, item placement would be very important, especially on the limbs.

(Aside: When trying to do this for the Zentradi Battle Pod, I quickly discovered that the Pod should be laid out more like a vehicle, since the cockpit is so spacious, occupied by a human giant, which led to needing a new hit location table.)

So, that kept me looking for something that I could use that wouldn't take too much modification.  Modifying critical hit results was the best thing I could come up with.  It best fits the idea of armor thickness having an effect.  When it comes to combat vehicles, I'm going to have to expand the turret's armor locations, because a lot of 21st century tanks have uneven thicknesses on their turret, with emphasis going towards the front, where the gun's facing.  But, that doesn't require anything change about the hit-location table of the tank.  Only a special rule that the turret's armor is based on the turret facing when it gets hit.

Thoughts?
While I work on my samples, which may take a few days, stew on this and let me know what you think.


« Last Edit: 08 September 2021, 16:02:20 by Daemion »
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Daemion

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Re: Emulating Deflective Armors Without BAR - Crit Chance version
« Reply #1 on: 23 October 2021, 00:04:19 »
While I haven't quite gotten around to the Mega-Force vehicles yet, I already have some sample units in what I will be calling the RoBattleTech Destroid Thread.  I say that because they will be using my upcoming RoBattleTech Rules annex for crit items, ordinance and other stuff.  Do not confuse these with the PalladiumTech versions, which will have their own PalladiumTech Rules Annex, as that's just putting the Pallidium stats, modified for BT scale damage, onto a crit table.

If you look at any of these RoBattleTech Destroid Sheets, you'll see that each item has a number in front of it.  That is the Deflective armor value for that item, derived from Palladium Stats.

If you were to strike a Destroid, you would then go to location rolled, then roll on the location's crit table, then, you would roll a crit chance on that item.  The value in front of the item in parenthesis is your target value.  You need to exceed it to score a crit on that item. 

The level of crit damage can be important.  To find that level, divide your margin of success in half, then round any fractions up to the nearest whole number. 

If the item is on a limb, like an arm or leg, then the arm at that crit slot and below is blown off.  Those crit items are lost to the Mech and are treated as rerolls.  In the case of a Destroid head, only certain items will blow off, and that will be that crit and anything above it.  The items in question will specify in their rules.  Otherwise, the destroyed item remains.

In the case of ordinance lists, the number of crits scored is the number of missiles lost. 

The strength of a crit in the crew compartment on the head that doesn't hit the pilot will damage the pilot beyond whatever it took to crit the item, like sensors or life support.

These will be covered again in the Rules Annex.  I just wanted to showcase how this deflective armor system worked on something resembling a Mech.
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Daemion

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Re: Emulating Deflective Armors - Crit Chance Target Version
« Reply #2 on: 23 October 2021, 00:26:01 »
Assigning Deflective Armor to Locations
Deflective Armor is going to usually assigned by points.

So far, I don't have a hard limit on the point-per-ton range.  However, Primitive armor only grants (I believe) 8 points per ton, and that's still semi-ablative, if I'm right.

Deflective Armor can be looked at as more Archaic than Primitive.

So, capping Deflective to 7 points per ton makes sense, but that's not a hard rule.  I'm actually inclined to cap it at 10, actually.  But, that would be advanced armor for advanced cultures outside of the Inner Sphere. 

For minor variations in between whole numbers, you don't have to limit yourself to half-ton lots.  However, I do recommend you keep it to one decimal place.  (In otherwords, you could have an armor that assigns 1.6 points per ton, or 9.9, or 0.5.)

(Aside: I know that I like something closer to 2 points per ton for near 20th and 21st century metals and laminates, and that is where the Mega Force vehicles will land.)

The notion is that the lighter the armor, the more you can cram inside a vehicle or Mech in the freed-up tonnage.  But, that doesn't mean you can't abuse more advance metals to create something like 'True Armor' out of Battlefield Earth.

Remember that with deflective armors, the point allocation should be uneven, and that locations like turrets and limbs will have to assign values to additonal facings.  Turrets on Vehicles will have to generate values for four sides.  For units with critical item tables, it is best to assign values to each critical slot.  For AeroFighters and DropShips, it would require having the hit location table present on the sheet with the values next to the different critical items.

So, in many cases, you might not get the super hard nut that you were originally thinking.

