Can IK joints affect animations negatively?

Hello all, thanks for taking the time to check out my question.

I’m animating a basic idle and so its movements are more subtle. I am exporting directly from Blender and to the animation editor.

For an unknown reason, the bones are “Snapping” or “popping” rather quickly in the Roblox studio animation editor whereas the blender animation is smooth.

Edit: More info:
It only happens when the root (Pelvis) bone is moved.
I only have IK restraints on the knees.

Could my IK joints be affecting this?

Any help appreciated.


I use IK constraints for both my legs and arms in my rig and I have noticed problems like this. It doesn’t always happen, but it’s caused by the .fbx file keying every bone to every frame (to essentially bake your animation’s transitions/easing/interpolation). You probably only have keyframes on a few frames out of the whole bunch in Blender, but when you import to Roblox it puts one to every frame. So look at which ones you do have in Blender, and delete the rest in Roblox as they aren’t needed. Then tweak your easing and interpolation in the animation editor.

I might be wrong on some of this, but it’s worth a try.


Thank you so very much! I would have never considered doing that! It works!

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