How do you make realistic(ish) skin deformations?

I’m trying to make a rigid body character collide with a soft body character in a way that the soft body character has realistic(ish) skin deformations, but nothing seems to work. Cloth deformation is too extreme and effects the entire body, even when I make a weight map, and soft body just doesn’t do anything with rigid body. What settings am I suppose to use with these?

Wow no one knows on a site with this many people?

So…somehow no one in animation knows…no one in physics knows…who else would know about basic skin physics?

You’re going to get better answers if you ask a specific question ideally with a blend file attached so people can see exactly what you’re trying to do and what you’ve already tried.

“realistic skin deformations” is a really big topic so you’re not going to get a super simple “just do X” kind of answer.

I have to 2nd the comment above. The original question is not clear or precise enough. Its hard to know what to say or what advice to give.
From the little I can gather… All I can think is to perhaps try sculpting in and animating some shape keys for your impact deformation effect.

I’m not really sure how I can explain it any simpler. Something presses against say skin, the skin deforms right? That’s it, that’s all there is to it, I just want to know the physics (not rigging) settings to make an object deform like skin whenever another object comes into contact with it. A localized area of deformation should not use anything remotely resembling shape keys, I know there’s a way to do it with soft body or cloth physics, it’s just a matter of if a novice blender user who has a little bit of knowledge finds this thread.

Still waiting. Not really sure how so many particle physics are answerable but a simple soft body setup isn’t.

Waiting for? Godot?
Start with research on the matter. Almost a month passed and… ?
Here’s my 5 min.

fxguide: face study skin wrinkles
Animating Skin with Wrinkles Using Curvature Evolution and Energy Minimization

fold wrinkle skin animation

study face computer generated image muscles wrinkles skin

Different techniques for different approaches. Explore and educate self, know and choose your path…

… and if kind enough, please, show us your way.

Already researched it, literally no answers even though I saw youtube videos of it when I first started using blender a year ago. I’m not talking about wrinkles and I wouldn’t be here if I didn’t already google it, it’s rude to waste people’s time with your posts like that.

To be honest, I’ve never heard of anyone using generic softbody tools for this sort of thing. It’s always either shapekeys or custom in-house muscle/flesh tools. I think everyone in this thread is kind of just avoiding it thinking “I hope someone who has done this before will be along to explain what they did. I’ve never used it and can’t think of any time I’ve seen it used”.

Generally, you don’t want to use a sim for something you can accomplish without a sim. Sims are fussy, they’re slow to calculate, and they aren’t really purely accurate (because then they’d be even slower and more finicky than they already are). Like I said, some big vfx shop probably needed this for a shot and had their TDs add it to whatever muscle tool they use, but if it’s a one-off thing you need it’s probably easy to just do a shapekey and be done with it than spend hours configuring and iterating a simulation.

But a shape key strongly limits where and how a deformation can occur. If I have something like I cloth, I need every single point of the cloth deform like it’s cloth when a ball collides into it, not just one localized part where there’s a bone. I can’t think of any other way skin deformations could wholly occur.

If you are trying to get a Swiss-Army sim to handle all possible impact deformations, think again – you are looking at a terribly complex process, it is not just a matter of setting a few sim parameters and then all will fly like an eagle. Here’s why:

  1. Current sims act globally on a mesh to which they are applied. Localization is accomplished with tools like Weight Painting, Cloth Pinning and Soft Body Goal. Even then, the sim deformation is not localized in time, i.e., it will be a sim even when not being impacted, not such a good thing, since something like a punch in the face represents a very uncommon physics situation for skin & bone that is very localized in time. This is why Shape Keys are recommended – they provide time-localized deformations. They may also require more work, but that’s always a trade-off.

  2. It would be possible to time-localize sims using animatable parameters, but that would require a lot of testing to nail the effect. For example, animate the Soft Body Goals Minimum and Maximum settings to make an area on a mesh change its reaction to Soft Body physics, which along with Soft Body Goal weighting, gives you both a specific location on the mesh and a specific time for the sim to react. But be prepared to spend a lot of time developing the idea and pinning down the parameters (pinning pun intended). Maybe Shape Keys look better now?

