Physics Jitter when attaching a static mesh to a ragdoll bone (collision off)

Hello staff @ Epic. I’m having an issue using the unreal engine 4 v4.8.1 but to be exact all the previous versions show the same problem so it’s nothing to do with the version, i think.

When i attach a static mesh to a skeletal mesh with physics enabled, and simulate, or play, the static mesh just wobbles around and is not perfectly “attached” if i might say, to the bone socket. I have made a demo so you can check it out for yourself, Download the demo project here: [][1]

(During Play test press F to enable the physic simulation on the head bone, then move around and look at the mask. I couldn’t make the project smaller than 17mbs, even though there’s nothing more than the very basics inside, Sorry about that.).

If you can’t, or don’t want to download, you can get the same results by opening the third person character BP, attaching a static mesh to the player character’s head bone and enable physics on the head bone, then walk around. The static mesh sorta feels wobbly and is just unrealistic if used in a game with ragdolls.
(It has to have physics enabled, so it has to be a ragdoll. It works fine if the skeletal mesh is animated or immobile.)

Thank you for your time.

Please regard into this issue, we can’t progress further on our project untill this is fixed or has a work around :frowning:

[1]:

Hi ,

So the issue that you’re reporting is that the goggles attached to the player’s head aren’t quite sync’d up to the head’s movements with physics simulation. Almost like they are sliding around on the head? Just confirming.

-.

Yes, that’s the issue. Kinda weird.
Same thing with non-player skeletal mesh physics simulation.

Hey ,

I’ve spoken to some of our engineers about this and have entered this issue into our system as UE-18122. This is not expected to occur when you have “Weld” enabled for attachments to components/actors with physics enabled. I’ll keep you updated on any further developments.

-.

Alright then, I’m just going to attach my meshes together in maya for now .
I hope this is fixed in one of the next updates then. Thank you for your time :slight_smile:

It looks like this won’t make it into any hot fixes for 4.8, but you can find the fix here in Master Branch on github. You can integrate this change yourself if you’re using a code project. This fix has not been verified yet, so it might not work. However, if you’d like to get out ahead and try it, you can.

-.

Hi again, sorry for the late answer but the link doesn’t work. :confused:

Hey ,

I noticed it wasn’t working for me either, but it appears that you have to sign into github before it will let you visit the page.

-.

Has this bug been resolved yet?

I think I am having the same problem atm.
Got two seperate actors that simulate physics. When attaching one of them to the other, I deactivate the “Simulate Physics” of the attached (now child) actor.

When in playmode and moving the parent actor (which is still simulating physics) I got this strange wobbling, as if the movement of the parent aren’t synched to the attached child.

Is this a known bug, or am I just too newbie to solve this on my own with some settings?