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20 June 2019 00:38

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### Question

Subject: vectors
Question: Hello,
What happens when a universal joint is used as a shared pivot to two counterclokwise spinning gyros held aloft, side by side in a rearward toutching alinement and let to fall into gravity?
Date: 30 May 2014
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Hi Glenn. If I understand your question correctly, this is essentially a double armed gyro where both arms are side by side. The device should act just like a regular single armed gyro but may have a smaller drop distance and may precess at a different speed. I would have to think about it more to be sure.

Interesting idea.

regards,
Blaze

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Answer: Glenn Hawkins - 01/06/2014 06:56:10
Hi Blaze,
Thank you. I have done a poor job explaining these questions. Each gyro would precess forward; one side curving right and the other curve left, until they collided in the forward position. In the beginning from rearward touching, the opposite arcs of the pivot would receive dual reaction forces that CURVED into one another, thereby counseling part of the force. In the front just before they meet, they again counsel some force against one another at the pivot by partially pulling outward. This is a question about opposite curved vectors into one and out from another

If I have not done a good enough job explaining, I will keep trying.

Thanks,
Glenn

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Ok, I got it now Glenn. Assuming the two gyros were exactly the same and there were NO pivot friction to prevent it from moving, the pivot would move directly "backwards", it would not curve. The pivot would accelerate backwards from zero starting speed to the maximum backwards speed when the gyro arms had moved 90 degrees from their original starting position, then continue backwards but decelerating to zero speed again when the gyros crashed into each other 90 degrees later (180 degrees from their starting point). The center of mass would not change in this scenario.

regards,
Blaze

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Glenn, the movement should look very much like the video I posted with the blue platform.

http://vimeo.com/96423217

cheers,
Blaze

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Answer: Glenn Hawkins - 02/06/2014 15:28:00
Very good, Blaze. The curving vector against one another on the universal-joint, force the flywheels gradually outward as if the wheels were experiencing additional centrifuge. The pivot then acts like your testing cradle. Good analogy. It seems no mater what you do nature compensates to keep linear and rotation action separate and conserved from one another. Who wrote this law; God? I think.

Thanks, Glenn

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Answer: Ted Pittman - 09/06/2014 12:03:02
This topic has been thoroughly analyzed in the following paper:

C.G. Provatidis, Forced precession in a spinning wheel supported on a rotating pivot, Mechanics Research Communications 52 (2013) 46– 51. http://www.sciencedirect.com/science/article/pii/S0093641313000864

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Answer: Glenn Hawkins - 09/06/2014 17:54:14
Thank you Ted,

C. G. Provatidis’ mechanics are different from my own and vastly inferior. Whether that is true, his treatment does no apply to my question so far as I can see. Granted, I am not paying to join a site questionable to me, so I have not investigated his treatment thoroughly, but I see enough to suggest the following.

Perhaps I am unable to convey what is in my head. So far, I find only Blaze understands and certainly not always.

I fault myself. Today I am thinking I must be inadequate in expressing myself, though that is my profession. I am sort of giving up buddy.

You take care now and thank you again for your non-stupid reply,

Glenn,

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Answer: Ted Pittman - 09/06/2014 20:03:54
Hello Glen,

No doubt, we are all doing the best we can.
http://www.gyroscopes.org/forum/questions.asp?id=1702

Regards,
Ted

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