Transcript Presentation

COLOR SENSOR
John David Noe
Dept. of Technology, EKU
OUTLINE
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Create a sensor to measure colored
objects reflected wavelength.
An economical sensor.
A high resolution sensor.
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MOTIVATION
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I have a green deficiency in my vision.
Properties of light intrigues me.
I purchased a black truck until my wife
told me I had a blue truck!
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INTRODUCTION
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http://hyperphysics.phyastr.gsu.edu/hbase/hph.html#ahph1 is
a great web site for research in the field
of physics.
www.microchip.com Microchip corp.
web site has a wealth of info on
microcontrollers and applications.
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PROBLEM STATEMENT
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Precision color sensors are expensive.
Cheap sensors only detect a few colors.
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PROPOSED SOLUTION
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Fabricate a precision, affordable color sensor.
Provide specific colored LEDs to illuminate an
object.
Use microcontroller based hardware for
sensor to measure reflected light.
Provide a PC interface to control and calculate
the color of an object.
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PROPOSED SOLUTION
Custom Fabricated Led and Sensor Holder
Leds continue in
alternating colored
fashion.
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PROPOSED SOLUTION
1. +5 Volt Regulator
2. RS232C Interface
Chip
3. PIC18F4320
Microcontroller
4. DA Converters
5. Analog Multiplexers
6. 2N3904 NPN
Transistors
7. LED current limiting
resistors
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PROPOSED SOLUTION
PC interface start up
screen.
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PROPOSED SOLUTION
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RESULTS
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Sensor is very sensitive.
Repeatability is good.
Sensor prototype economical to build.
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RESULTS
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RESULTS
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RESULTS
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Hardware performed great.
Software performed great.
Color algorithm needs a lot of work!
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CONCLUSION
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PC and PIC programs need automatic
mode.
More experimentation with other types
of sensors.
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