Wobbling and Rotating Motions

Motions of two disks look similar but in fact totally different.
1. Brown disk (swashplate) is rotating. A point R on its periphery rotates. Its distance to the ground is constant. Its locus is a circle in the horizontal plane.2. Blue disk is wobbling. A point W on its periphery goes up down, so its distance to the ground is varried. It is possible to consider that point W oscillates around horizontal axis with period Pw. This axis rotates around vertical axis with a period Pr. Locus of point W is of saw-tooth shape.
The video shows case when Pr = 6.Pw. The locus of point W has 5 saw-teeth.
If Pr = Pw, the wobbling motion becomes rotating one (like case of the brown disk).
If Pr = 0, locus of point W is a circular arc in vertical plane.

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