Advanced Rules: Realistic Mech Movement (optional house rules)

[Daryk]

Realism is the strongest possible argument against LAMs.

And, since this is a thread about ground movement rules, let´s maybe stop bringing non-ground movement into this over and over and over again.

The harder you make a thing, the more people will look for alternatives to that thing.

[Sir Chaos]

The harder you make a thing, the more people will look for alternatives to that thing.

Then do so elsewhere, not in a thread that is exclusively about the thing.

[Daryk]

Roger, out.

[EDG]

Then do so elsewhere, not in a thread that is exclusively about the thing.

Thank you. It's hard enough to get focussed discussion on a subject that requires some thought, it's even harder when people insist on trying to derail it. (though I guess it's too late now...)

[Sir Chaos]

There may be arguments for allowing them to go faster. I don't know what the theoretical maximum possible speed that a biped could run is (it could possibly be calculated given how fast the legs could swing given their mass and momentum etc) - some have claimed that humans can potentially reach speeds up to 65 kph (Fr~37) but that's a theoretical limit that we're probably going to get nowhere near in reality. 4-5 steps per second seems to be the practical limit now. I used an Fr of 12.345 as the "top speed" because that's the equivalent of Bolt's record-breaking 100m sprint. He did go faster for a 20m subdivision of that (up to Fr~17) and maybe it's possible to go even faster. But the idea is that a mech going at that speed is going all out - OK, so they don't have lungs and fatigue toxins and lipids to worry about but their stride is still going to be about as long as it can be, they're doing about 4 steps per second, the arms probably have to be swinging to some extent, etc. In a way I allow for faster speeds with MASC and the other boosters though - hey, maybe they can all have that installed in the extra space that their smaller engines free up! Could even explain it by them losing the tech in the succession wars so the light mechs weren't so fast and useful anymore, but then they regain it later on to reach their full potential again.

I was thinking about that but figured that Weak Legs was there and I could just make that more extreme. I didn't want to have them be crippled and super vulnerable by having Long Legs.

I think you may be leaning a bit too much into the comparison with humans. A mech´s myomer "muscles" might be considerably more capable than anything biological, for example.

The bit about the swinging arms suggests another rule - mechs that are Sprinting cannot use arm-mounted weapons because the arms need to be able to swing to keep up the speed.

The thing about Weak Legs is that it only affects melee attacks, which should be a fairly small part of combat, and an even smaller part of the life of a fast scout or skirmisher - and the part about DFA attacks does not apply to mechs without jump jets at all. With the added drawback of being more vulnerable to being knocked over by taking damage, using Long Legs would create a clearer difference between designs meant to scout and designs meant to fight - a capable commander would be even less tempted to use a mech designed for one role in the other than they already are under the official rules.

[EDG]

I think you may be leaning a bit too much into the comparison with humans. A mech´s myomer "muscles" might be considerably more capable than anything biological, for example.

I hesitate to ascribe any magical properties to myomer considering we know nothing about its capabilities.
The limit isn't really the myomer, I'm talking about physically being able to get the legs to move fast enough. The step size is getting bigger when sprinting, so it takes longer for the legs to swing back and forth - so I think there must be a limit to how rapidly the legs can complete the stride cycle.

The bit about the swinging arms suggests another rule - mechs that are Sprinting cannot use arm-mounted weapons because the arms need to be able to swing to keep up the speed.

technically mechs shouldn't be able to fire anything when Sprinting (by the definition here) or in Overdrive, but I figured that there'd be lots of howling if I said that mechs couldn't fire when sprinting.

The thing about Weak Legs is that it only affects melee attacks, which should be a fairly small part of combat, and an even smaller part of the life of a fast scout or skirmisher - and the part about DFA attacks does not apply to mechs without jump jets at all. With the added drawback of being more vulnerable to being knocked over by taking damage, using Long Legs would create a clearer difference between designs meant to scout and designs meant to fight - a capable commander would be even less tempted to use a mech designed for one role in the other than they already are under the official rules.

Again, I made that decision because I didn't want people to start complaining about how much more vulnerable the legs (and/or mech) would become.

[Lycanphoenix]

Hmm... I don't suppose you could build a bicycle for a mech?

[EDG]

Hmm... I don't suppose you could build a bicycle for a mech?

Or say, ditch those pesky legs completely and just use wheels or tracks or hover propulsion ;)

[Charistoph]

It would make QuadVees more justified, if anything...

