Motionbuilder fails to plot constrained bone

Hi, I’m having this really odd issue where a constrained bone (the root of the skeleton actually, to plot root motion) fails to get rotation properties plotted.
In the viewport I can see the bone behaving as expected (it’s constrained to a locomotion arrow) translating and rotating along (oddly, the Fcurve channels show no change in the rotation values, eventhough the Viewport transform fields do)
It’s also part of the character extension, to make sure it plots whenever the animator bakes.

But baking to skeleton, or using Animation > Plot Selected > Selected properties… simply fails to plot the rotation curves (translation on the ground plane X and Z get plotted as expected).

I’m stomped, because this very same setup works ok with other characters, only difference being that to extract the rotation in this case I’m using Aim constraint (to get around a flipping axis problem).
Has anyone encountered this?

Some quick tests:

  • Ensure you have TR set as your KeyMode in the Key Controls window before plotting.
  • Check your Rotation Filter settings in the Plot Properties window as well, I’ve seen it fail or give bogus results with Unroll.
  • Uncheck SmartPlot as well.
  • It the rotation property of your root locked? you might need to set Plot Locked Properties to ensure it gets baked.

What version of Mobu is this? Also how is it constrained? Relation, Parent/Child, etc…

Thanks for the reply,
It was happening with both Mobu16 and 2018, had tried some of the things you suggested and then some, no joy… Don’t recall ever being so stomped with Mobu.
In the end I re-did the constraint system for the root motion, trying a much simpler approach with no aim-at constraint, and that brought back the rotation property to behaving on plotting.