  3. For “realistic” sims to work, you often need an unusually dense mesh (Cloth is a good example). But dense meshes can make regular animation problematic and will increase all sim and render times. They also put greater demands on your comp in terms of RAM and computation times.

  4. For all of the above reasons, a competent animator will be much more likely to use Shape Keys to produce the effects you are describing, in particular because they offer 100% control over the result, whereas sims can be, as mentioned, a li’l bit cranky at times. But Shape Keys also require that you know what the deformations should look like, which means studying the subject in depth. An animator should do this anyway, but it does require a commitment to the time and work involved.

Shape keys absolutely cannot carry out a holistic skin deformation, they are extremely limiting. Weight paint is an option but programmers forgot to tell blender that full weight means no movement, so all anyone needs for something like cloth deformation to work is extreme damping where they set the weight to 100, and that’s it. It would make something rigid where it’s suppose to be and leave a mesh clothy and flexible in other places.

Not quite sure what you mean by a “wholistic” deformation, but a shape key can certainly affect an entire mesh if that’s what you mean. Looking over your initial post I get the idea that you’re looking for a way to animate impacts between a hard solid object and a fleshy one. I avoid calling the latter “soft body” because that is a specific physics term in Blender. Just better clarity to say “fleshy” in this context.

So, hard hits fleshy. Impact is localized in both time and location on the fleshy one. If the sims are too inaccurate, a Shape key (or a set of keys) describing the impact seems ideal, as you can sculpt it exactly as you see fit, and control its implementation down to the exact frame. If there are subsequent impacts, more Shape Keys are generated. BTW, if a sim can get you close, converting that to a Shape Key and editing it to perfection is also an option. The only reason I can see for an all-physics solution is for real-time implementation, where the timing and location of the impacts might be arbitrary. But for a keyframed sequence, where the impacts are designed, Shape Keys just seem a lot more efficient and controllable.

Again, you’re not understand that I don’t want one ball to only hit one specific place, I want any ball of any shape to be able to hit any place and get a skin deformation without the entire mesh wobbling back and forth, having only a localized deformation from impact that dies out quickly over distance.

Regardless of how many impacts there are, each can be considered a single impact for the purposes of animating the fleshy mesh’s reaction. You just have to do it a lot!

Do you have control over where and how the balls hit? Are you spraying them at the fleshy mesh using a particle emitter or some such random source? That wasn’t very clear before & certainly changes the equation, but again, you won’t be able to get Blender’s sims to react as you wish because they are generalized, and your need is very specific.

Even if the source of the impacts is initially generated somewhat randomly, say by a particle emitter, if you bake the action of the balls so that they are repeatable over time, you can then map the impacts in time & location, making Shape Keys an option, even if it means creating a LOT of shape keys. If Soft Body Goal mapping could be somehow animated in terms of changing the Goal weights of specific vertices at a specific time, then it might present a workable method, but I don’t see how to do that with current tools.

Although… if a way could be found to animate vertex weights within a Vertex Group (which is what Soft Body Goal is), then time- and position-localized Soft Body implementation in multiple discrete areas of the fleshy mesh might be possible. I tried keyframing the vertex weighting in the Properties panel of the 3D Window but no go. Such an idea may be amenable to scripting but that is not my forte.

Old post I know… Take a look at the new Blender 2.8 Tiger video
The walk animation cycle is exported as an Alembic .abc animation cache. Then applied to a copy of the tiger mesh without Armature using the Mesh Sequence Cache Modifier to get the animation back without Rig. Then a cloth sim is applied. Weight 100% to the entire mesh. Then decrease the weighting in areas you want folds to occur. While in Weight paint use the smooth and level tools to get the folds to look nice. Then Mesh needs enough density to fold without artifacts. Also the Mesh Sequence Cache modifier only works off the highest subdivision at export. So you can’t add more subdivision on the copy, only on the export. What’s cool is you can test it realtime by press play and re-generating the sim each time you change weights. Enjoy

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