Still, I'm not on board with this.  For example, an elephant isn't going to be moving as fast as a rhino, which has much shorter legs, much less an ostrich or a cheetah, despite having the longest legs of any land animal.  The construction of their legs and the way their muscles are built, to say nothing about the overall mass of the animal, are what counter this capacity.

And as others have mentioned, it is a game.  The changes do not provide sufficient justification on a gameplay perspective to even consider going through with this.  Relying on Quirks to provide justification for differences is a significant problem when they should be tied to construction factors.  If Walking was limited to 90m for ANY 'Mech, with Running going up to what is currently available for the unit, that might be a direction to go with.  However, Locusts being slower than an Atlas is just game-breaking.

[EDG]

Still, I'm not on board with this.  For example, an elephant isn't going to be moving as fast as a rhino, which has much shorter legs, much less an ostrich or a cheetah, despite having the longest legs of any land animal.  The construction of their legs and the way their muscles are built, to say nothing about the overall mass of the animal, are what counter this capacity.

Having longer legs doesn't mean you're automatically faster - it just means you can be *potentially* faster.

If Walking was limited to 90m for ANY 'Mech

It is, here. All mechs walk either 2 or 3 MP. And most of the heavier mechs at least can run (or sprint) as fast as they can in the current rules.

However, Locusts being slower than an Atlas is just game-breaking.

Uh, they're not? Locusts move 3/5/7/10 here. At Atlas moves 3/5/-/-. The Locust can Sprint up to 7 and Overdrive up to 10, the Atlas can't move (Run) faster that 5 (I mean can you honestly imagine an Atlas sprinting normally? Though with MASC it actually could - and that would be pretty terrifying since it could then go up to a maximum of 13 - but I can't do that normally :) )

[Charistoph]

Having longer legs doesn't mean you're automatically faster - it just means you can be *potentially* faster.

That actually is the premise behind these changes.

It is, here. All mechs walk either 2 or 3 MP.

But not all are going 3, in fact, only half are.

Uh, they're not? Locusts move 3/5/7/10 here. At Atlas moves 3/5/-/-. The Locust can Sprint up to 7 and Overdrive up to 10, the Atlas can't move (Run) faster that 5 (I mean can you honestly imagine an Atlas sprinting normally? Though with MASC it actually could - and that would be pretty terrifying since it could then go up to a maximum of 13 - but I can't do that normally :) )

Only with a Quirk, and not any construction mechanics.  Even then, an Atlas is outrunning almost every other Light.

And yes, I can imagine an Atlas sprinting normally because of American football, and it currently can in the rules if anyone can Sprint.

[EDG]

That actually is the premise behind these changes.

...yes? What's your point?

But not all are going 3, in fact, only half are.

Yes, because smaller mechs generally have shorter legs. Do you actually understand that the point of this is to have mechs that moved the way I described in my previous "How fast can a Battlemech walk?" article?

Only with a Quirk, and not any construction mechanics.  Even then, an Atlas is outrunning almost every other Light.

Which part of "The fastest an Atlas moves is 5, the fastest Locusts move is 10" are you not understanding? Atlases do not outrun lights.
And as far as I'm concerned, Quirks are there to allow mechs to do things differently when they're designed. Long Legs seemed a logical way to allow mechs to move faster than they normally could. How else would you do it?

And yes, I can imagine an Atlas sprinting normally because of American football, and it currently can in the rules if anyone can Sprint.

The bigger American footballers do not usually sprint. The idea of a Goliath doing a full gallop is kinda silly to me too.

[Lycanphoenix]

I think the issue with the Long Legs quirk is that design quirks are supposed to be an optional rule, but when a quirk becomes central to a mech's design, it stops being optional.

[EDG]

I think the issue with the Long Legs quirk is that design quirks are supposed to be an optional rule, but when a quirk becomes central to a mech's design, it stops being optional.

Then there'd be no way to give some mechs an ability that others don't (Long Legs, in this case). And since it suggests that negative quirks be used to balance out the positive ones I added the Weak Legs condition too. There's just no way to do this without quirks (otherwise there's no limit to what mechs can have Long Legs).

Though I have to laugh that people are getting upset about me using quirks when I'm redoing the whole movement system here - it's pretty much the least "offensive" thing I'm proposing here.

[Lycanphoenix]

I am also a big fan of quirks. And personally, I don't mind this realistic movement thing.

[Sir Chaos]

My problem isn´t with the fact that quirks are used, it´s that the benefits of Long Legs appear to outweigh the drawbacks.

[EDG]

My problem isn´t with the fact that quirks are used, it´s that the benefits of Long Legs appear to outweigh the drawbacks.

