this post was submitted on 09 Sep 2023
404 points (97.4% liked)

NonCredibleDefense

3493 readers
5 users here now

Rules:

  1. Posts must abide by lemmy.world terms and conditions
  2. No spam or soliciting for money.
  3. No racism or other bigotry allowed.
  4. Obviously nothing illegal.

If you see these please report them.

Related communities:

founded 1 year ago
MODERATORS
 
top 50 comments
sorted by: hot top controversial new old
[–] [email protected] 87 points 1 year ago (2 children)

First, you tell us walking is better for the environment and then you tell us that it won't be possible because some stupid numbers law thing? What do you expect us to walk on? Our own fucking meaty feet?! They go all ouchie after a time!

[–] [email protected] 22 points 1 year ago (2 children)
[–] [email protected] 19 points 1 year ago

Men only want one thing and it's fucking disgusting

[–] [email protected] 13 points 1 year ago (7 children)

But they don't have an AC/20!

[–] [email protected] 7 points 1 year ago (1 children)

You clearly need to increase your tonnage capacity.

[–] [email protected] 6 points 1 year ago

And ditch the LRM? No way! Without them, I'd need to walk even more!

load more comments (6 replies)
[–] [email protected] 18 points 1 year ago

Our own fucking meaty feet?! They go all ouchie after a time!

[–] [email protected] 71 points 1 year ago (6 children)

Even ignoring the square-cube law, it's just a really bad design. If you look at modern main battle tanks, they have been getting lower profile. This is for the simple fact that not being a massive target sticking up from the terrain is a really useful feature. Even then, they often use terrain to try and lower their visible profile further. Add to that all the complexity of making legs and arms work, and it's begging for a stealthier vehicle to drop the mech with a 105mm penetrator to the knee.

[–] [email protected] 38 points 1 year ago* (last edited 1 year ago)

Patlabor addresses this somewhat. Bipedal mech started as a way to rapidly rebuild Tokyo after a massive earthquake. They became so ubiquitous, that regular people had access to them so between drunk/disgruntled construction workers and some bank robberies, Tokyo police had to add two divisions of "Patrol Labors" to deal with it. They're costly and annoying to everyone. The mech carriers are two lanes wide and no body likes giving them the right of way in traffic. After that, the companies making them diversified into military and meches have a limited roll depending on the terrain. Mostly swampy jungles with bad line of sights, so the legs are useful and the high profile a none issue. High end military models are very quiet compared to civilian models.

[–] [email protected] 35 points 1 year ago (1 children)

Ah but the bipedal mech suits could crawl along to floor, given a really low profile. Tank can't do that. Checkmate.

/s

[–] [email protected] 8 points 1 year ago (1 children)

I want to see a Raven crawling on the floor with a low profile.

A Dire Wolf would be quite something too.

load more comments (1 replies)
[–] [email protected] 27 points 1 year ago

I think you are ignoring the very important fact that Gundams are dope.

[–] [email protected] 14 points 1 year ago

In game they introduced regular human sized battlesuits ("elementals"), they gimp mechs pretty much as bad as you're saying.

[–] [email protected] 9 points 1 year ago

Let alone drones. If you don't install OP point defence on every mech, they will all be brought down by drones targetting the legs.

[–] [email protected] 7 points 1 year ago

A taller mech has better reach. It helps when fighting with fists and swords. Checkmate!

[–] [email protected] 69 points 1 year ago* (last edited 1 year ago) (2 children)

If square-cube law then how T-Rex? Checkmate engineers.

[–] [email protected] 34 points 1 year ago (1 children)

What T-Rex? Square cube law dealt with them years ago!

[–] [email protected] 23 points 1 year ago* (last edited 1 year ago)

"Square cube law cast Meteor! It was super effective!"

[–] [email protected] 5 points 1 year ago (1 children)

Fuckers had no arms! Who wants to do leg day every fucking day?!

load more comments (1 replies)
[–] [email protected] 35 points 1 year ago (7 children)

Note: like most memes I post, this is not mine. Specifically, I am not an engineering student; I passed high school math with a 59.5%.

[–] [email protected] 12 points 1 year ago* (last edited 1 year ago) (5 children)

In the same spirit: I laughed at this and upvoted it, but I don't know what the square cube law is or what it has to do with mechs. I don't really understand the joke and I'm honestly a fraud for upvoting it and engaging with it, at all.

[–] [email protected] 29 points 1 year ago (2 children)

The square-cube law is the rule saying that if you increase something's size, its volume will also increase proportionally.

Ie: if you have a 1x1x1 cube it's volume is 1, but if you have a 2x2x2 cube it's volume is 8.

With mech design, making a huge bipedal robot means putting a massive amount of weight on relatively weak joints at the legs.

[–] [email protected] 6 points 1 year ago (1 children)

Thanks, I don't think I like the square-cube law. Just make the joints stronger. It'll be fine!

[–] [email protected] 15 points 1 year ago* (last edited 1 year ago)

The square-cube law is also why we don't have giant spiders, so it's not all bad.

(a cow sized spider would have legs as thick as matchsticks, and as intuition would suggest, collapse hilariously on itself.)

[–] [email protected] 9 points 1 year ago* (last edited 1 year ago) (1 children)

Think about any part of your body... say your arm. Now imagine scaling it up to double the size.

Your muscles are now double the length but also have to move a doubled distance. That changes nothing.

