Control rig crazy jittering and not moves at intented direction


Hi guys, I have a problem regarding the control rigs behavior
I use UE5 mannequin, add FK controller to pelvis and thighs, and IK controller to limbs

However, the behavior of the control shape is wierd

Background: I set the control rig graph like this: FK on pelvis and thighs first, and then set FARBIK for all 4 limbs, and spine

Problem1: When moving the IK target shape, it starts crazy jittering affter moving for a few inches, which makes it almost impossible to position it precisely over an object.
What’s more, after moving it for a long distance the IK controller will move out of the controlled bone, and when you rotate it, the actual limb’s tip will be rotating around a fly-away or off-position axis



When the IK controller is off the bone, it will moves more than the tip bone that it affects.

Problem2:Then the FK controller does not work as expected. You see if I use move mode on the thigh FK controller, when I moves my mouse and select an axis of the gizmo, the controller does not move along the selected axis, infact it goes in its own direction. It sometimes happens to pelvis bone and its controller, sometimes the pelvis controller will move more than pelvis bone. When I rotate the pelvis FK controller 90 degrees, the pelvis bone only rotates 45 degrees; when I move the pelvis FK controller 100 units, the pelvis bone will only moves 50 units.

How does this happens?
Is there anyway to accuratly position hands/feet with IK?

Hey did u manage to solve this? Im facing the same issue :confused:

I figure it out on my case was because I was using the controller as Child of the bone and trying to move to bone with the controller, was a mistake in the way I created the controller. It should be created trough “add controls for selected” that way it creates the correct hierarchy structure outside the rig.
As I said I was using the control as child of the bone that was causing some redudance jittering hope it helps!

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Hey could you send a picture of your hierarchy? I’m having a similar issue but i cant figure out how to set it up. The tutorial i was following keeps having me child it to the bone and for some reason it works fine for them.