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Umbrella Vane
A weathercock keeps the umbrella turned into the wind, so that it doesn't blow inside out. | |
The thing that inside-outs an umbrella is the wind hitting its concave side. To prevent this, you should have a weathercock on the top of the umbrella controlling a set of cables parallel to the shaft. The whole top part of the umbrella should sit on a universal joint, constrained by those cables, and
the weathercock should ensure that the convex surface of the umbrella is always turned slightly into the wind, that being also the direction from which the rain is hitting you.
The technical idea here is to use the power of the wind, as captured by the weathercock's tail, to move the canopy of the umbrella approximately at right-angles to the wind. In a way, it would be comparable to what a sailing ship does when 'reaching' across the wind. Not closely comparable, however.
It's working.
http://www.westcoas...lla-weathervane.htm [2 fries shy of a happy meal, Feb 02 2007]
unbrella
Unbrella - unbreakable brella elf promoting [pashute, Aug 28 2016]
[link]
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Great idea! Of course, making it foldable
like a classical umbrella would get slightly
technical. |
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You say that as if it were a bad thing, [bigsleep] ;) |
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Anyway, the kind of weather which will bring this invention into its own tends to clear the streets of the trepid. |
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Well spotted, [2 fries], but the thing in that picture is rather the opposite of what I had in mind; that umbrella is always pointing downwind, whereas the object of the game here is to make it always point upwind. |
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Some more thoughts, [bigsleep]:
1. The weathervane itself would rarely extend laterally further than the rest of the umbrella, so you could only injure yourself on it by leaping through the air, in which case it would hardly be more dangerous than the end of a normal shaft.
2. This type of umbrella, being less tugged by the wind, would make fewer sudden movements* relative to the ground, and would therefore *reduce* the risk of spoke-poking to passers-by. |
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*I mean displacements, as opposed to changes of orientation. There'd be more changes of orientation. It probably wouldn't be a good umbrella to share. Hmm... I mean, it probably wouldn't be a good umbrella to share with someone you liked. Passers-by, on the other hand - perfectly safe, honestly! ;) |
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The problem with umbrellas is that they're all
wrong. |
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Conventional umbrellas are made of stupidly
imperveable material which not only stops
raindrops, but also catches the wind. |
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The point of an umbrella is to stop raindrops
reaching the person underneath it. This can be
accomplished with a simple mesh, with about 1-
2mm between threads. |
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The future belongs to knitted umbrellas. You
heard it here first. |
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