Rigging rounded open mouth

Hi. I try to rig an open mouth.
The corners of the mouth are not sharp, they are rounded.

My current Idea looks like this. (Simplified to a 2d side line drawing of an open mouth. Look Attachment)

If you run animation, you will see that the mouth opens and closes in a line.
After frame 75, the mouth is moved, the mouth corners are deformed.
(- edit … bone roll issue. corrected. Now it closes without side move -)

The mouth should close in a line. If you move it, it should keep its shape.

I would be glad if you have an idea how to solve this.

Thank you for your attention.

Attachments

Mouth_Corner_Close.blend (493 KB)

Ok … i found it myself.

Attachments

Mouth_Corner_Solved.blend (524 KB)

You can always fix weigh problem with weigh paint.

Or, with open mesh, among the three choices you get when you parent the bone to the mesh, you use “With Envelope Weights”. This method gives mesh assignment based on weigh envelop around the bone. It doesn’t matter if mesh is connected or it has holes in it.

Hi Ridix.

Sorry. I should have said more.
I like to do lip deformations with lip bones.

( Here it is rather not a weight problem between head and jaw. Lip weights are on lip bones. )