How to add two controllers on the middle of IK chain?+VIDEO

HI. guys here is the screen capture video of what i am trying to do. Please help me. I tried everything and my brain explodes. I cant figure out how to add those two controllers in the midde so they will move the chain. I tried for example to parent adjacent bones to those controllers but it will brake the IK chain which consist of 11 bones on three separated small chains which i dont want obviously. I tried also to give adjacent bones child or other constraints but it affects ik chain and make cycle dependencies or whatewer its called.

Its not possible to control a IK chain in the middle you can use ik chain bones as locators for hook control bones which control a spline ik chain…thats possible.


you can do something like this :
You can toggle the other layers in the properties. There’s a regular ik chain (yellow) with a pole vector, and three control bones (green) placed along that chain, and constrained by it (copy transforms). Then, three curved bbones (red) are stretched between those three control bones. There are also some helper bones (grey), because a bone with a copy transforms constraint cannot move, so I duplicated them and those duplicates act as the actual controls.

Btw, instead of bbones you could instead use other ik chains with their own pole vectors, or even ik spline chains.


Great. Thank you very much for this cool rig. I will use it now very often. Had to spend quite a while to figure out how this rig working. At first i was a bit shocked :)) because i found that you set chain length of the IK CONSTRAIN to 0, But the chain length was moving as it was set not to 0 but to 11. I never used IK constrain this way before (never set it to 0), so after some brainstorming i discovered that its moving because of the target and pole target regardless of chain length. After that all other things and parts of the rig becomed clear to me…I was close to something like this but i used copy transforms constraints or child constraints instead of Stretch To constrains, so because of that i couldnt move my controls. Now i see that Stretch to constraints are great because despite they are constrained to look at Cntrl tweak bones but you still can move them by using these Cntrl tweak bones which are parented to UTIL tweak bones and those constrained to IK chain.

But i also found that if i set chain length to 11 it still working same way perfectly, so i dont no why you set chain length to 0? Maybe you will explain to me the difference? Anyway thanks a lot for this!

By the way another way to do same rig i found whould be to replace three stretch to constrains with three IK constraints. And then just upper Cntrl tweak bones can be targets for IK (at the tip of IK bone) and bottom Cntrl tweak bones (at the tail of the IK bones) will be parents with offset for these IK bones.

Ah yes when you set it to zero it automatically sets itself to the total length of the chain, so 11 in this case.
ChildOf constraints are quite special and should be used (as far as I know) pretty much only with “detachable” parts in a rig, ie objects grabbed by the character, and so on. Yeah it’s a bit weird that one can’t move transform-constrained bones at all whereas some other types of constraints allow it. Anyway, as you reckoned the workaround is to duplicate them.