Cheap Pressure Sensors
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Posts: 46,084
Very good low pressure sensors exist but they cost at least about $40.
But, Scott Edwards, in Stamp Applications no. 27 (May '97) shows us how to
'Measure Water Level Without Getting Wet'. He uses the difference in
dielectric constant between water and air. His idea is to make a capacitor
in which water level changes the capacity which, in turn, can easily be
measured using a stamp.
Changes of liquid level in a constant diameter container mean volumes of
liquid, so that some math should do the dispensing trick.
All alcoholic components of mixed drinks (fortunately...) contain quite a
lot of water, so that Scott Edward's scheme should be applicable to the
Stamp Barman project. Its merits are: low price and full instruction
available on line.
And yes, I've tried it and it works.
Dov
Original Message
From: "Leroy Hall" <leroy@f...>
To: <basicstamps@yahoogroups.com>
Sent: Wednesday, April 17, 2002 7:31 PM
Subject: Re: [noparse][[/noparse]basicstamps] Re: Cheap Pressure Sensors?
>
>
> Would it be possible to take a mechanical pressure gauge of the pressure
> required. Put it in an enclosure that allow fastening a potentiometer
> to the shaft where you would remove the dial hand from? Might work, get
> someone that only has two thumbs to build it.
>
> Tell 'em where you got it!!!!!!!!!!
>
> [noparse]:)[/noparse])))))))))
>
> Leroy
>
>
> To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
> from the same email address that you subscribed. Text in the Subject and
Body of the message will be ignored.
>
>
> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
>
>
But, Scott Edwards, in Stamp Applications no. 27 (May '97) shows us how to
'Measure Water Level Without Getting Wet'. He uses the difference in
dielectric constant between water and air. His idea is to make a capacitor
in which water level changes the capacity which, in turn, can easily be
measured using a stamp.
Changes of liquid level in a constant diameter container mean volumes of
liquid, so that some math should do the dispensing trick.
All alcoholic components of mixed drinks (fortunately...) contain quite a
lot of water, so that Scott Edward's scheme should be applicable to the
Stamp Barman project. Its merits are: low price and full instruction
available on line.
And yes, I've tried it and it works.
Dov
Original Message
From: "Leroy Hall" <leroy@f...>
To: <basicstamps@yahoogroups.com>
Sent: Wednesday, April 17, 2002 7:31 PM
Subject: Re: [noparse][[/noparse]basicstamps] Re: Cheap Pressure Sensors?
>
>
> Would it be possible to take a mechanical pressure gauge of the pressure
> required. Put it in an enclosure that allow fastening a potentiometer
> to the shaft where you would remove the dial hand from? Might work, get
> someone that only has two thumbs to build it.
>
> Tell 'em where you got it!!!!!!!!!!
>
> [noparse]:)[/noparse])))))))))
>
> Leroy
>
>
> To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
> from the same email address that you subscribed. Text in the Subject and
Body of the message will be ignored.
>
>
> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
>
>