Rig problems - odd things be happening.

Okay, so I just finished a rig for Alduin (I downloaded the mesh here: http://tf3dm.com/3d-model/alduin-dragon-rigged--76875.html ) and it’s great! … mostly…

Everything moves as it should - I can pose the wings, neck, jaw, tail, etc. Except, there’s one problem:
When I move the whole rig controller, the forelegs start twisting (Video: http://www.youtube.com/watch?v=CgFkRU2L7J8)

How do I fix this?

I’m new at this (if you can’t tell… it’s pretty obvious) so any help is much appreciated!

Really need to see the file to see what is going on.

A few quick basic things to check: make sure the mesh object and the armature object both share the same point of origin, scale & rotation. In the 3d view, transforms panel on the right, in object mode, make sure both the mesh & armature have a scale of 1 for xyz, and rotation of 0 for xyz. Check the origin points by selecting the mesh in object mode, shift-s -> snap cursor to selected, then select the armature in object mode and make sure it’s origin is at the cursor in 3d view. As I said, these are basic things, and steps that should be taken when you first add the armature in object mode.

But I don’t think this is your problem. Generally, when the above conditions (scale, rot, & origin) aren’t matching between armature & mesh, moving the armature causes the mesh to contort and stretch/shink like a comic book hero. I just mentioned this since you are ‘new at this’ as this should be the first thing to check when having problems.

Now here is where I think your problem is: It is only part of the leg that twists, so this is where you should start looking. I assume that you have only one bone in the portion of the leg that behaves badly. So view those bones while moving the armature and see what they do, they are probably twisting around. So the first thing I would check is to see if it’s a cyclic dependency problem (caused by improperly set up constraints), in pose mode, tab into edit mode, then tab back out to pose mode, and look at the console window for error messages. If there are no messages, then look at the constraints, looks to me like you have ik constraints on the legs, are they working correctly & set up properly?

I could keep guessing, but without a file, it’s hard to say where the problem is…


Thank you! I noticed that about the bone as well, it’s just the one in both legs (the “shin” bone) but I don’t know enough about the program to really know what the problem truly is, nor how to fix it. Here’s the file, hopefully you can help me out. http://www.mediafire.com/download/n65s84rm8mcm3vl/alduinWIP.rar

Thank you so much!

Has anyone figured anything out? I’m still stuck

you have problem with your pole target in your ik on the shin.R and shin.L I got rid of the pole target and that fixed it

If I recall, I ran into this while messing around with rigging. Pole targets have to have their parent at or downstream of the bone with the IK constraint. If the pole target is anywhere upwards and within the chain, weirdness happens. Pole targets might be needed (just deleting them removes the control they provide), but where they’re currently parented is causing cyclic dependency problems.

Alright thanks guys! I’ll fiddle around with that a bit more, and see if I can correct it.