Null bones for char anim

I’m doing a char anim and I ran into null bones being mentioned here:

I’m not sure what they are but what I do, instead of creating an “empty” object and controlling the anim from the object mode I figured out that if you create a new armature bone then position it to your skeleton where you want it, you can then join the new bone with the existing skeleton and thus bring your IK control bone to the same space ie. pose mode as the rest of your skeleton. The skeleton I’m talking about here is formed from one root bone and spreading bones in all direction from that root bone. So in pose mode you can only move root bone but can rotate all others. Is this IK bone that I created called the null bone or is there a specific null bone object in blender I’m unaware of?

Ok, just wanted to mention a method that will allow you to move your non-root bones in pose mode with this control bone. It’s important that you join it to the existing skeleton to bring it into pose mode. Join, I mean Ctrl+J in object mode. You will have to create one extra bone by extruding your end bone(in edit mode) in the bone hierarchy to tie this IK control bone to otherwise this new bone will snap to the wrong location of the existing bone of the hierarchy. This hierarchy is made like this ie. steming from root bone so I can import it into my game engine and move the root bone and have all bones move with it. For blender only anims, you don’t have to do it like this and can instead create separate skeletons that you can then move/rotate freely in pose mode.

phew, hard to read, your post! kind of too long sentences… null bones are bones that don’t actually deform the geometry (but in the end regular bones, no special objects). null bones are helpers and only used as constraint targets, i.e. IK, stretch to or copy Rot/Loc. null bones can reside in the same armature as the “driven” bones, or they can be in an other armature. they can also be substituted by any kind of objects, but then you lose the ability to animate via NLA.

hmm. Keep on at it, you’re discovering pretty much standard practices in rigging.
As to null bones, you can call any non geometry controling bone a null, sometimes an IK solver and sometimes the end of the ik chain (personally, I name the end of the chain null, unless it has geometry attached, and the solver, goal)
In some packages you can make a bone that looks like an empty- it doesn’t have a tip, used in the above situation as a goal. It doesn’t add functionality, it takes it away, but reduces visual clutter. These apps might call this bone a null or an empty bone.

yeah, but I wouldn’t make the bones from the arm all the way to the hip one unbroken IK chain
would be tough to animate.
you could have
upperarm->lowerarm->hand as a chain
and handtarget as an IK solver for hand
hand in this case is the “null” but it also gets verts assigned to it.
with an IK solver for handnull
not sure if this helps or not…

I deleted my post now that I’ve experimented with rigging and my question was answered.

Yes, I break the IK chain, actually blender did that for me. It’s when you extrude another bone from the bone’s basis that the IK chain is broken automatically. Like when creating a neck bone then extruding left and right shoulder bones from neck bone’s start point or basis. Thanks for your thoughts.

Edit: I parented my mesh to the skeleton and then I added in the extra null and IK control bones so that extra vertex groups aren’t created for those special bones.