Hello,
I am an issue with Lamp Stem’s constraint. When I use Look to control the lamp, the Lamp Stem moves X and Z which I’ve constrained them already, and Y is unconstrained. I couldn’t figure out the problem.
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Do you use IK?
And is the length of the IK chain -1?
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Yes, I use inverse kinematics and chain is 4.
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-1
Need to be three I think!
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I have an experiment with inverse kinematics. Why is the bone constraint not working when I apply IK? the bones are moving through themself.
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- Did you use length = 3 for 4 bones?
- Did you add bone restrictions for the bone rotations?
if I use 3 chain then the bottom bone won’t move at all. Yes, I use the bone constraint to restrict bone rotation.
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That is correct. You need to connect the bone to a parent something (like an empty, or lamp base_.
Adding restrictsing is hard to do, because of the 360 rotation minus/positive trurns and local world coordinates. A lot of things can go wrong. Check everything.
Start small using two bones. expanding the chains.
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But with BONE CONSTRAINT, the bones are not suppose to move through themself. And the bottom bone should move rotating Y axis, not X and Z.
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with 3 chains, bottom bone not moving or rotating Y axis.
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It seems the IK is override the BONE CONTRAINT, when I check the individual bone constraint movement, it works. But when I use control bone (the cone) everything is not working. How can I fix this problem?
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Unsure … because you’ve 2.9 I’m using 3.3 things are changing.
They have their own (limited) set of “constraints” through the Inverse Kinematics panel, and that’s all – making the solvers use/understand all Blender’s constraints is difficult work.
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I am sure this was covered in the lectures. IK has its own constraints, perhaps it is worth rewatching the start of using IK looking out for the part on constraints.
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Yesssss! Thank you. 
It works, everything is working now.
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In bone properties, I locked the Lock IK in the inverse kinematics drop down.
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Should I use both bone constraint and Ik constraint? Or Ik constraint is good enough for controlling the lamp.
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