Combining fcurves of the same data-channel?

I have an armature with a walk cycle. The torso is an upside-down Y shape for the spine and pelvis. I nailed the legs and the up and down motion of the spine and pelvis. However, I realize I’d like to add a ‘swaying’ motion where the downward-diagonal pelvis bones rotate around their average z axis. Easy enough to do when there’s no keyframes, just set the maximum rotations and let bezier do the work. But my up-and-down maximums don’t match where my rotational maximums are. Unfortunately, because the bones are angled, the up and down motion occurs on the same data channels I need for rotation.

Is there a way I can set up my rotation then have blender “add” it to the up and down motion, the way I can “add” different layers of an image? It seems like there must be some methods to do this, other than just re-animating perfectly from the beginning.

I’m not entirely sure that I understand the problem or the setup, but there are probably a few things you could be looking into:

  1. NLA. This lets you blend multiple actions into a single animation. Each action has its own independent keyframes; the actions are blended together with a few choices of blend mode.

  2. Sandwich in new parents. Duplicate the hip bones, make the old hips bones the children of the duplicates. Now you have a new layer of bones you can animate. Technically speaking, this is multiplying the rotation rather than adding it, but I think that’s probably what most people mean by “adding rotation.”

1 Like

I’ve been playing with the NLA editor but haven’t figured blend modes out yet. I’ll take a look.

And that other fix is much less elegant than I’d like but I can’t believe I didn’t think of it. Just might work.