That same muscle (it's roughly a tube) has doubled it's diameter, so it 2² = 4 times as strong because it's cross-section is a circle and the surface of a circle is (d/2)² * pi.

But your whole arm has doubled it's size in all 3 directions. So it's volume/mass is now 2³= 8 times as high.

So in short: double your size and you are 2² = 4 times as strong, but you also have to move 2³ = 8 times the mass. That's the square/cube thing that makes just scaling up impossible.

PS: Yes, if you ever wondered how you were so incredible good at climbing things when you were a child... small children are much stronger than you compared to their own body weight.

[–] [email protected] 5 points 1 year ago

Ohhhhhhh! Thanks, this helped with the "why."

[–] [email protected] 5 points 1 year ago

In addition to what others here have said, it is also the cause of scaling fall damage.

An ant falles down a mine shaft and doesn't even notice.

A mouse bounces and runs off.

A person breaks.

A horse splashes.

Surface area decreases max fall speed. Mass increases max speed. Mass times speed indicated how much force something feels at the end of the fall. The issue is, surface area scales as a square, Mass as a cube, and thus the bigger something has the less drag it has and the more energy it absorbs as it lands, getting hit coming and going.

[–] [email protected] 4 points 1 year ago

Fake it 'til you make it!

The square-cube law is about how increasing the size of an object increases its volume much more rapidly. So if you make an ant, say, twice as large, it ends up 4 times as heavy (don't take these numbers as anything but an example, I'm pretty sure there's formulae and shit). For that reason, massive vehicles, like mechs, are impractical - something twice as large as a tank is gonna end up much more than twice-as-heavy.

load more comments (1 replies)
[–] [email protected] 4 points 1 year ago (1 children)

Thank you for the transparency

[–] [email protected] 9 points 1 year ago

I would hate to be convicted of meme fraud!

load more comments (5 replies)
[–] [email protected] 21 points 1 year ago

My headcanon is that mechs require a few things to be a viable weapons platform:

  1. Orbital bombardment is not a viable tactic
  2. FTL travel is cheap and easy for non-living matter
  3. FTL travel is expensive and/or prohibitively dangerous for living tissue
  4. Artificial intelligence / fly by wire is not viable

If 1 isn't true, then toss rocks at them from space and pick up the pieces later.

If 2 isn't true, then it would be easier to train local forces and use commando teams

If 3 isn't true, then it would be cheaper, easier, and more effective to deploy rapid response forces of mixed armored infantry.

If 4 isn't true, then send your swarms of autonomous weapons platforms to kill anything that moves.

I'm sure there's a few other reasons why Urbanmechs would make more sense than the larger platforms, but at some point you just gotta enjoy the mecha

[–] [email protected] 18 points 1 year ago* (last edited 1 year ago) (2 children)

Actually, did the surface area math for a Timberwolf/Madcat mech years and years ago and they were (unexpectedly) fine.

They had something like 25% more surface area per foot than a challenger 2 does with both treads.

The bigger issues are that chicken walker legs don't work to support 60 some odd tons of weight, and that the 10-15m height is a little bIt too noticeable

[–] [email protected] 16 points 1 year ago* (last edited 1 year ago) (3 children)

I don't even care about the legs or the structure, I care about the ground.

Walkers would obliterate pavement and sink so deep into the mud.

The walkers would need hilarious duck feets

[–] [email protected] 16 points 1 year ago

I'm all in on clown shoe mechs

[–] [email protected] 5 points 1 year ago
load more comments (1 replies)
load more comments (1 replies)
[–] [email protected] 17 points 1 year ago (2 children)

Why bipedal when it can have a support tail like a Kangaroo?

load more comments (2 replies)
[–] [email protected] 15 points 1 year ago

Build an ostrich. Problem solved.

DM me for the rates on my consulting fees.

[–] [email protected] 15 points 1 year ago (1 children)

Until we figure out a super strong super light material you can build them out of: All we really need to do is come up with a name for it!

May I suggest: Badassanium?

[–] [email protected] 6 points 1 year ago (2 children)

Carbon fiber! 10 times stronger than steel yet light as a feather!

...

Good luck mass producing that in the correct form though. Carbon fibers, while pretty much our currently best material is so far unusable besides on microscopic application.

[–] [email protected] 5 points 1 year ago (1 children)

We did find out this summer that carbon fiber is horrendous at pressure loads. Might not be the best material for a mech.

[–] [email protected] 4 points 1 year ago

Awesome! We always learn more!

load more comments (1 replies)
[–] [email protected] 12 points 1 year ago* (last edited 1 year ago) (4 children)

I say this too, not as an engineer, but when reading the self important downers in battle forums saying a giant chicken wouldn't beat a lion only because of this stupid law, instead of just entertaining the idea

[–] [email protected] 7 points 1 year ago

They're also completely wrong. You can go see Lucy in Chicago and see with your own eyes the skeleton of the giant chicken that would take out a lion in one bite.

[–] [email protected] 7 points 1 year ago

My hen and I were having a bit of a staredown one afternoon and she instantly and with no warning snapped her head to the side and chomped a bee out of the air, swallowed it, and was immediately back to staring me down.

load more comments (2 replies)
[–] [email protected] 7 points 1 year ago

A world without the possibility of Metal Gear isn't a world worth living in.

[–] [email protected] 6 points 1 year ago (2 children)

a space elevator for ~~nukes~~ payloads will probably come before mechs and that makes me sad

load more comments (2 replies)
load more comments
view more: next ›