trouble with bones influence

[miketche]

First a question. Is there a specific reason why you want to use bones on this mesh? Bones are used to deform and animate a solid mesh or so. With a robot built of separate pieces I would just reposition the axis points and asign IK to the individual parts. That way no deformation.

[JoshM]

Hi,

The problem with using multi-object geometry in a rig is that you need to parent the geometry to the bone. Now this works fine. The real problem with this is using influence maps with multi-object rigs because not only is the geometry being moved by the bone due to its Parent-Child relationship but it is also being moved by its influence maps. So this will give a multiplying effect.

To see if this is your problem resave the scene under a different name and remove the influence maps from your geometry. After that begin moving the bones and see if you experience the same problem. Hope that helps.

-Josh-

[miketche]

But if you really want to use bones then I would assign the bones with a "Set Selection" to the whole part and not a "Vertex Weight Selection".

[wesware]

Ok,

Question1: Do you have any bones without vertex restriction tags? If so, they are still influencing the mesh that you are trying to deform with the foot bone. Place empty restriction tags on all bones that aren't weighted yet so they are taken out of the equation. Or you could multi select them and give them zero strength until you decide to weight them.

Question2: Are you using R8 and if so, are you using soft IK? If so then childing your mesh to the bones may not be a solution since foreign objects in a soft IK chain are a no-no. You could (before you assign soft ik tags to prevent any screw ups) child each peice to its corresponding bone, then zero out the geometry's axis to the bone. Then remove the geometry from the bone hierarchy and, with Expresso, lock each piece to it's corresponding bone using a global matrix expression on the geometry. Any piece that has more than one bone and bends organically can be wighted using claude bonet tool.

If you are using R7 then you can either child your geometry to the bones and give the bones zero strength to keep them from deforming anything and just use them to animate the geometry based on the parent-child relationship, or get a hold of the "transfer" plug in to do something similiar to the expresso deal above. Just make sure the bone axis and geometry axis are in the same place in space before you apply the plugin. or you could child the geometry to a null that is zeroed out to the bone. Use "set-null-object" plug for that one.

You have many options...
To recap on the bad deformation... check and make sure all your bones are being restricted or at least set to zero strength if they aren't restricted.

HTH

[bobtronic]

Thanks for all replies - very appreciated.

to wesware: First thanks for your long and helpful reply.
I use Maxons "new" Cinema CE. It is the same as 6 XL.
Every bone has its own restriction tag. I think I know
how bones work and its not my first rig (but my first
multi-part rig in C4D). Its as like the bones doesn't
deform linear. I have made a similar rig in Blender without
trouble. I think I will child the geometry to the bones as
you have recommended. Where can I get the "Transfer"
plugin ?

best regards, Bob

[wesware]

If you are childing the geometry then you won't need the transfer tag.

But, you can get it at http://www.plugincafe.com

[CGTalk Moderation]

This thread has been automatically closed as it remained inactive for 12 months. If you wish to continue the discussion, please create a new thread in the appropriate forum.