Page MenuHome

Adding pole target to IK chain makes IK ignore limits set further up the chain
Closed, InvalidPublic

Description

Scroll timeline in attached .blend file to see what's up.

armatureA and armatureB are otherwise the same, only B has a pole target set for the IK constraint on bone2. Rotation limits set on bone2 are handled correctly on both armatures (neither is ever completely straight, because X rotation is limited), but on armatureB, limits set on bone1 are ignored.

Details

Type
Bug

Event Timeline

It's a known limitation of this option, see here:
http://www.blender.org/development/release-logs/blender-246/inverse-kinematics/

I was wondering if this bug could be reopened, or added to the new todo list on the wiki, or a explaination to why it cant be fixed.
I recently found this bug or limitation a problem while rigging.

Some reasons to IK lock the final chain bone:

  • Prevent a finger from spinning on the Y axis.
  • Prevent shoulder joint from spinning on the Y axis.

Old wiki reference seems to be gone: http://wiki.blender.org/index.php/Dev:Ref/Outdated/Release_Notes/2.46
New file with same problem:

Problem is documented in the Text Editor.

With an IK bone constraint, the last bone in the chain cannot be XYZ locked if using a pole target.

Why is this issue ignored? Please revisit this issue.

Brecht Van Lommel (brecht) closed this task as Invalid.EditedOct 23 2017, 9:22 PM
Brecht Van Lommel (brecht) claimed this task.

Please do not reopen old bug reports.

There is no particular reason this feature can't be implemented, it just takes quite a bit of work. For requesting features like this, see here:
https://wiki.blender.org/index.php/Dev:Doc/Contact#Requesting_Features