
Unreal Engine 5 Character Creation, Animation, and Cinematics
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Before we set up the IK controls, we need to get a few bits of information from our arm skeleton. This is going to be used later to set up the orientation of our IK control.
In the Rig Hierarchy window, right-click on the L_Arm_Lower bone and select Control Bone Transform, as shown in Figure 15.31:
Figure 15.31 – Control Bone Transform
This will display the local transform of the bone. Make sure it's set to Local Space and select Move, as shown in Figure 15.32:
Figure 15.32 – Axes primary and secondary
Notice that the Z axis (blue Z arrow) is pointing directly down the arm toward the hand. Note this direction down as +Z (if the blue Z-axis arrow were pointing in the opposite direction but along the same axis to the hand, it would have been -Z).
This +Z value is what we will use later as the primary IK axis. Now...