Epicyclic motion and precession

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The discussion centers on the concepts of epicyclic motion and precession, specifically whether rotating while moving in a circular path constitutes precession. It is clarified that if a person is standing straight and rotating without moving forward or backward, there is no axial precession occurring. Precession typically involves a change in angular momentum, which does not happen in this scenario. The distinction between torque-induced precession and torque-free precession is noted, with emphasis on the fact that precession involves a wobble in the axis of rotation. Ultimately, the conclusion is that the friend's interpretation of precession is incorrect in this context.
warfreak131
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Imagine I am standing but not moving forward/backward, but I am rotating my body about my own axis. Now imagine if I moved in a circular path as I was spinning on my own axis. Is this considered to be precessing (assuming the axis of rotations are always in the z direction)?

My friend says it is, but I disagree. Wouldn't I always have the same angular momentum? And torque induced precession requires a change in L? Now I know there is a torque-free precession, but I didn't quite understand it. Can someone clear this up?
 
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See http://en.wikipedia.org/wiki/Precession

If you are standing straight there is no axial precession; precession induces a wobble in the axis of a gyroscope.

So your friend is wrong - unless he means something else by the term precession.
 
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