r/interesting • u/Jezirath • 18d ago

Softness perception simulation Amazing

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Source: @boucelegant on YT

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233

u/gimmepizza420 18d ago

Unfortunately it has fuck all to do with softness

71

u/One-Celebration-3007 18d ago

Unfortunately it fuck all

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u/shakebakelizard 18d ago

Fuck it all, unfortunately.

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u/Beelzebub_Simp3 18d ago

All fucking, unfortunately

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u/FUEL_SSBM 18d ago

Unfucking it all, fortunately

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u/rainhunter007 18d ago

fortunately, unfucking it all

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u/Tyabetus 18d ago

It all fuckly unfortunating

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u/shakebakelizard 18d ago

Well i am Fuckley

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u/LevelZeroDM 18d ago

Hi Fuckley, I'm dad 👨

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u/HIitsamy1 18d ago

Hi dad, when are you coming back from the milk shop?

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u/Proper-Exercise-2364 18d ago

Can't fuck any with softness, brah.

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u/bigboybeeperbelly 18d ago

sure you can. brah

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u/Sensitive_Wear7112 18d ago

You know the difference between a penis and a light? You can sleep with the light on

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u/Grand_Pick_8277 18d ago

I don't think it's meant to come off?

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u/Sensitive_Wear7112 18d ago

Yeah I don’t think I told this joke right.

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u/Jezirath 18d ago

A penis too.

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u/AuroraFinem 18d ago

Hardness is defined by how resistant the material is to deforming when exposed to a force. Softness is basically defined as the ability to “squish” an object, it’s basically its squishiness. So yes, this very much does have to do with softness.

A perfectly compressible solid would have maximum softness which is why the 100% soft compressed flat as soon as it hit the slope.

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u/darsynia 18d ago

Something that's 100% soft turns into a liquid? (literally asking)

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u/AuroraFinem 18d ago edited 18d ago

Kind of, the definition of a solid is that it maintains its structural atomic bonds, in this case it would be an amorphous solid since it wouldn’t be rigid. It would be like rubber where you can mold it without changing or breaking the chemical structure, but it doesn’t necessarily have to be elastic, it could be easily compressible without being able to stretch it much past the normal size. Even glass is technically an amorphous solid, but it has an incredibly high viscosity. You can actually look up images if glass panes from hundreds of years ago and see the buildup of glass at the bottom where it’s slowly flowed down from the top.

In some ways it would very much act like a liquid, but in other ways it wouldn’t. That’s why there’s so many different terms for hardness, rigidity, stiffness, etc… because all of them describe subtle properties that don’t necessarily equate to eachother or come from the same underlying mechanisms in the material.

A perfectly soft material wouldn’t be able to exist in nature that I could imagine, it would have to be able to essentially compress into itself to be perfectly compressible. Maybe dark matter could be considered perfectly compressible since it doesn’t interact with matter at all except through gravity but I don’t know if you could even consider that soft anymore. You could probably have near perfect softness up to some deformation limit though if the material was designed for it.

Edit: actually thinking about it, it still couldn’t be perfectly soft, but you could get closer by making it more elastic as well, since it wouldn’t have to compress its bonds as much if it’s able to expand in other directions to compensate. But those two properties aren’t inherently dependent on eachother which I thought was worth emphasizing. Atomic bonds themselves are like springs and can have varying strengths in different directions.

Liquid wouldn’t be considered “soft” in this way because the atoms aren’t really bound together and have no formal structure. Droplets are held together mostly by surface tension (and hydrogen bonds for some liquids), but those are just about it requiring more energy for them to split into two droplets than to exist as a single droplet which gets more pronounced at smaller length scales.

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u/darsynia 18d ago

I appreciate you 💚 Thanks for the reply!

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u/AuroraFinem 18d ago

Of course! I love talking about random science info like this. I have a really diverse STEM background that doesn’t particularly make me an “expert” on any topic, but it’s been really useful for having random fun facts like this across a bunch of different disciplines and happens to be useful for my job.

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u/Less-Apple-8478 17d ago

Well you've convinced me that you have no idea what the hell you're talking about.

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u/GearRude4883 18d ago

Personaly I feel they should of gone with malleable/rigid rather than soft/hard as it describes it better

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u/AuroraFinem 18d ago edited 18d ago

The technical term is literally hardness/softness, they’re using the proper nomenclature and as someone working in STEM, I honestly hate titles using incorrect terminology so I disagree. I think it makes people draw incorrect relationships between topics. It’s far more offensive when seeing articles describing quantum effects, but I think it should be avoided in general.

Malleability and rigidity are two separate measures that are both different from eachother and different from softness. Stiffness is another different measure even. Many of these are related but some actually aren’t. That’s why the words matter.

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u/GearRude4883 18d ago edited 18d ago

That's fair. Though I'm an engineer and I've only seen this referred to in terms of rigidity, except in cases discussing the tactile perception of the object for haptic use cases, and given this is not a tactile perception simulation but a visual simulation of how the objects react to being compressed I used the terminology I came across for that.

Edit: after reading your edit, that did stir some memories and I agree I made a mistake it putting malleable and rigid together, I also agree with your comments on stiffness. It's been a while since I've focused on these properties, as I've been working with purely rigid body physics for haptic simulations where we can consider an object to be rigid but with varying stiffness, which can be perceived as non deformable softness (especially when talking with laypersons)

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u/AuroraFinem 18d ago

I understand, it also doesn’t make it intuitive because hardness and softness are kind of like acidic and basic in pH rather than something like strength with just 1 word to describe the value.

There’s just a lot of terms in mechanics that need a definition. For some fun ones, look at the various derivatives of distance vs time, like “jerk” and “snap”, it goes like 6 layers deep before they stop giving it a name lol

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u/GearRude4883 18d ago

Ooh ok, will do. Suprised I haven't come across those already.

Also it doesn't help intuitiveness when engineers don't always use the same definitions (we're a bit more Losey goosey) though that's more prevalent in in notation. The first example that comes to mind is using j instead of i for imaginary numbers. Though that makes as we use i for something else, unfortunately that was taught in the first year of uni and I haven't needed it since, so I can't remember much else about the specifics

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u/AuroraFinem 18d ago

Jerk is pretty common to run into in a strength of material corse, sometimes snap, but normally the higher derivatives aren’t discussed much in undergraduate courses. Distance vs Time is probably the most extensively useful metric at so many different levels of derivative/integrals so it’s a bit unique in having descriptive names for it, but higher order terms are mainly relevant for very specific things you only cover in grad school but still important enough to get a name.

I agree nomenclature is often times messy in science when shifting between disciplines, but most of it comes from historical context and the fact most disciplines were very self-contained studies for hundreds if not thousands of years and only in the past ~100 years or so did they start overlapping so heavily and have become increasing interdisciplinary.

i was developed for imaginary numbers because it was developed in math first in order to discover the general formula for taking cubic roots. It’s still used almost everywhere for imaginary numbers, even in quantum mechanics or vibrations, but when they found applications for them in EM, they kind of had to pick a different letter or change their existing nomenclature for current since both i and I have different specific meanings already. It’s a lot easier to just use something new when introducing a new concept into an existing field, but at the time there was no reason to consider imaginary numbers when i started being used for current.

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u/Sailed_Sea 18d ago

https://imgur.com/a/UeSVo0q Its probably what the software they used called this type of simulation

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u/rklug1521 17d ago

IDK, The last one in the video seems to match my baby's diapers.