Senior Design Project: Interactive LED Array

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Senior Design Project Interactive LED Array

• By Khadijah Abdul Latiff
• Chong, Wee Siong

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Contents

• Introduction
• Initial Design
• Testing of Individual Components
• Explanation of Design
• Testing of Design
• Performance and Results
• Future Considerations

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Introduction

• What is the motivation?
• Where did the idea come from?
• What are the functions?
• What are the benefits?

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Initial Design
SENSORS
Analog MUX
User control
Microcontroller circuit
LED Driver
LED Array
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Testing of Individual Components

• Critical components in design
• Color sensor
• Tri-color LEDs
• LED Driver
• PIC Microcontroller

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Testing of Individual Components

• Color sensor Avago Technologies
• Responsivity of sensor
• Testing conditions
• Ambient light
• Type of object
• Distance from sensor

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Design and Fabrication

• Color sensor circuit
• White LED
• Black cover to absorb ambient light
• Follow application notes
• Noise reduction using bypass capacitor 0.1?F

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Design and Fabrication

• LED array
• Simulate ON/OFF
• Simulate PWM

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Design and Fabrication
SENSORS

• PIC microcontroller
• Run test program
• I2C protocol

Analog MUX
User control
Microcontroller circuit
I2C
LED Driver
LED Array
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Solutions

• PIC Microcontroller (Different Algorithms)
• Analog Circuit

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Analog replicating circuit
Non inverting Op Amp
Color Sensor
Non inverting Op Amp
Non inverting Op Amp
Tri Color LED
op amp to manually calibrate color accuracy
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Gain Adjustment
Trial and error method
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The color accuracy test

• The orange test
• Measure with another color sensor
• Performance within 10
• Color sensors may vary in response

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Analog replicating circuit

• PROS
• Intensity
• Unlimited spectrum
• No PIC required

• CONS
• Trial and error
• Limited resistor values
• Require amplification for every signal
• Larger circuit
• Even larger circuit is needed to integrate a
  contrast function

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Color LED Panel

• Gradient color as object move across sensors

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Solution 2 PIC Microcontroller

• Performs both replicate and complement functions.

Color sensor
Tri-color LEDs
PIC
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Replicate
RED
2 1
2 1
1 2
1 2
blue
Green
2 1
1 2
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1)
PIC
DC Power Supply
Multimeter
Tri-color LED
2)
PIC
DC Power Supply
Multimeter
3)
PIC
Color sensor
Tri-color LED
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Results

• Vred gt 0.5 Vblue Vred gt 0.5Vgreen --?
  output red
• Vbluegt 0.5 Vred Vblue gt0.5 Vgreen -?
  output blue
• Vgreen gt 0.5 Vred Vgreen gt 0.5Vblue -?
  output green
• Replicate Function was chosen
• Vout from sensor Conditions checking
  Observation
• Vred 0.23 V output red RED
• Vblue 0.105 V do not output blue
• Vgreen 0.075V do not output green

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Results

• Complement Function was chosen
• Vout from sensor Conditions checking
  Observation
• Vred 0.23 V do not output red
  BlueGreen
• Vblue 0.105 V output blue
• Vgreen 0.075V output green

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Comparisons

• Analog circuit PIC
  microcontroller
• 1) Control of intensity 1) Less components
• 2) Higher Accuracy 2) Better Performance
• under room environment
• 3) Replicate Less colors

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Using the PWM Module
Analog DeMux
sensors
LEDs
Analog Mux
LED Driver Circuit
PIC
(15 Signals)
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Future considerations

• Get I2C protocol to work between PIC and LED
  driver
• Other types of sensor may have better
  responsivity, or camera

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Functional Application

• Lighting helmet for Formula 1
• LED disco dance floor (MIT)
• Airplane lighting to help regulate sleep
• Phillips Ambilight TV
• LED Traffic lights
• Fault indicators for transmission lines

http//www.triz-journal.com/archives/2005/02/03.p
df http//web.mit.edu/storborg/ddf/
http//www.airguideonline.com/airguidemonthly/
airguide0622.htm http//www.flattv.philips.com
/shome.htm
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• Questions/Comments?