Skeleton Mesh deforms after Animation Retargeting

Hi Question Hub

Link to the video that shows the problem.

I am stuck on an issue with Animation Re-targeting. I’ve gone through Animation Retargeting (Different Skeletons) and Animation Retargeting(Same Skeleton). I’ve also watched the Zak’s YouTube videos on animation re targeting.

For some reason, the forearms on my skeleton mesh deform when I re-target animations from Mixamo. Here is a short video that shows and explains the problem in detail. I can’t work out the answer, the skeleton itself looks OK. The animation is set to skeleton, most of the mesh fits fine - except the fore-arms. They deform and bend away from the hand and I can’t work out why. I’ve tried to experiment with re targeting poses but that didn’t produce any meaningful outcome either.

If anyone can help, it would greatly appreciated.
Thanks !

I don’t know if this would solve the problem, but here are a few options:

  • the weights of your skeletal mesh are off, so you would need to go back and repaint/blend those weights
  • the proportions of your target skeletal mesh is very different than your source skeleton.

you might want to try working backward, export the source skeleton out into a 3d package, then try skinning your mesh to those exact bones. Then re-import that target skeletal mesh and try retargeting. If that doesn’t work, i would recommend using IKinema () or Motionbuilder for your retargeting.

in my honest opinion though, i honestly think it’s a skinning weights issue.
hope this helps

did you figure this out? i have the same issue! thank you.

Hello -

In case you are still trying to solve this (one year later), here is something that you can look into :

The default Epic Male skeleton has some extra “twist bones” in various places - legs, shoulders, wrists. These can sometimes be used to counter-rotate areas that might deform too much on a model when in extreme poses. However, most third party animations (Mixamo, mocap) converted to the current skeleton will not drive these bones.

Your video seems to show that you somehow ended up with an animation asset that does drive these bones, but in an unintended way. So the first thing to do would be for you to look at the skeleton tree, locate the forearm/wrist twist bones and rotate them to see if they do indeed cause this floating wrist deformation. From there you could then look into finding a way to prevent that. These twist bones probably received some unwanted data from the retargeting process, so it is very likely possible to fix by retargeting the animation once again but this time making sure that there is no data retargeting going on towards the wrist twist bones at all in the retarget manager.

Good luck !

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Thx man … Save my day!