Two part arms

[Jon Chambers]

I rigged my arms into two sections, above the elbow, and below the elbow. However, when I rewatched the tutorial I learned that the standard method is to have the arm be one image, and have that image bend from within character animator.

Is there away, either in the current version or the next big update, to have two-part arms that are dragable from the hands? (I just don't like the lack of control I have over how the elbow looks in the current method.)

[oksamurai · Accepted solution]

I think there's a way with stapling and hinging parts together - I saw someone do it with a paper doll style puppet before - but truth be told it's not going to be a full inverse kinematics system (yet) like I think you're going for. For CH's current limitations I'd say having one arm with two draggables (in the hand and elbow) is the best way to go for better control (at least for recorded pieces).

[Jon Chambers]

Yes, that's what I thought I'd have to do. It will be frustrating when I know the distance I want the character to reach, but not the required angles to get there, but I guess I'll just wait for the next update

[lessdauphins]

I am wanting two part arms as well. Has this had any updates since this was posted?

[TheOriginalGC]

Inverse kinematics has come a long way since this was posted. You can add it to arms, legs or both.

[lessdauphins]

But can you have an arm with a separate upper and lower section with a hinge in the middle? So far I have only seen rubber hose style.

[alank99101739]

I don't think IK can handle segmented arms yet (by which I mean, drag the hand and IK will work out elbow movements for you) - so you still have to drag the elbow and the hand to animate it. BUT! The recent full body tracking support *does* track the elbows and hands, so segmented arms with full body tracking might be a workable solution if really needed.

The other approach that can help is to group the upper and lower arms separately (fill and outline) with a bit of overlap, with sticks right up to the joint. Sometimes you can get it close enough to looking segmented even though it really is a rubber hose.

[TheOriginalGC]

Use the stick tool to prevent rubber hose action.

[lessdauphins]

Yeah , it's not doing what I want. I want two rigid arm segments with a pivot hinge in the middle, no pixel warping at all. 

[alank99101739]

People who do two segment arms normally have Body with a nested independent Arm group, then inside the Arm group is another nested independent LowerArm group. The nesting is needed for the lower arm to attach to the upper arm, and the upper arm to the body.

The problem is if you drag the wrist, it will not drag the elbow as the wrist is in a nested indepdnent lower arm group. If you record a dragging event for the elbow in one pass, then the wrist in a second pass, you can record the arms (but its a pain). If you use upper body tracking with the webcam, it can control both the elbow AND the wrist at the same time, which does work. But you don't get the precision of mouse movements to control hand positions etc.

[k_oshiro]

I am not good at English so I may not understand the conversation correctly.

If you are hoping to bend the elbow at a sharp angle, is this something you would like to do?
Do you mean that you want the elbows to be connected with a hinge connection instead of a welded connection?
Please see the attached sample video.

If so, the video with Japanese explanation is helpful.

https://youtu.be/yCKxTdkqxys

Thanks.

[lessdauphins]

The example at the start of you video looks good. I will have to spend some time studying it to see how you did it though !