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From: bernie@metapro.DIALix.oz.au (Bernd Felsche)
Subject: Re: ELECTRONIC WINDSENSOR
Message-ID: <Cw9oA3.84G@metapro.DIALix.oz.au>
Organization: MetaPro Systems, Perth, Western Australia
References: <AMF.94Sep15113140@kongle.idt.unit.no> <AMF.94Sep16112239@kongle.idt.unit.no> <35cnoc$pt2@handler.Eng.Sun.COM>
Date: Sat, 17 Sep 1994 09:13:15 GMT
Lines: 30

In <35cnoc$pt2@handler.Eng.Sun.COM> cmcmanis@Sun.COM (Chuck McManis) writes:

>Arne Morten Faannessen (amf@idt.unit.no) wrote:
>: Maybe my previous message was unclear. What I am looking for is a
>: manufacturer of a low cost small speedsensor for measuring relative wind
>: velocity. I intend to use this in a Hangglider. I have seen some wind
>: velocity meassuring products, and one had a small propeller, it had a size
>: of quarter, it was inductive, and was integrated to a LCD. I am just
>: interested to buy the sensor as a seperate unit while I indend to integrate
>: the sensor to a MCU. Does anyone know of a manufacturer of such product ?.

>Sounds like a propeller on a motor and an A/D converter is all you need. 

Won't that get highly linear as the propeller 'load' will increase with
speed due to the motor? A free-spinning prop. with photointerruptor or
hall-effect sensor hooked up to a pulse-rate indicator should do the
trick until you integrate it with the MCU.... that way you only have
the aerodynamics of the propeller to worry about as a source of error.
(And it's a digital data source :-))

If you have identical sensors on both wings, you can also determine
the differential wind speed, and which one is faster... I guess that
sort of thing would be useful, not that you'll ever get me up in one
of those contraptions! :-)

How accurate does one need this sort of thing to be?
-- 
Bernd Felsche, MetaPro Systems Pty Ltd
328 Albany Highway, Victoria Park, Western Australia
Phone: +61 9 362 9355  Fax: +61 9 472 3337
