Root Motion: Where is left / right rotation coming from?

Question

I am using a generic animation on a generic character (coming from Mixamo).

The original animation does include root motion. However, the animation contains of a "straight forward" walk without any rotation.

When I use the animation on my character, the character makes weird right / left rotation, and I don't see where they are coming from.

This is a video of the original animation as seen in Microsoft 3-D Viewer: https://youtu.be/HWA53XhlGC8

And here is a video of how it looks in Unity: https://www.youtube.com/watch?v=odQBVkYnKw4&ab_channel=TW

Where is this rotation coming from? I don't see it in the original animation.

What could I check?

These are my import settings:

Thank you!

Answer 1

The reason why unexpected rotations with Apply Root Motion enabled happen on the character is that currently, it has no Root node defined. You can think of the Root node as the main driver of your character's Root Motion.

To set up the Root Motion properly, you will first need to select the character's FBX file in the Project window. You should see the character's Model Import Settings in the Inspector window. Select the Rig tab, and under Avatar Definition choose "Create From This Model". Next, select the Root node. Usually, the first one works, but depending on the way the model was set up, you might need to select a different bone to be the Root node. Click "Apply" and we are almost done.

Now, if you expand the character's FBX file in the Project window, you will see that an Avatar was created for this model. Select the character GameObject in the Scene Hierarchy, and drag the newly created Avatar onto the GameObject's Animator component's Avatar property. If you enter Play Mode in the scene now, you should see the character is walking without unexpected rotations.

I've attached some screenshots to help illustrate the instructions more clearly.