Adding armature to objects -- Many problems...

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I have a model I created and animated (see https://blenderartists.org/forum/viewtopic.php?t=12289 for it). It is made up of several ‘independent’ objects. The animation I did was by manual IPO editing – not the most modern of methods.

I decided to try my hand at updating it and built an armature to add to it (after reading some of the fine tutorials out there on the subject). So far, so good.

The problem comes when I parent the objects (like the arms) to the bones of the armature. Some objects twist and move when I do this. :frowning:

Additionally, if I manually move the objects (in edit mode) back to where they’re supposed to be, then add constraints to some of the bones, the objects move and twist out of place again!!! And this time, no amount of editing fixes them because they’re only wrong in pose mode. :x

This is incredibly maddening! :< I cannot for the life of me figure out what I am doing wrong. I’ve searched on the forum here for some clue and all I ever see is arcane references to “ALT-N” and “ALT-R”. Sometimes these appear to fix the problem and sometimes they just make things worse.

Best I can tell, there are actually three modes being affected, and all three can have completely different object (and bone!) positions when you go through the assignment process: Edit mode without armature selected, edit mode with armature selected, and pose mode.

I apologize if this is unclear. I’m trying my hardest to explain while still being very, very frustrated by the whole business. It seems utterly ludicruous to me that I can set the locations of my meshes and my armatures, but when I go to parent them together, one or both of the damn things move! Of what possible utility is such a thing? Why on Earth would they not just stay where I put them in the first bloody place???

I very much appreciate (in advance) any pointers on how to fix this (or, better yet, keep it from happening).

Thank you,
-Iain :<

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Yes, this can be frustrating. Instead of trying to get Blender to automatically twist your armatures the right way around, try doing it by hand.

Choose an orientation (for example, all z coordinates pointing up and forward) and then go to each armature and twist it in the right direction with ctrl-n and inputing a rotation like 90 or 180 or whatever is required. Do this before parenting your mesh to it.

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Okay: I have a followup that may help anyone else who searches for this problem somewhere down the line. I managed to more-or-less fix my problems! I still don’t know what causes some of them, but I did manage to work around them.

First, I deleted my armature and started over.

Next, I made sure every object that was going to be parented to a bone got Unparented with the save transformation option. Turns out a few of my moving objects were because they were being held in place by other objects they were parented to. Since nothing can have two parents, the “parent to bone” was just quietly removing the old parent (and parent transform) data.

Then, I went into Armature Edit mode, selected all bones and performed “Alt-N”. Then I manually rotated (using the N key menu) every bone I didn’t like the axis orientation of.

One by one, I parented the objects to the bones. This time, I had no problems with this step.

So, I moved on to adding constraints. And the problems came back… So I backstepped and removed all the parenting from every object that was going to have a constrained bone, then added the constraints to these bones.

This more-or-less worked. Several bones, after receiving constraints, rolled 90 degrees and moved slightly (Does anyone know why?) – but only in pose mode. I decided I could live with these changes and moved the bones in the edit mode to reflect exactly what they looked like in the rest pose in pose mode. Then I went ahead and parented the objects to the bones.

Viola! – Success! Finally, an armature that I made entirely myself (with lots of tutorial help) that works correctly on a critter!

So, my big advice to anyone else stuck on this: Do everything in the order I’ve outlined above.

I just hope like heck I don’t ever need to change anything on it… :o

-Iain

[And thanks for the reply, bob-dog! I missed it until I’d already posted this note.]