Rigging question

I have a situation. i have a model and i want to rig it. But, his eye brows are ones i have separately done and rigged to the point of success that i wanted. So, changing that or recreating that is out of the question. What i want to do is parent/link the eyebrow rig to the metarig/model-rig in such a way that the eyebrows work on their own, but when i move the character through the humanoid rig, and move the head, the model & rig of the eyebrows move with it, without disrupting or disfiguring the eyebrows. i know that it is something you can do, because i’ve seen animation that surely have separate rigs within rigs, but I’m in a conundrum of making the same mechanism myself. Any help or suggestions on the matter will be greatly appreciated.

As long as your eyebrows have a ‘base’ bone (a parent at the top of the hierarchy of bones), after generating your Rigify rig (I’m assuming that’s what you meant when you referred to a ‘meta-rig’):

  • in Object mode,
  • select both rigs (select the Rigify rig last),
  • Ctrl-J to joint them,
  • make all rig layers visible (either one at a time or all at once) so you can find the DEF-head bone,
  • select your eyebrow rig’s base bone,
  • select DEF-head,
  • Ctrl-P to make the eyebrow base bone a child of DEF-head.

Everything should be fine from there.

Of course, I’ve left out aligning the meta-rig and setting bone weights, but there are several video tutorials around for that.

Thank you very very much. I will apply these methods as soon as i get the chance to.