Problem with IK bone

Support Animation and Rigging
1

Hello everyone,

Introduction: I am taking a rigging course because my knowledge of the subject is extremely basic. During a lesson, I encountered a problem that I cannot solve and I would like to avoid doing it all over again to understand the reason behind it and avoid making the same mistake again in the future or just be able to solve it.

Problem: After disconnecting one bone of the rig (foot) to move the leg, I made an IK constraint to animate the movement of the leg which is composed of two other bones. But when I try to move my foot with G, the chain goes crazy.

The relationships starting from the bottom are: foot ->leg bone 2 ->leg bone 1 ->body bone.

Below is the video of the problem, thanks for any suggestions.

2

Check the parent of the tgt_foot bone. What you have is called a ‘dependency cycle’.

With the foot being a child of the leg, but also wanting to position the leg with IK, each one is trying to set the position of the other one.

In the video ‘04_09 Spider ball Leg rig’ at around 03:55ish, he clears the parent on the target bone before setting up the IK constraint.

2 Likes