The benefit is just that the mech can possibly run faster. I didn't want Long Legs to be a huge liability - I think making them more vulnerable to weapon damage or having to make a piloting roll every time they took damage would have gone too far.

[Charistoph]

...yes? What's your point?

Your premise is that longer legs equal faster speed, but that doesn't necessarily translate out in reality, which you then denied.

Yes, because smaller mechs generally have shorter legs. Do you actually understand that the point of this is to have mechs that moved the way I described in my previous "How fast can a Battlemech walk?" article?

Because they aren't ALL Walking 3.

Which part of "The fastest an Atlas moves is 5, the fastest Locusts move is 10" are you not understanding? Atlases do not outrun lights.
And as far as I'm concerned, Quirks are there to allow mechs to do things differently when they're designed. Long Legs seemed a logical way to allow mechs to move faster than they normally could. How else would you do it?

Because it doesn't match the charts.  The fastest an Atlas moves is much faster than 5.

Quirks are there to do things construction rules do not or cannot normally address, but are represented in the story of the 'Mech's designed.

What should be done is alter construction so the length of the legs is determined as part of the Structure.  Something like reducing the amount of Internal Structure the Leg has to provide a less dense leg structure, but increases its overall movement, such as the ostrich legs of the Locust.  Meanwhile, a stubbier leg structure would do the opposite, providing more Internal Structure, allowing for more Armor, but reducing its pace, such as the elephant legs of the Urbanmech.

The bigger American footballers do not usually sprint. The idea of a Goliath doing a full gallop is kinda silly to me too.

You've never been to an American football practice, have you?  Sprinting is part of physical development.  The linemen may not do much of it in a game (usually for defensive linemen that break through for a sack), but I assure you they still do it between games.  Then there are the fullbacks which usually sprint INTO the line for the momentum to burst through.

[EDG]

Your premise is that longer legs equal faster speed, but that doesn't necessarily translate out in reality, which you then denied.

That isn't my premise at all. A biped can potentially move faster with longer legs. It doesn't mean they're automatically faster.

Because it doesn't match the charts.  The fastest an Atlas moves is much faster than 5.

what charts? An Atlas in the RAW can potentially sprint in the official rules and move faster than 5, sure. It can't here (without MASC), so what's your point? My rules are different from the official rules.

What should be done is alter construction so the length of the legs is determined as part of the Structure.  Something like reducing the amount of Internal Structure the Leg has to provide a less dense leg structure, but increases its overall movement, such as the ostrich legs of the Locust.  Meanwhile, a stubbier leg structure would do the opposite, providing more Internal Structure, allowing for more Armor, but reducing its pace, such as the elephant legs of the Urbanmech.

Yeah well I'm not going to revamp the entire design system, sorry. If I'm using quirks in a different way to how they're intended then mea culpa, but I think what I did works well enough for this purpose.

[Lycanphoenix]

This is starting to get a little bit heated. Maybe we should calm down a bit?

[EDG]

This is starting to get a little bit heated. Maybe we should calm down a bit?

Sure, if people could read the articles and understand them first.
A lot of pushback I get from this whole thing is from people just not understanding that scaling bipeds up doesn't actually work the way they think it should. They rattle off some back of the envelope "proof" by multiplying everything linearly ("a Mech is 4-5 times taller than a human so should be 4-5 times faster too") and declare I must be wrong based on that when I know I'm not (and have the science to prove it, and explained it all in the articles anyway).

If something isn't clear or doesn't make sense to you then by all means ask me to explain further, but please don't tell me I'm wrong just because what I'm saying doesn't agree with your assumptions, and please don't tell me I'm saying something that I'm not. It gets pretty tiresome to have to keep repeating the same things over and over.

[VanVelding]

These are cool, optional rules clearly rooted in reality.

Do you want to use it but not use quirks? Kick around some solutions. This isn't the first optional rule system that requires other optional rules.

Does it upset game balance? A bit, yeah. If you want to use it, that's also your row to hoe. Y'know, be part of the solution.

If you don't want to use it...don't?

[Sir Chaos]

Another thing to consider is: How do quad mechs differ from bipedal mechs in terms of movement? Animals like the antelope or cheetah, though of broadly similar size to humans, can run a lot faster than humans.

Could faster ground movement, compared to bipedal mechs, be the niche of quads under more realistic rules? And could they (since apparently a horse at full gallop is actually a pretty stable platform for mounted archery) also generate smaller attacker movement modifiers, and/or face fewer restrictions for firing while sprinting oder using overdrive?

