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Old 12-13-2006, 06:05 PM   #66
Erick Mead
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Dojo: Big Green Drum (W. Florida Aikikai)
Location: West Florida
Join Date: Jun 2005
Posts: 2,617
Re: For Ted Ehara - Boundary of your aikido?

David Knowlton wrote:
My friend asked how I loaded uchi mata so easily .... The leg bearing the weight is not being used muscularly - the bones and fascia form nice little triangles with minimal effort on my part. .... strength in static - linear compression, triangles etc.
As a model, the adaptive truss you describe is not terribly apt anatomically. An adaptive-jointed chain is a better one. See this structural image: for something that does make sense -- anatomically and mechanically.

To illustrate the significance of this model, let me follow up on your earlier bicycle stability question:

Fold a chain in two and hang both ends from one support. Then let one end drop from the support.

How would it fall in relation to a simultaneously dropped ball?
Less acceleration? Same acceleration? More acceleration?

With the ball terminal velocity is reached when drag equals gravity.

Does the falling chain tip have the the same limitation? What limitation does it have? Greater or lesser, and by what magnitude ?

What the falling chain achieves in pure tension -- the linked chain of body and limbs can adaptively achieve by proper kokyu in pure compression.

As per the illustration cited above. You cannot do that with a truss.


Erick Mead
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