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Daemion

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Re: Emulating Deflective Armors Without BAR - Crit Chance version
« Reply #3 on: 23 October 2021, 00:39:40 »
Optional Rules
But, these are already optional rules by being in the fan boards.  How can there be options to what is already optional?

Weapon Penetration Values
One of the things I'm not playing around with, yet, but could come into play is a weapon's penetration value.  For this, we can look at the BAR system from the Support Vehicle construction rules.  More specifically, the fact that BattleTech weapons are fully effective against what is BAR 10 armor.  They effectively have a BAP value of 10.  This can be used to handle unnecessarily high crit targets.

For other eras and lesser weapons, you could assign a different BAP to fit.  Suddenly the Tac Ops Rifled Cannons have a different application to the APFSDS standard munitions.  While they may not do appreciable damage against BattleTech's advanced Semi-Ablative armor, they can have a higher chance of scoring a crit with a high effect value against pure Deflective Armor. 

This is an optional rule because it's an added complication, adding in more math.  With that kind of interaction, you might need to balance it against whatever point/tonnage you've decided on. 


Destructive Weaponry
It is safe to say that BattleTech attacks are meant to be highly destructive.  The term anti-material would certainly apply.  Even though Deflective Armor is slow to lose integrity or ablate, it still does.

To reflect this, all standard BattleTech Weapons are considered Destructive.  Anything that is customized for the era or setting you're putting your deflective armor into will have to have such a distinction made when it's assigned. 

Any time deflective armor is hit by destructive weapons, the value for the location or item struck is reduced by one.




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Every thought and device conceived by Satan and man must be explored and found wanting. - Donald Grey Barnhouse on the purpose of history and time.

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Daemion

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Re: Emulating Deflective Armors Without BAR - Crit Chance version
« Reply #4 on: 23 October 2021, 00:41:19 »
That should be it, for now.

Let me know if you have any questions, comments, or criticisms.

I plan on putting this to use this weekend with the RoBattleTech Card-free sheets.

I'll post my thoughts on the system afterward.

It's your world. You can do anything you want in it. - Bob Ross

Every thought and device conceived by Satan and man must be explored and found wanting. - Donald Grey Barnhouse on the purpose of history and time.

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DevianID

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Re: Emulating Deflective Armors Without BAR - Crit Chance version
« Reply #5 on: 24 October 2021, 22:16:46 »
So if you use the existing BAR, but combine it with damage thresholds, it works a lot better.  The BAR2 has a 2% threshold, and BAR9 has a 9% threshold.  Thus to prevent a 5 damage medium laser from penetrating BAR2 armor, you need 201 if rounding up or 250 if not rounding.  BAR9 needs 44 points if rounding up or 56 if rounding down.  This is for aerofighters/dropships, who have a 10% threshold using BAR10 armor normally.

Ground vehicles would need a better threshold than 10% of fighters, so 20% is a workable base.  BAR2 would need 101-125 points to stop a medium lasers, and BAR9 would need 22-28 points, depending on how you choose to round.  (I recommend rounding down as a certain amount of armor is needed to stop even the smallest .50cal--armor doesnt seem to round up IRL)

This threshold system would better model existing penetration values, as 1000mm of RHA BAR3 armor is as good as 600mm of BAR5 chobam using crude equivalencies, so less points of BAR5 are needed to stop any particular attack.
« Last Edit: 24 October 2021, 23:14:19 by DevianID »

DevianID

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Re: Emulating Deflective Armors Without BAR - Crit Chance version
« Reply #6 on: 22 November 2021, 03:11:46 »
Thinking about your idea further Daemion, when we look at the hit chart as a measure of surface area presented (IE a CT is hit more often from the front, thus has more surface area) and take the BTECH armor value as a volume, we can get a crude thickness by dividing by the surface area.  This works out fairly well as the dimensions all cancel out except for 1, thickness.

Thus, from the front and dividing by hit chance by 36, the arms and side torsos have a divisor of 5, the CT has a divisor of 7, and the legs have a divisor of 4.  From the side, the CT has a divisor of 5, which illustrates sloped armor perfectly, while the presenting side has a divisor of 7 now as it is face on.  The base penetration of all weapons is 12+ (TAC roll chance), plus a difference based on the thickness value versus the damage value.

