IK bone jumps to "random" location, and retunrs back when you click couple times on the rig

I subdivided 1 bone of the lip to have more control. And added a contoller bone for it (this small blue box on the right.
On each frame I have different pose.
When I switch the pose, this new contoller bone jumps into “random” location, even to there is no keyframe for it, and it should follow it’s parent.

Funny is that if I will be clicking on the rig “randomly” or selecting other bones, after couple clicks, this new controller bone retuns to it’s desired position. Even switching betweem pose and object mode for the armature does the same thing, contoller bone retunrs to it’s relative position to parent after couple mode changes.

Can anybody explain to me please why is this happening?

Ok so this is not happening when I disable bone constrains for this bone. But without these I can’t really use it.

  1. constrain is copy location of the right corner controller, influence 0.25
  2. constrain is copy location of the connected bone controller, influence 0.5
  3. constrain is copy rotation of middle lip bone
  4. constrains is copy rotation of middle lip bone.

If I disable constrain 2. this is not happening.
What is wrong with update of that constrain??

It is probably because you created a dependency loop. This happens most commonly with IK targets because the rigger (you) left the IK target parented to one of the bones involved in the IK chain, or a pole target parented to a bone involved in the chain.

In your case, your loop probably involves one of the constraints that you mentioned rather than parenting.

Occasionally, it happens because somebody sets the armature to use the ITASC solver, and that solver is totally bugged.

To diagnose dependency loops, you should open a console window from the main window menu and look for “dependency cycle” warnings.

1 Like

Hmmm, there is kind of loop but… I set this the same as previous controller, and that works.
this work fine →

this doesn’t →

lip.T.R.002 is the new controller bone.
lip.T.R.001 is the original I subdivided.

so lip.T.R.001 is trying to copy location of lip.T.R.002 - influence .25
lip.T.R.002 is trying to copy location of lip.T.R.001 - influence .5

Or maybe that’s the problem, as bone lip.T.L.001 on the other side, just copy location of lips.L (corner bone on the right side on the image) and just copy location of middle upper lip bone (lip.T)

Well, I guess you solved this :slight_smile:
Thank you!