Mesh doesn't move with armature?

Question

I have a problem with an armature. When I put only one bone in one mesh it works, but I want to put a few bones in one mesh. Is that even possible? It works in this video (https://www.youtube.com/watch?v=n0VspDUOErE) but it doesn't work for me. Sorry for my English.

Answer 1

you have to parent the armature to the mesh, in order for the mesh to follow the bones.

1. set the 3D view in wireframe mode (Z key): it makes easier to see more than one object in the viewport
2. create the mesh (start with something simple, but the more vertices and subdivisions it has, the better will deform), leave it object mode
3. create the armature with all bones needed, leave it object mode
4. select the mesh and then shift-select the armature: you should then have the mesh selected with a dark orange outline and the armature with a lighter orange outline
5. press ctrl+P key and the armature parent menu shows up
6. for now, select armature deform -> with automatic weights
7. now select only the armature, and go to pose mode
8. select the last bone (the last in the chain) and try rotating it, the mesh should follow. If you rotate the first bone in the chain all other bones will follow, and so all the mesh will follow, too.
9. if ALL the mesh follows the single last bone, maybe the mesh wasn't subdivided enough when you parented it. no problem:
10. to restart the parenting, select only the mesh (object mode) and press alt+P key, and choose "clear parent". then, subdivide more the mesh to make it more easy to deform following the single bones. When done, go back to point 4)

Using a multi-bone armature, each bone can be parented to specific mesh vertices, so that each bone influences the movement of the related vertices. The video you linked shows this at this point: https://youtu.be/n0VspDUOErE?t=421

The relation between a bone and mesh vertices is not exclusive of that bone, though. Other bones could influence at least part of the same vertices, if you decide so. Each bone can be set to influence a set of vertices with a variable degree of "weight". When more than one bone moves, all the influenced vertices are moved following the overall weights attributed to all parented bones of the armature.

This is a process usually known as "skinning", you can learn how here: http://www.blender.org/manual/rigging/skinning/obdata.html

Answer 2

When building your armature, make sure each bone (after the root bone) has the previous bone as its parent. In edit mode, click the little ball at the end of the bone and hit 'e' to extrude it. After building your armature make sure all the bones act like you want before the next step.

Then select your mesh in Blender. Then hit Shift key and select your armature. so now both are selected. then, 'Ctrl P' and select Automatic Weights. AFter that, select the Armature and put into 'Pose Mode'. Now try rotating the bones and see if that works for you.