Objects in Blender not following/rotating correctly in Unity Avatar config

Help!
1

Hello!

I am new to Blender and Avatar creation. My current project was making a character from a game into a VRChat avatar. I ported the model to blender and rigged it myself. The thing about this avatar is that the eyes and mouth are technically 2D and have their own separate meshes. I have them parented to separate bones that are then parented to the head. I have weight mapped all pieces of the different eyes and mouth as well. When putting the model into the Unity scene, the meshes for the eyes and mouth are moved forwards a little bit than their resting position in Blender.

When I enter the config, the eyes and mouth that I have showing on default are moved slightly lower than they are supposed to be, and they don’t properly move with the head. I have been stuck on this issue trying to fix it for nearly 2 hours. I’ve tried applying transforms and joining meshes, but nothing will fix the issue.

Any kind of help would be much appreciated!

EDIT: All the meshes for the eyes and mouth are following the movement of the spine but not the head. Yes I have checked the meshes parent bones and it is NOT the spine. They are parented to their own individual bones that are parented to the head. I tried to change vertex grouping when weight mapping and that did nothing. I have also tried to change the vertex group in the modifier and now I cannot see the eyes nor the mouth of my avatar even when reverting the changes. I’ve also noticed that the picture of the armature in Unity has the meshes for an accessory on the model AND all the meshes for the eyes and mouth. I don’t know if it is supposed to be that way or if there may be an issue there.

I have images to better show what I am talking about -

Here is what the model looks like in Blender -

image_2024-11-27_234220746
image_2024-11-27_2342207461009×878 318 KB

How avatar looks in Unity’s Avatar config -

image_2024-11-27_234257491
image_2024-11-27_234257491389×402 118 KB

How the face moves with the body when tilting the head -

image_2024-11-27_234352166
image_2024-11-27_234352166389×307 81 KB

2

Hopefully someone with more knowledge chimes in but my un-educated guess would be a issue with the weight painting?

3

I have them all weighted correctly to their parent bone. I’ve sesrched up the issue and looked at Blender forums as well to try and find a possible issue. :sob:

4

Hi! I wanted to reach out to you again and let you know that I found a way to get only ONE of the mouth meshes to work correctly. I was messing around with the vertex groups within weight maps and checking them all over again. I made a vertex group for each individual mesh and the mouth piece that worked correctly actually moved during the weighting process which the others did not do. I’m trying to find out what is different about this mouth mesh that makes it work correctly in unity and I was wondering if you maybe had any ideas?

5

Hmmm, I’m afraid from scratch is not really my realm I know bugger all about blender, are the eyes parented under the head in the bones?

6

The eyes are not. They are parented to their own bones. Those bones are parented to the head.

7

That should be fine vrchat wants to see a very specific bone layout but if the eyes are under the head bone then this should be fine. If you move the head inside the scene does it leave the eyes behind still?

8

Moving the head inside of the scene shows all of the eyes and mouths. The specific mouth that is working is in the correct place while all the others are oddly placed further out.

image_2024-11-28_234633406
image_2024-11-28_234633406351×284 146 KB

9

Uppon closer inspection D3m0nH0uR accidentally assigned the eye bone to the chest of the avi, so when the head was moved the eyes stayed with the chest.