View Full Version : Speacial shoulder Rig

08-23-2013, 03:16 PM
I can get really good arm deform accept when raising the arms. I tried adding weight maps, but it doesn't work that well. In the video, the arm twists and even though it's a cartooney character, this looks like cow dun.


08-23-2013, 03:28 PM
The reason you're not getting a good deform on the shoulder is because you're not accounting for the shoulder girdle which consists of the clavicle and scapula. You need to have rotation in the whole shoulder structure, not just the arm.

08-23-2013, 03:53 PM
Yeah, what he said about the clavicle... the arm doesnt actually raise that way, it only goes up to Tpose, all other lift is of the shoulder. As for the twisting... thats because you're twisting it.

08-23-2013, 04:47 PM
Just see the first 12 seconds or so of this video on the shoulder. Watch how the clavicle and scapula rotate upwards with the arm. The rest of the video does give some insight into the workings of the shoulder joint.


08-24-2013, 08:29 AM
Awesome! I keep thinking that one rig setup fits them all, but it doesn't work that way. This setup is much better and I have a better understanding of the shoulders and how the thing moves. Thanks guys.


08-26-2013, 07:41 AM
Oh very nice toon3d.
I have been having this nightmare with my shoulder rigs as well and for the life of me I can't get the info given here to effectively work in my scene:(:(
Can you share your test scene so that I could take a look at how you laid out your bone structure?

08-26-2013, 09:04 AM

08-26-2013, 09:56 AM
See here...


You see... the shoulder deform is basically done by nothing more than using "spacer" bones to allow the deformation to spread rather than being a hard corner.

This has certain caveats... If you're animating on FK, then you have 2 bones (or more as in toon3ds example) to manage... if using IK, then youre SOL as the IK needs to start from a single point and remain planar to function correctly... hence, why I use a separate deform rig over the top of the control rig. There's a few ways to juggle the whole thing, but mostly you'll always be led down eventually to the same set of problems and solutions, or at least very similar ones.