Andrew, since you are writing code you might like to incorporate compensation
tables
for the shape of the tank so you get a linear scale.
The system I have is a variant of Tony K's that weights the fuel with a 0 ~ 1"
pressure transducer. The fuel sloshing and tank shape compensation is done with
a PIC Micro. It has worked flawlessly for 10 years.
Cheers, Paul
-----Original Message-----
From: owner-europa-list-server@matronics.com
[mailto:owner-europa-list-server@matronics.com] On Behalf Of Andrew Sarangan
Sent: Tuesday, June 17, 2014 9:03 AM
Subject: Re: Europa-List: Noncontact fuel level indicator
I will take some photos and write up some details in a few days.
The idea was based on what I accidentally observed one day when holding a flash
light to the fuel tank. When the flash light is held below the fuel level, the
entire fluid lights up. When the flash light is above the level, the tank lights
up. The contrast across the fluid level is about 10x. This is due to light
being trapped above or below the level. See attached pictures.
So, I made a board with four LEDs in a column, and another board with
10 photodetectors in a column. Using a microcontroller, I am flashing each LED
in sequence, and then computing the liquid level based on the measured contrast.
The output is displayed on a 10-bar display. The LED board will attach to the
aft of the baggage bay bulkhead, with four holes to allow the light to get
through. The detector board has to attach somewhere on the front side of the
tank.
This might be the tricky part because I need to make sure it is secure, but
also removable and does not interfere with the controls.
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