Problem rig deformation

Hello Blender users ! :cool:

I’m on a project of a short movie with a friend and I have some problems with a part of the body of our character.

Indeed, his “shoulder” deform itself when I move the armature of the upper arm ! And I don’t know how to fix that !

Here is a gif to help you to vizualize my problem ( the wear physic is not good and i’ll fix it later :wink: )

http://cdn.makeagif.com/media/1-28-2015/DZ4sXU.gif

It will be really nice if someone could help me :smiley:

Thanks

Check the weighting for ALL bones
Check for any modifiers that affect the mesh
Check for any constraints that affect the mesh
Check the weighting for ALL bones

You have not supplied any blend file so as you are the only person who has access to the model and rig, you’ll have to do this investigation yourself

If you are unable to post a file to Blenderartist…
then go here…
http://www.pasteall.org/
then post us the link back here so we can all download your file to see what is going on…

I’m going to guess that when you parented your robot to the armature, you chose ‘automatic weights’ instead of ‘empty groups’. Automatic weights is designed for organic models, not mechanical models. With robots, when one bone moves one bit of mesh, wholly and completely, and nothing else, you should use ‘empty groups’ then go through the groups (which will have the same names as the bones) and select the part that bone should move, and assign it to the group. It’s tedious, almost as much as checking all bones and fixing any overlaps, but you only have to do it once. Unfortunately, there isn’t any shortcut to mechanical rigging. You have to do it part by part.

Thanks for your answers !
I am not able to upload the file now but I will do it the fast that I can !

@Orinoco Yes it’s true that I parented the armature with the “automatic weights” the first time that I try to. But I’ve got some problems and I reparented manually using the “empty groups” option. But I am a newbie in rigging so it’s possible that I’ve made a mistake.


EDIT:

Here’s the blend file !

Someone got a solution ?

If I’m understanding your problem correctly…

your trying to correct the shoulder from digging into the body when ever the upper arm rotates upwards…

this isn’t too hard a fix…
Make you a shoulder bone…
parent it to the chest…
place a copy rotation constraint on it so that it copies the rotation of the upper_arm…
use local, local…
not world, world in the constraint…
then make you a new vertex group named shoulder (shoulder.L and shoulder.R) and assign your shoulder to those groups …
making sure to “unassign” those vertices from all other bones…
such that now the shoulder bone only influnces the shoulder mesh…
set the rotation point of the shoulder bone back up on where it will ride on top of the chest…

here is my file…

http://www.pasteall.org/blend/34239

hope that helps…

Thanks @norvman !! :smiley:
I haven’t got the reflex to use constraints (except for IK) in rigging ! But it was the good solution finally !
I change the settings a little to see and the “pose space” (in the rotation constraint) works better for my purpose :wink: .
Thanks again !

Very Cool … Take some time to play around with Bone Rigging and using different constraints with them… you will be glad you did in the end… they are very powerful once you know what the do and how to connect them all up…

Yeah it’s a powerful tool, a little complex at the first sight, but I will continue to train.
Thank you once again ! :slight_smile: