Rig Spazzing out

I have an issue setting up IKs, I followed Nathan’s Humane Rigging courses, but still…

When stuff like this happens:


And it leads to stuff like this:

you can stop laughing now :slight_smile:

I have no clue how to solve it, as I am 100% sure I set it up correctly, shift selecting bones and [shift+I] adding the IK. Then setting IK lengths to 3 or less but never 0.

I don’t understand where a cyclic dependency could appear in this way.

And as you can see, just rigging a FOOT goes awry :_(

I would really appreciate some help on this issue.


UMA_Animations_IK_setup.blend (1.88 MB)

The IK target cannot be a child of any bone in the IK chain. Certainly not a child of the bone that’s targeting it. That’s your cyclic dependency. It needs to be a child of something above the leg in the parenting hierarchy. I usually parent leg IK targets to a root bone that sits at the base of the armature. The root bone is the ultimate parent of everything in the rig. In your case I suppose that would probably be the bone you’ve named Global, but I haven’t examined all the parenting enough to be sure.

Thanks K Horseman for the quick reply :slight_smile:

IF I understand correctly in this case, the toes should be a child of global and not of any part of the leg?

If you’re going to use the toes as the IK target, sure, but you really should have a dedicated IK target bone rather than using a part of the anatomy as the target.