Practical examples: a 25 ton mech with max armor, from the front, has 12 armor in the CT and 8 on the arm.  The front divisor means he has a thickness of 2 in these areas (8/5, rounded up for arm, 12/7 rounded up for CT).  Thus a medium laser, damage 5, would get a +3 bonus to the damage roll, and gets a crit on a 9 (28%) instead of a 12.  So after firing 3.6 medium laser shots, you can expect 1 crit versus this 25 ton mech.  Firing 3.6 medium lasers is 18 damage, so in normal btech terms you would need to hit the CT 3 times (6%) or hit the same arm or leg 2 times (84%) to go critical, meaning the napkin math lines up really well.  A PPC instead of a medium laser, 10 damage versus 2 thickness, gets a +8 to the roll, so on a 4+ (92%) you go critical.  In standard, the PPC goes critical anywhere but the CT/Legs, so 61% of the time, however the second/third shots have a much higher chance, so again the math is pretty close over the average when you factor not tracking damage bubbles.

So you can get deflective armors that match the survivability of standard ablative armors with a quick damage divisor, and you only have to roll to pen instead of tracking damage bubbles.  It would play out like warthunder or world of tanks a bit as the side facing armors are thinner when you flank (and the rear even more so).

Daemion

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Re: Emulating Deflective Armors Without BAR - Crit Chance version
« Reply #7 on: 24 November 2021, 14:39:31 »
So, I'm not exactly following either of your ideas.  I think I get the second, but your first post in this thread doesn't register.

Could you maybe break down each idea, please, so that I can follow?

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DevianID

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Re: Emulating Deflective Armors Without BAR - Crit Chance version
« Reply #8 on: 25 November 2021, 05:38:46 »
No problem, I tend to overwrite my points.

In the first post, I mention how BAR armors can provide a threshold as a % equal to the BAR (standard armor is BAR10, so 10%), and ground vehicles can double the value versus aircraft.  So 50 points of BAR2 would provide a threshold of 1 on an aircraft, and 2 on ground vehicles.  Likewise, a unit with BAR9 would have a threshold of 5 for aircraft, and 9 for ground vehicles, with 50 armor.  This replaces the normal BAR rules, so a huge ground vehicle with 150 points of armor in the front, with bar5 armor would have a threshold of 15 instead of 5 due to how thick the armor is, but a tank with modern BAR 10 armor with 20 points would only have a threshold of 4 (2 for 10% of the armor, doubled for being a ground vehicle).

The second idea is to completely replace the armor bubbles with a damage penetration roll, where we just track critical hit rolls.  In this, your armor is divided by how likely the shot was to hit out of 36.  Since this is all known already, in place where armor bubbles go would be the damage reduction value.
A marauder from the front, with 35 armor on the CT, has a front reduction value of 5 (35 armor, divided by 7 for 7/36 chance to hit) from the side it is 7 (35 divided by 5, because of a 5/36 chance to hit), and from the rear it is 1 (10 rear/7, if rounding down).  The base chance to pen is 12, +weapon damage, -armor deflection value.  A 12 always pens (snake eyes TAC).
So a clan ER medium laser at 7 damage needs a 10 to pen the chunky center torso, but a 12 from the side, and only a 6 to pen the rear.
The point of the second system is to model how damage looks in a system like War Thunder, where armor either stops the round or the round gets through the armor do deal critical damage.

Daemion

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Re: Emulating Deflective Armors Without BAR - Crit Chance version
« Reply #9 on: 17 January 2022, 09:35:00 »
Much clearer.  Both are interesting ideas.

I'm not too keen on salvaging BAR.

However, your second idea is one I find heading in the direction I want to go.  BattleTech is known for having destructive weapons, so I would be interested in some form of decaying value.  If we were to go this route, maybe we could apply Alpha Strike values to how much the armor depletes after each hit.

---

I'm tweaking my current idea presented only lightly.  I really like the notion of a psuedo-RenegadeTech.  So, when it comes to Mech(a), I'll still map out armor by items on anything with a crit table.  I'll try to come up with some sort of points per ton system to mesh with the BT Construction system.  However, I know that a lot of leeway will have to be given since a lot of Mecha hulls and their performance are not limited in that way.

We tried out my initial idea where the armor was only lightly impacted by the damage or type.  My friends found the MoS application to the RoBattleTech Mechs a bit much.  I agree. 

The MoS thing only works best when there are small amounts of things to track.  And, with RoBattleTech, it really is scaling the stats and success ratios to BT levels. (This is important to me, since I'm working on cross-over encounters.  So, when BT defensive countermeasures are in play, that's the level required to hurt regular BT units. I'm trying to showcase equipment of poorer quality under those constraints.)

