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Old 01-01-2011, 04:38 PM   #30
Erick Mead
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Dojo: Big Green Drum (W. Florida Aikikai)
Location: West Florida
Join Date: Jun 2005
Posts: 2,619
Re: Direction of Groundpath

Mike Sigman wrote: View Post
Spiralling of what? You're talking about shear-forces and if someone has got spiralling forces running simultaneously in different directions on their body, I would love to know how it's done.
That is exactly what I am saying because that is exactly what shear IS. Look at the shear stress diagram on the cylinder.

Torsion (thus, spirally oriented) on the cylinder creates shear stress on the square element depicted. It is being squashed in compression in one diagonal axis (relative to the axis of the twist) and stretched in tension on the complementary (90 deg.) axis. These define two spiral of equal and opposite stress that run spirally through every element of the cylinder. These three axes also give you your "six directions" -- FWIW.

Conversely, adopting this stress profile in the body creates torsion (rotation) in the whole structure. The compressive stress profile runs from hand to opposite foot and vice versa for the tension (stretching) profile.

If coordinated they create rotational dynamics in anything connected to one's structure, and the nature of the thing makes it capable of reversing action and stress instantaneously and continuously, unless you block the action from occurring.

Mike Sigman wrote: View Post
The guy pushing the elephant's butt can't push the elephant into the truck at the same time that he's pulling it out.
Hm. With just two hands you can put a 1200 pound horse on the ground using this precise principle....

I'll leave the elephants to you ...


Erick Mead
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