Gimbal lock?

[gothats]

Ok, I'm having a problem with this animation. It's for a class, and the character and rig is provided. It seems like they have NURBS circles and things as handles for animating the legs, hips, and shoulders, and we are putting the keys on these NURBS objects. The problem comes when I try to put keys on the rotate channels. If I grab, say, the Y rotate handle and rotate it, then I look in the channel box and see all 3 rotate channel values changing. Then when I play back the animation, it will end up in the pose that I set, but it twists and contorts all over the place to get there. After a little research, I switched the rotate options to "Gimbal". But then I get instances where the Z axis and the X axis are aligned, and I can't make it rotate how I want. How can I avoid this? I could probably get a scene file online if that would make it easier to understand what I'm talking aboiut.

[drblacksnake]

the easiest way to treat gimbal lock is to open graphEditor and look on rotation curves at frames where locking happens. Usually one curve sudently jumps over 360 degrees, so select keys after this frame and "add/subtract" 360 to/from their values. and so on for each gimbal-locked manipulator.

[user_deleted]

If you are allowed to change the rig, try grouping the object to itself and isolating some of the rotations. one of the axes to the group, X say, and the other rotations, Y and Z, to the object (or individual groups). it sometimes works, other times the entire rig spasms out.

[failure]

Change rotation interpolation to "synchronized quaternion". It's in preferences for default behavior or in graph editor ( curves/change rotation interp ) for selected curves.
Quaternion store the rotation info as angle around arbitrary axis instead of three angles. So there is no ambiguity.