Hand/Arm IK with some rotations.

Dear Forum,

I am looking at supplement my two bone IK box with rotations for the elbow & shoulder. Ideally I would like the hand bone to be the anchor.

Currently I’m using two bone IK box (Or FABRIK box) and feeding in the desired position & rotation I want to hand bone to be in. So far, far good. However I want to additionally add in rotations on top of the two bone IK or FARIK for the shoulder and elbow. I would like the hand rotation & elbow rotation to be the same (which should make things easier) but just can’t seem to add the appropriate boxes to get good looking results. So the movement is around the hand bone.

I looked at the Leap Motion plugin anim graph for inspiration on how I could achieve this since that is what I would like. E.g when I roll my wrist the rotation of my forearm in UE doesn’t change location but rotates the arm in space.

Attached is a section of my anim graph. I’m rotating the forearm then the upper arm before applying a FABRIK box. This seems to kinda work but I get weird twisted angles in the elbow and shoulder. I’ve also tried using other boxes like “Copy Bone”, “Look At” and “Bone Driven Controller”.

This is probably something which is easily done I just wanted to ask the forum to see if anyone had points for me.

Many thanks,

Peter

I guess knowing where the elbow is would help too.

Hopefully Epic includes rotations in their two bone IK box soon.