Reply To: IK Rotation Not Working after Linking in and Making Proxy

Forum Archive IK Rotation Not Working after Linking in and Making Proxy Reply To: IK Rotation Not Working after Linking in and Making Proxy

#51813
Phil Osterbauer
Participant

    Hey Blenderguy15,

    I know the flex rig isn’t really optimized for Blender 2.8x and I’m not sure if it will be. But I can give you my theory on what is going on and how I fixed it.

    The IK solver in the leg needs a clue in what direction it wants to bend. Usually when in edit mode of the armature you would want to put a slight bend in the knee in order to provide that clue.
    Nathan Vegdahl was one of the creators of this rig. He also has a rigging course on Blender Cloud and YouTube called “Humane Rigging”. There he teaches a technique where you could keep that IK chain straight, then put a slight bend in the mechanism bone in pose mode and that would provide the clue to the IK solver in what direction to bend the knee. It worked in 2.5 up to 2.7x. For whatever reason I don’t think that technique is working in 2.8. I could be wrong, I haven’t ruled out everything but its what seems to stand out the most to me.

    To solve it, tab into edit mode on the armature and turn on all the bone layers to unhide all the bones. Then take the heads/tails of all the bones at the knee and move  them forward to introduce a slight bend. There are 2 bones that lay on top of the thigh bone and 2 bones that lay on top of the shin bone that will  be misaligned slightly. You can move them forward as well to stay in line with the thigh and shin bone. Now when you link the rig to another scene the knees will bend the correct direction toward the pole targets. I hope this helps you, feel free to ask questions if you get lost. 

    Happy animating (rigging)!