Rigging elbowpad in Blender

Ruflse

Hello PC, I have a problem trying to rig this metallic elbowpad with its straps.

The idea is making the straps deform with the arm, for which I'm using Mesh Deform; but I want the elbowpad to simply follow the movement of the arm without any deformations. Since it's a single object I can't use vertex parenting because it would move the whole piece, and even if Mesh Deform lets you use a vertex group to only deform part of it I don't know how to make the pad simply follow the arm without splitting it. What would you recomend?

Alex_J

Not sure I am understanding your description precisely, but I've rigged similar things in Maya before. 

Like you described, I had a blend of weight paints along the straps so that they stretch, and then with the rigid piece, I select the entire mesh and give 100% weight to the relevant joint so that we simply follow it. In fact, you might leave the elbow pad mesh out of the initial bind, and simply parent it to the relevant joint, or bind it solo by selecting it, then the joint, and binding. 

Is the problem that the rigid part of the elbow pad is connected to the straps? If so, just detach them so that the rigid part is a single contiguous mesh. 

Was that what you meant?

.Wiki

Add a joint / bone / deformer (depends on how you call it) where the pad is meant to be. Then constrain it with 50% weight to the forearm and upperarm. Voila it won´t deform but move with the arm. The straps can stay like they are now since you want them to deform with the arms.

Mark Dygert

Yep, if you want it to not stretch and to act like an actual elbow pad, then elbow joints that float between the bicep and forearm are a great way to handle it, if you're rig/game can handle the extra joints (you'll want to do it to the knees also, maybe shoulders too) and most rigs/games can support that without a problem.

It can even help the deformation of your base models that don't have padding or armor.

Ruflse

Thanks for your help guys, I've tried doing what you said: I created a new bone for the pad that moves with the rig and gave the vertices of the pad 100% weight for it and then distributed the weight of the straps between the two arm bones. I had some problems because the pad was getting separed from the elbow during some deformations but then while I was writting this coment I realised I had to give the elbow some weights to that bone too so it moves closely to the pad.



Man, I tried some crazy things with parenting and constraints and didn't think of this before.
I have to change the weights for the strips a bit but I mostly got it solved with the pad now. Thanks a lot!