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Old 3rd December 2001 | 05:59
  #10 (permalink)  
Dave Jackson
 
Joined: Nov 2000
Posts: 452
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From: Vancouver, BC, Canada
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Lu

I am trying to keep this thread very simple.

The bicycle wheel (with its rigid rim) has been used to represent gyroscopic precession in a helicopter's rotor.

The bicycle wheel is therefor an excellent candidate to dispute this belief.
I believe that;[list=1][*]a bicycle wheel with individual weights is a better representation of a helicopter rotor.[*]a bicycle wheel with individual weights does not exhibit gyroscopic precession.[/list=a]
You have agreed with line 1.

heedm, with a lot more knowledge in dynamic then either of us, has agreed with both lines.
___________

Re line 2.

Vacuums and gimbals complicate the discussion, so lets keep it simple and only consider the bicycle wheel.

The following two question are asked in all seriousness.[list=a][*]Assume that the spokes are all attached (hinged) at the very center of the bicycle's axle. Take a wild guess at how many degrees of rotation will be required to realign the weight's plane with the axle's plane.[*]Assume that the hub now has a very large diameter, which is 90% of the 'wheels' diameter, and that spokes are all attached (hinged) to the rim of this hub. Take a wild guess at how many degrees of rotation will be required to realign the weight's plane with the axle's plane.[/list=a]

[ 03 December 2001: Message edited by: Dave Jackson ]
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