I´ve always rather liked quads as a concept, and thought it´s a shame the current rules don´t give them more of an advantage to offset their drawbacks.

[EDG]

Another thing to consider is: How do quad mechs differ from bipedal mechs in terms of movement? Animals like the antelope or cheetah, though of broadly similar size to humans, can run a lot faster than humans.

I'm not sure if quadrupeds are faster simply because they have four legs. And they don't use a different formula to calculate their Froude number either. They certainly have a few more gaits - trot, canter, gallop etc but they're broadly variations of "Walk", "Run" and "Sprint".

Could faster ground movement, compared to bipedal mechs, be the niche of quads under more realistic rules? And could they (since apparently a horse at full gallop is actually a pretty stable platform for mounted archery) also generate smaller attacker movement modifiers, and/or face fewer restrictions for firing while sprinting oder using overdrive?

This is a horse galloping in slow motion:
https://www.youtube.com/watch?v=86Zu8mqd8LM

Can you imagine a Goliath galloping like that? I have them capped out at Run 5 which is fine, but a full sprinting gallop? I dunno...
A Scorpion definitely wouldn't, its legs are splayed out sideways from its body, more like a lizard's (and are really long too)

I´ve always rather liked quads as a concept, and thought it´s a shame the current rules don´t give them more of an advantage to offset their drawbacks.

It would be nice if they had some more unique movement abilities, but I never understood why only quads can do the "lateral movement" thing - their legs really aren't designed for that sort of sidestepping.

[Sir Chaos]

I'm not sure if quadrupeds are faster simply because they have four legs. And they don't use a different formula to calculate their Froude number either. They certainly have a few more gaits - trot, canter, gallop etc but they're broadly variations of "Walk", "Run" and "Sprint".

Which kind of begs the question... why are they so fast (the ones that are fast, anyway)? Unfortunately, I doubt either you or I are biologist enough to answer the question.

This is a horse galloping in slow motion:
https://www.youtube.com/watch?v=86Zu8mqd8LM

Can you imagine a Goliath galloping like that? I have them capped out at Run 5 which is fine, but a full sprinting gallop? I dunno...

A Goliath is more like an elephant than like a horse. Fun fact: Elephants can´t run, either.

Now, a Snow Fox on the other hand...

A Scorpion definitely wouldn't, its legs are splayed out sideways from its body, more like a lizard's (and are really long too)

I could see scorpion-legged quads having the ability to move with their torso between their legs, keeping a low profile and making them only one level tall, like a vehicle.

It would be nice if they had some more unique movement abilities, but I never understood why only quads can do the "lateral movement" thing - their legs really aren't designed for that sort of sidestepping.

Elephant-legged quads, yeah, they aren´t built for that. But scorpion-legged ones might pull it off. IIRC crabs, with a leg plan kinda similar to scorpions, can move sideways relatively easily.

[EDG]

Which kind of begs the question... why are they so fast (the ones that are fast, anyway)? Unfortunately, I doubt either you or I are biologist enough to answer the question.

It's probably down to a lot of things - their mass, relative leg length, muscle distribution, etc.

A Goliath is more like an elephant than like a horse. Fun fact: Elephants can´t run, either.

Interesting article about that: https://www.sciencedaily.com/releases/2003/04/030404071405.htm

They can *kinda* run. In fact it could offer a way out for battlemechs to walk faster, if they actually move the same way as elephants (assuming that mechanism would work with bipedal walkers).

I could see scorpion-legged quads having the ability to move with their torso between their legs, keeping a low profile and making them only one level tall, like a vehicle.

Elephant-legged quads, yeah, they aren´t built for that. But scorpion-legged ones might pull it off. IIRC crabs, with a leg plan kinda similar to scorpions, can move sideways relatively easily.

Yes, but crabs and scorpions have more legs too. The Scorpion or Tarantula mechs might be able to move like that given their splayed out leg plan though. I'm not sure if having different types of quad mech is going to overcomplicate things though...

[Sir Chaos]

Yes, but crabs and scorpions have more legs too. The Scorpion or Tarantula mechs might be able to move like that given their splayed out leg plan though. I'm not sure if having different types of quad mech is going to overcomplicate things though...

I would handle that one via quirks, much like VTOL rotor arrangement.

Elephant-legged quads get a free level of Long Legs without drawbacks, and can go to Long Legs 4 (with 1 level of the drawback per level beyond the first).

Scorpion-legged quads could get the ability to side-step, the way all quads previously could. Or as an alternative, they could get the ability to run, sprint and overdrive backward in addition to forward, since their legs are built so differently from bipeds or elephant-legged quads.