My goal is to rig the Ears of my quadruped character, which has huge and soft ears (rabbit-like).
I've set up a Spline-IK constraint for the ear's bones chain, and added soft body physics to the curve that control this constraint. Everything is working fine at this point.
Now, I want to give control to the animator over each individual bones of this chain, so that he can animate it the same way a basic FK chain would do, but keeping the soft body effect while playing back the animation.
Unfortunately, hooking the curve with empties will override the soft-body simulation for the vertices of the curve which are hooked (which seems quite normal). In addition, there is a dependency cycle because :
Curve depends on Armature through Bone Parent. Armature depends on Curve through Spline IK constraint.
I've tried several workaround (adding empties, separate the ear bones in another object...) but it always results in a dependency cycle, just with more steps :
Armature_body depends on Armature_ears through Copy Rotation. Empty depends on Armature_body through Bone Parent. Curve depends on Empty through Parent. Armature_ears depends on Curve through Spline IK.
So, my question is: Is there a way to add soft body effect to a bones chain, but keeping FK control over it?
Here is a .blend file at the state of my progress: Crastor Rig B.SE blend file