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Please help me to understand how physics and skeletal meshes work

I understand that one can add a physics asset to a skeletal mesh, so that when physics simulation is enabled for this mesh I can do things like ragdoll simulations. Ok, fine. Now when I have a, say, humanoid skeletal mesh for an actor, which has physics simulation enabled. The actor/mesh is standing on the ground. What is necessary for me to do so that the mesh does not fall down to the ground due to gravity?

In other words: In reality a dead human body would also fall down to the ground when you stand it on its feet. But since in reality we have muscles, we can still stand upwards. But in UE4 I don’t simulate these muscles, only the bones and physics bodies. So how can I make the character stand upwards, even with physics simulation enabled?

Good question actually. You could possibly make something like this using a combination of the Linear/Angular Damping settings, and the joint motor settings…but I’m not sure exactly how.

If you’re looking at the character in the physics window then I’m pretty sure you’re just looking at the ragdoll for purposes of designing the physics asset. If it’s in the level then you’re probably just placing a ragdoll and not an actual player or pawn. You need a blueprint associated with it to do anything other than look at it and you have to apply an animation to get it to do anything. In other words if you apply the ‘idle’ animation to a character with the appropriate blueprints, place him in the level and hit play - he will stand there idling. If you drag a rag doll into the level and hit play he will just fall because that’s what ragdolls do. When your character dies you generally destroy the character with the blueprint and replace him with the ragdoll.

Well, what you say makes sense. However, what I don’t understand is how physics and animations work together. I saw in several threads here that one cannot use animations and physics at the same time, it’s either animations OR physics. Or do I missunderstand that? In the 3rd person template for example the main character also has an animation applied, but physics turned off.

There is a capsule around your character that does collisions while the character is alive, that keeps you from walking through walls etc. The ragdoll thing is more for when you lose control of the character - death (or if you wanted to hang a pawn from a hook and have him swing). You would not be using that during an animation.

I see, yes that is how I understand it now as well.
Thanks for your help!