Independent Bone but Also Connected?

There is probably an easy solution to this, but my Google searches came up empty. Probably because I don’t know how to phrase what I need.

I’d like for the helmet to be independent from the rest of the body, but also have the ability to stick to the head bone.
This would allow me to have the character take off the helmet, then move her head. Right now, the helmet always moves with the head (it’s parented to the head bone).

I tried to solve this for hours using bone constraints but couldn’t get it.

I’m attaching some screenshots showing how the rig works right now. In image three, she should be able to tilt her head back up, but leave the helmet in her hands.

you have to animate the constraint influence. Somthing like make the helmet bone have no real parent (what you term as independent) but have a “child of” constraint to the headbone. When you want the helmet to follow the head, set the influence of the constraint to 1. When you want the helmet off, set the constraint influence to 0

I actually tried exactly that, but I had the helmet bone parented to the root bone. I keyframed the bone constraint with full influence when the hands are out, head over, helmet out (image 2 above), then removed the influence to make my next keyframe and the helmet moved back to it’s non-transformed location. I would need it to stay in the characters hands, remove the bone constraint influence, and then insert a keyframe… which I couldn’t do. What am I missing? I knew I was close to solving it, but I couldn’t get it.

toggle the “clear” and “set inverse” buttons on the child of constraint

I started fresh with a new bone constraint, and also set the helmet bone to have no parent. When I added the constraint, I ran into a new problem. If I understand this bone constraint, both images should be the same (I set the influence from 0 and 1). Since the head hasn’t moved between images, the helmet shouldn’t move, right? For some reason it jumped forward and rotates 90 degrees.

If I toggle “set inverse”, the helmet location is corrected, and all is well. But, if I clear it, it is ruined for every keyframe in my animation. So, I didn’t clear it, and but when I remove the influence, the helmet does not keep it’s location. That keeps me from making a keyframe for it. Here is a close look at what’s happening for me…

alternatively you can have a bone permanently parented to the hand, and another permanently parented to the head, and the helmet bone with copy rotation/location constraints to both. Animate the influence from 0 to 1 and the other from 1 to 0 to switch between the two

That wouldn’t work for me. This is just one animation. I want the ability to put the helmet anywhere, without the rest of the rig influencing it (e.g., the helmet being knocked off and falling to the ground). But also have the helmet locked to the head when it’s on.

then set the influence of all constraints to 0

I’ve tried, without success. Anyone else have a suggestion?

no-one has any other suggestions because the valid way of doing it has already been pointed out…

have the helmet bone use no parent (or root parent), then “child-of” the helmet bone to the head bone.
click “set inverse” and key the influence at 1…
then move the hand (I would be using IK but either IK or FK should be fine) to the point it will grab the helmet…
once its at this contact point, add another “child-of” constraint, constraining the helmet to the hand…
click “set inverse” on this new constraint and key the influence at 0

now… the helmet will follow the head… when you want to “remove” the helmet, set the “head bone” constraint to 0 ,
and the “hand bone” constraint to 1… if you want to “put down” the helmet, simply set BOTH constraint influences to 0

this is the approved way of doing it :smiley: Of course, you needn’t even use a helmet bone, you could use regular constraints in exactly the same way for any object type.

Okay. :slight_smile: I will work with it some more and see what I can come up. I haven’t got it to work yet, but I do appreciate the help I’ve been given so far. I’ll reply with me results!

Success! Although, I had to do something unexpected. When I changed the Child Of constraint from the Head bone to the Hand Bone (in my rig, it’s arm.L.2) the Helmet location and rotation is thrown off. I just repositioned it manually. Here’s a video clip of the animation running:

Thanks again for all the help!