I’m extremely frustrated at the moment, because Blender 2.5 doesn’t do what I think it’s supposed to do.
I added two bones (let’s say they represent the upper arm and the forearm) and I want to disallow rotation around the y and the z axes according to the anatomy of the elbow joint. Therefore, I applied inverse kinematics to the forearm and set the chain length to 2. Then I switched to the bone panel and clicked on “Disallow movement around the y axis” and “Disallow movement around the z axis”, but it made no difference whatsoever, the bones still rotate in all directions. This makes no sense to me at all!
Maybe someone can tell me what I did wrong. Many thanks in advance!
It works for me. Note that the bones may still rotate based on the IK solver - the “Disallow” functions limit the motion of bone along the x, y, and z axes. Try setting it up again from scratch and see if you missed a step. Good luck!
I watched a tutorial to see how it works and I did it exactly as explained in it. But for any reason, it doesn’t work for me. This is so annoying! But thanks for your answer, of course
edit: hmm, it seems to be a bug or something like that. There’s even another mistake: if I click on “limit movement around the x axis” or “…the z axis” a red and a blue cirlce appear on the screen, respectively. But if I click on “…the y axis” there’s no according green circle. I could cry
Now that you mention it, I have never seen the green circle for limiting y rotation, and I checked in 2.49 and indeed it never shows up, so I think this is intended. Just last night, I was working on rigging something mechanical and I needed to lock down 2 axis on 3 bones in an ik chain, and it works. I just tested it now on 2 bones with a targetless ik set up on the one bone, and I had no problems locking all 3-axis on the second bone. I’m using 2.56a beta from blender.org, perhaps if you are using a newer build, the function is broke as a result of a bug fix for something else. Care to upload the .blend…
Well, I start to think that I may just have misinterpreted something. Probably Blender does behave as it should for me, too. When I just grab and not rotate the forearm it has exactly the effect I supposed. So, sorry for opening this thread, this was surely a bit too rash. I’m obviously a bit confused
You shouldn’t be able to rotate an arm bone that is part of an ik chain, unless you have a targetless ik set up (no target filled in the in the constraint field). Select the bone with the ik on it in pose mode and look at the name of the constraint, if it’s background is red, then that means it’s not set up right, aka targetless ik. Yes it can seem to work alright, I’ve used this myself a few times to basically add ik functionality to fk bones. But yeah, I don’t really know how well locks would work if the constraint isn’t fully set up.
