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Root motion issue using mixamo roll animation

Hi ! (sorry for my english, i’m french)

I’m a bit new on Unreal Engine 4 and i’m trying to make my character rolling when i press an input, so i used a Mixamo roll animation combined with root motion and it work perfectly.
But the thing is that when the animation end, my character doesn’t return to his basic rotation.

(Screen is better than words)

How can i fix it ?

Thanks you and merry christmas !

I suspect that your character doesn’t have a “root” bone.

“Root” bone is usually located at character’s feet (point at the ground where character is standing) and “hip” bone is parented to that.

I think in your case character doesn’t have a “root” bone, so when it rolls it actually rotates collision capsule, and when animation ends capsule gets stuck.

Might be wrong about it. Not having a root bone is a fairly common problem with mixamo characters.

Oh i see, yes it should be that, how can i fix it ? Edit the rig using maya ? Or simple use the Ue4 Mannequin skeleton ?

Edit : Indeed, it’s the root bone problem, my capsule gets stuck.

You’d need to edit the rig in maya or whatever is available to you, add “root” bone to it, and then properly transfer animation somehow. If that’s mixamo animation, you should be able to upload your char to their site, apply animation to it and download it back. When character already has a root bone their retargeting service should transfer root movement properly.

In this case, it might work, since the roll animation is not going up in the air. However the automatic generation of the root joint done by Mixamo causes the root to get some rotation applied from the projection on the the ground plane. This can cause issues. I have personally done the fix for Mixamo animations and root motion by using their normal FBX download option and then adding the root manually in Maya and then copying relevant keys from the hip (which is the root for Mixamo) onto my new root joint.

If this doesen’t make sense, i’ve made a video showing the process here: Part 1 - Howto get Mixamo rootmotion into UE4 - YouTube