Using IK with two forearm bones

squatsch
Wed, 09 Nov 2016 15:41:04 +0000
World Creation

Hi all,

I am trying to setup IK for my character’s arms to be able to move the hands to any position.
Using the Two Bone IK node, this works well using Unreal’s standard human rig but not our character’s rig.

The rig we are using has two bones in each forearm, to be able to properly animate twist.

With this setup, the Two Bone IK node does not work anymore, since there are three bones in the arm:

FABRIK does not work either since it resolves the bone chain by ‘breaking’ the forearm:

Is there any way to prevent this, for example by ignoring or constraining the second forearm bone for the IK calculations?

Thanks in advance

6 posts - 1 participant