I'm creating an animation of free precession of a cuboid in GeoGebra. The axis of rotation is not one of the principal axes (but does go through center of mass).(adsbygoogle = window.adsbygoogle || []).push({});

Since it's much easier to find the angular velocity and L in the body frame, I defined the e1, e2 and e3 axes (as opposed to the xyz coordinate system that already exists in GeoGebra as the space frame) and defined the omega and L vectors via the body frame axes. So I get the motion shown in (a). e3 is fixed, omega and L precess about it, which is correct in the body frame.

I don't know how to get from (a) to (b) now. I know I have to rotate the cuboid (the body frame axes, omega and L will also rotate accordingly since they're defined via the cuboid). QUESTION: which vector do I rotate them about and with what angular velocity?

I might also be going about this a completely wrong way, I'll appreciate any comment.

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# I Free Precession animation - body frame to space frame

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