Armature Modifier and Vertex Groups Issue

Greetings,

I am currently taking a course on blender. I am in a section dealing with animating a scene using models we built from scratch. Right now we are dealing with grouping vertices and then applying them to an armature using the armature modifier. In theory, if my vertex groups are named the same as its corresponding bone in the armature, everything should connect together, easy-peezy.

Of course, had it worked out I would not be posing here. Again, if I figured out how to deal with it, either through the course’s forums or other available resources online, I would not be posting here. I have been working on this for a few days, so I decided to extend my inquiry to other forums to see if I can obtain an solution.

Issue 1:
When I add the armature modifier the model breaks apart:

Issue 2:
Once I figured some way to keep the model together, scrunch issues began to occur. See below:

My Procedure:

  1. Orginal: Each part of the model were separate pieces.
  2. Un-parent: I un-parented each piece from their respective bones.
  3. Apply: I applied all modifiers and scale/rotation.
  4. Vertex Groups: I made sure that each piece were in their own vertex group, and that these were named according to the bone they would hook up to.
  5. Join: I joined the separate pieces together into one object. I double checked to see if my vertex groups were properly named and properly assigned.
  6. Armature Modifier: I added the armature modifier, but as soon as I pointed it toward the armature, the whole thing broke apart.

Observations:

  1. Origin: It seems to be an origin problem. Applying scales and rotations do not improve the situation. Nor are the vertex groups assigned wrongly or misnamed.
  2. Rest/Pose: I was able to “fix” the explosion problem by giving the rest pose the active pose. All parts began to fit together without exploding.
  3. Active pose: However, now the active pose “scrunches” up the moment I touch anything on my animation key frame. But If I return the rest pose to its original one, everything explodes again.

I would post more images, but since I am a new user that will not be feasible.

Although useful for exporting, it is not crucial that I figure this out right away. Since the section is about animating, this lecture dealing with armature modifiers and vertex groups is too me simply an inconvenient aside.

without knowing the scene and partly you have described it,
I would check again the following:
Is there a difference when you switch between Posemode and Editmode with selected Rig!
The geometry parts are all scaled to 1 and translation and rotation are all set to zero,
the geometry has no animation keys, no double modifiers.
On the picture it looks like the geometry does not have the orign in the center, this can not always be avoided in this case it could be .
Do you use an Ik-chain if yes it is straight in the rest-pose?

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Thank you for the check list, I will go through it and see what I can figure out and then I will post the results.

Yes, there is a difference. From the object mode to the edit mode they are different. The edit mode is the same pose as the rest position in the pose mode. The pose in the pose mode is the same as that in the object mode.

What do you mean by translation? I am used to scale, location, and rotation, but I do not recall what translation is.

This is probably the case, I will have to check it. Is there a way to fix this or work with this?

What sort of pictures or information would help clarify the issue more?

Would it be of use to isolate my model from the animation?

location(translation other App) is fine.

maybe you can share the scene or at least the lamp with rig
here as blend.file.
Otherwise before you assign the armuture press this button in posemode,

press

the bones should be identical to the editpose.

Now Parent the geo to the Armature.

if you now go back in PoseMode press the Pose Position,
now the chains should jump to the position you mentioned, select all, press Alt r and then Alt s should also show the pose like in edit mode

The position snapped back to normal, although once the animation begins, it break apart again.

I have uploaded the file that contains the scene… well, scenes. I have added the other two so that it can be seen what I had working as compared to the results when I began switching the rig over to vertex groups attached to armature modifiers.

Here is a Zipped version :

5.150_Animating_Lamp2.7z (3.8 MB)

If it would be helpful, I can always attach what I had working as a comparison.

no, I can’t solve that,
I suspect that the error has sneaked in before.

In general, I would recreate the rig in a fresh scene,
the lamp should be centered in the worldcenter starting from the foot!
One bone has an Ik-modifier?! do you want to use ik or fk to animate?

I have rigged a lamp as I would do it, only the most necessary,
the display I have set to B-Bones.
at the foot I have a front and backbone (these have no deform properties) for rolling off when hitting the ground,
the main is for postion only!

The lamp-geo you used I could not align that it stands symmetrically, I took the other to rig.

append the collection NEW in your scene

new.blend (3.7 MB)

Thanks for the rig up @walt1 , it will serve as a nice “clean” rig as an example for future projects.

A left over from one of the lectures I think. We played with one, and then the other…

Having looked at your rig I think I can see what happened, but as you said, probably not easy to fix at this point.

The issue: Courses are not always “clean” and work in a proper flow. It is a sandbox to get dirty in and things simply happen, useful or not, in that process as you learn. This course is my first time with blender (I started the course in February), and this section is my first exposure to animation and its workflow.

So we first rigged a model as different objects and then animated it. In that process I lost center of origin. Then I was taught to rig it another way.

The instructor did mention that you would normally do this second sort of rigging as you model, which in the course was one of the last lectures in that section.

So now this model, which I had since made many different changes, and now am joining into one object, must use vertex groups and armature modifiers… If I followed everything up to that point and did not forget anything.

Solution: If I keep this in mind when I rig something in the future I may avoid having a similar issue. The animation I created is not ruined if I keep it as I had it. So I am going to finish it as it is and take it as a learning experience.

If you want I can send the animation to you once I render it out. It won’t have any sound at this time, but that is not the goal at this point.

yes the learning never stops,
and you learn from your mistakes,
maybe you can see something interesting here

otherwise good luck and always have fun