But, that will be dealt with in that rules annex.

So, this has me wondering how to handle units like the MegaForce conventional vehicles.  Unless I decide to map them with crit tables, which is entirely possible, I'm stuck with the current BT vehicle set-up with only armor locations and Internal Structure or Structural Integrity. 

Your application of a TAC on Nat 12, borrowing from the Aero rules, sounds like a good solution for hard armor with high or impossible deflection values.


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Daemion

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Re: Emulating Deflective Armors Without BAR - Crit Chance version
« Reply #10 on: 11 February 2022, 23:49:51 »
The second idea is to completely replace the armor bubbles with a damage penetration roll, where we just track critical hit rolls.  In this, your armor is divided by how likely the shot was to hit out of 36.  Since this is all known already, in place where armor bubbles go would be the damage reduction value.
A marauder from the front, with 35 armor on the CT, has a front reduction value of 5 (35 armor, divided by 7 for 7/36 chance to hit) from the side it is 7 (35 divided by 5, because of a 5/36 chance to hit), and from the rear it is 1 (10 rear/7, if rounding down).  The base chance to pen is 12, +weapon damage, -armor deflection value.  A 12 always pens (snake eyes TAC).
So a clan ER medium laser at 7 damage needs a 10 to pen the chunky center torso, but a 12 from the side, and only a 6 to pen the rear.
The point of the second system is to model how damage looks in a system like War Thunder, where armor either stops the round or the round gets through the armor do deal critical damage.

Work out some stats for the core 2nd ed Mechs, and I'll see if I can't work up some sheets once you do.  This sounds interesting.

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Daemion

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Re: Emulating Deflective Armors Without BAR - Crit Chance version
« Reply #11 on: 12 February 2022, 00:43:47 »
So, an update:
We tried the RenegadeTech-Simplified version of RoBattleTech, and it worked much better. 

As I had stated initially, instead of applying damage as soon as the location hit is rolled, the critical item hit is rolled next, because it has its own armor value.  After the armor on the item takes damage, roll a crit chance against the remaining armor value as your target. 

The biggest complication I had was figuring out how to apply the missile damage from RoboTech stats to this system.

However, I'm looking at this system, and it feels more like 'true ablative' armor.  Let me explain.

BattleTech armor, as I see it, isn't purely ablative.  Many aspects in the game suggest that it is what I call semi-ablative, a mix of deflective and ablative properties.  This can easily be an effect of two armor layers with different defensive properties.  Suffice it to say, as long as there is at least one point of armor left, a location is protected against breaches barring a die roll.  Once that last armor point is gone, it can be flooded or exposed to vacuum. (v)

But, in spite of that, while internal structure is damaged, the chance of item failure from damage is less than 50%.  This suggests to me that the armor may have holes, but it isn't completely gone.  You don't get auto-crit effects.  You don't get to pick an exposed location and get some sort of to-hit bonus reduction to target it, or anything like that.  And, you can't target specific items in an exposed location, either.  You still have to roll which item takes the hit.  (Game artifact for simplicity?  Sure.  But, it's there.  Let's work with it.  ;)  )

I see both deflective and ablative properties in that.  Especially in a setting that uses speed of light attacks like lasers.

Purely ablative armors would leave the holes exposed and potentially available to exploit.  This is emulated very well in Renegade Legion games with the mapped armor and internals, as well as RenegadeTech.  There is a chance you'll hit that hole again, or another one. 

It does not make me think of deflective armors.  Sure, deflective armors will open up holes, but they're usually going to be small.  And, once a hole is opened up, bad things have happened on the inside. 

I still like the idea of the armor being the base point for determining if a crit is made. 

But, for it to feel deflective, there are two things I'll have to go back to:
1) Armor by location - or hull sections -  Instead of mapping out the armor applied to each crit item by slot, it's done by hull sections.  Maybe not even that, but full location.
2) Damage has little to no effect to the overall armor value, with some exceptions.


I can do this easily for tanks, but something like a BattleMech will be a little more difficult.  For example, the Palladium Tech sheets in the custom Mech Designs sub-section would be ideal.

I'll need some time to mull over this, and once I have something satisfactory, I'll get back with the results.


 
It's your world. You can do anything you want in it. - Bob Ross

Every thought and device conceived by Satan and man must be explored and found wanting. - Donald Grey Barnhouse on the purpose of history and time.

I helped make a game! ^_^  - Forge Of War: Tactics