Root bone issues

Hi, Picture a monkey climbinga a hanging wire, hand over hand, then take away the body, so only arms, the bone structure goes from on hand to the other.
The root of the armature will be in one of the hands.
It is easy to animate the first “hand over hand” motion, but when the “Root” hand need to move over the “free” hand/bone then I am struggeling.
Is there a way to animate this without messing up the animation?

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So let’s say hand.L is current root. Make a new bone “root” at location of hand.R, duplicate that bone. Duplicate gets named “handP.L” and placed at location of hand.L. Do not change orientation of handP.L-- it’s essential that it’s oriented in the exact same way as root. Give handP.L a copy location constraint, local->local, XYZ inverted all, targeting root. All bones inherit rotation.

When hand.L lets go and you want to instead rotate about hand.R, snap cursor to hand.R, snap root to cursor, and see what happens: handP.L inherits location from root, then exactly counteracts that location with its constraint, so nothing appears to happen. Now rotate root and notice what happens. HandP.L rotates about root, so hand.L rotates about root, and since root is at the location of hand.R, that appears to rotate the entire skeleton, up to the point that it depends on hand.L, about hand.R.

Hi, thank you for your answer, but I am having trouble replicating what you are writing. Is it possible for you to make a quick blend file showing me what you mean?

Did you have any luck? I’ve been trying this for hours and running in dependency loops all the time. I kinda need to know this now :smiley:

Not yet unfortunately, I am still trying to find a solution. :thinking: Hehe me to :face_with_monocle:

Sorry, I didn’t think it through all the way. Structure doesn’t have dependency issues, but not good for what you’re doing (180 degree rotations get reinterpreted.)

I might play, and if I find something good for you, I’ll let you know.

I know it’s an addon and all but this one is really nice and let’s you change the root bone on the fly so it’d be great for your climbing monkeys-

Was playing with it and I like the approach a lot - might not be everyone’s cup of tea, if someone is used to fk/ik switches and likes the way they work. I sure won’t miss them :).

Hi, I also asked on “blender.stackexchange” and got an answer that might give you som inspiration: https://blender.stackexchange.com/questions/144464/animation-root-of-armature
What do you think?

Hello :slight_smile: I have downloaded this addon and I will try and see how it works. Thank you for the tip!