Transcript Project Meeting Two Presentation

Group Project: Water
Turbidity Meter
Group B
Outline
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Project Statement: “Design and construct a turbidity
measuring and displaying device based on the
HC08QY4 microcontroller”
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Integral components are the microcontroller mentioned
above, an LDR, an LED, and the 7 segment display
What is turbidity?
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Turbidity is a “measure of the collective optical properties
of a water sample that cause light to be scattered and
absorbed rather than transmitted in straight lines (USGS
04/96).”
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The quantity of suspended solids in a water sample
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Indicates how potentially polluted a water sample is
Our design:
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LED functions as constant light source
LDR at set distance from LED measures light intensity
Resistance of LDR varies according to intensity of light,
providing an indication of water clarity
Microcontroller records voltage drop over LDR every 15
seconds
Above measurement converted to a percentage of
turbidity, displayed on 7 segment display
0% indicates perfect transparency (clean water); 100% is
total light dispersion (very dirty water)
Basic Circuit
Basic process
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System is calibrated prior to first use
Turn LED on
Measure voltage over LDR
Convert voltage to percentage based on calibration
Output percentage to display, hold until next reading
Wait 15 seconds
Start process again
To the future
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Find more information on turbidity meter design in
general
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Adjust focus to now incorporate the specific software
coding required for turbidity meter to function correctly
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Develop code and produce functioning prototype circuit
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Test and adjust, trial and error
Questions?