Moving Component with Attached Physics Asset Updating Bug

Hello,

I am currently working on ragdoll physics and how to blend from the physics back to animations.

Normally when blending from physics back to animation the skeletal mesh moves back to the capsule. However, I want the capsule to move to the mesh. So every tick when I blend back from the physic to animation I look how much the mesh moved back to the capsule and apply this movement in the opposite direction onto the capsule.

Here is a screenshot of the blueprint:

This solution works pretty good and the capsule moves to the mesh. However, the mesh still moves a little bit towards the capsule and then moves back to the location it was before.
The “get socket location” also returns a different value than where the socket is actually rendered (the value it returns is the location where the socket should be (means the “get socket location” for the root value stays at the exact same place)). Attached meshes also behave like they should (and like the main mesh should). For example if I attach a mesh to a socket / bone on the mesh, the attached mesh stays exactly in the location where I want it to, but the main mesh still moves a little bit to the capsule.

Here is a video of the problem: (sorry for crappy quality - I have an upload of 10KB/s max so I had to compress it really much)

I am working with slow motion there so it’s easier to see. I attached some meshes to certain sockets and as you can see when I blend back to animation and move the capsule to the mesh the socket attachments get updated like they should but not the main mesh.

So is this a known bug? Is this a bug? Is there a workarround?

Best Regards,
Joey

Hi dj_joey,

I attempted to reproduce your setup but I’m not getting your same behavior. Could you create a small test project with the issue and post a link to download it here?

Hi TJ,

here you go: Dropbox - Error
Took a while to upload…
It’s a new project with the default guy.

F is Toggle Ragdoll
T is Slow Motion for better visibility

When Disabling Ragdoll the capsule gets pushed to the mesh the same distance the mesh pelvis moves back to the root which has a fixed position.
Every tick I draw a debug point at the pelvis location. You can see that the pelvis is not where the point is drawn.
Also the gun, which is attached to the hand is not where the hand is (Or better said the hand isnt there where the gun is)

It’s best visible if you get the ragdoll as far from the capsule as possible → enter ragdoll while jumping in some direction. You will also see another thing I don’t really understand. Why is the mesh not rendered anymore if the rootbonebody is not in frame? Is this a bug or is there an option I didn’t check.

Best Regards, Joey

Hi dj_joey,

I just wanted to let you know I’m still looking into this. I’ll let you know when I have more information.

ok cool thanks :slight_smile:

Hi dj_joey,

I was able to reproduce this and have entered a bug report, UE-19218, to be assessed by the development staff.