It sounds like you are experiencing issues with head tilting in your rig. Based on the information provided, here are a few potential solutions:
Check for Non-Uniform Scaling: Ensure that you are not using non-uniform scaling (where scale X is not equal to scale Y) on the head's parent bone or any of its parent bones. If you are, disable the "Inherit Scale" option on the head bone to prevent distortion during rotation.
Transform Constraints: Use transform constraints to control the head's movement. This allows you to have more control over how the head moves in relation to the body. You can turn the constraint on or off depending on the animation needs, such as when the bird pecks the ground or when the head moves independently.
Bone Weights and Mesh Deformation: If the head is part of a mesh, ensure that the weights are properly assigned to the bones. This can help in preventing the head from distorting when it tilts. You can also use a bone that moves in the opposite direction to counteract any unwanted movement.
Simplify the Rig: Sometimes, a simpler rig can be more effective. Ensure that the bones are aligned correctly and that there are no unnecessary bones that could complicate the animation.
Check for Keyframes: Make sure there are no unintended keyframes on the head rotation that might be causing the issue. If the problem occurs in only one animation, try deleting the head rotation keys and redoing that part.
Here are some useful resources and examples that might help you further:
If you continue to experience issues, you might want to review your rig setup and ensure that all bones and constraints are correctly configured.
