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Old 09-30-2011, 01:17 PM
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RickI RickI is offline
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Originally Posted by ricki View Post
Good points, particularly about sliding the foils out on the axel by accident. Worse what if one falls off at depth?! Something more positive with less friction would be a strong advantage. Your suggestion of a mobile ankle mount is intriguing if I follow your meaning. That would allow more deflection of the front foils with less effort, hence easier, tighter and faster turning of the Aqueon. Also, you probably noticed the boards can become uncomfortable, it would be nice to avoid that with your ankle mounts. As DARPA ran off with Cal's idea, some study of their more contemporary design would be helpful in considering changes.


PowerSwim by Jay Lowell, DSO Program Manager


From: How to become a mad scientist for DARPA. - By Daniel Engber - Slate Magazine

and still more:




From: Ares Homepage

Sweeping back the front foils would impact your displacement in strokes but it would also reduce drag. I think the ability to feather the trailing edge of the foils would provide some strong advantages as well providing less turbulence through strokes. The rear stabilizer serves to provide resistance to excessive pitch oscillations through the sinusoiding of the front foils. You simply need something of adequate reactive force to stop you from seesawing in place through the motion of the front or propulsion foils. Going with symmetrical foils made sense from a production and performance standpoint using wood construction decades back when Cal developed this. With synthetics you could variation size, aspect ratio, etc.. Perhaps you could come up with something which would provide the necessary pitch stabilization without the excessive width. Perhaps something longer again with trailing edges that could also be feathered. I don't think fins would provide sufficient surface area to do this at least not with the current front foils. In the case of a monofin, I am less certain. When I mentioned narrowing and increasing the length of the stabilizer I was thinking of something roughly in the shape of an odd monofin. It would need to likely have more blade resistance than a monofin you would like to use on its own though, I think? It seems if your stabilizer was too long it would create excessive drag from projected area. This is one good reason to try to stick with narrower, longer foils as are currently in use.

Good stuff to work on! Other ideas out there?

Rick
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Last edited by RickI; 09-30-2011 at 01:34 PM.
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