WaitLess Campus Bus Tracking Display

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WaitLess Bus Tracking Display
Matthew Brooks Chris Chidi Josh Mauldin Daniel
Nadeau Georgia Institute of Technology ECE
4007 Senior Design Preliminary Design Review
March 12th, 2009
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Project Overview

• What A display showing GPS locations of Georgia
  Tech campus buses using LEDs arranged along a map
  placed at campus bus stops.
• Why 96 of surveyed students are dissatisfied
  with current text based bus prediction systems
  which are limited to only a few bus stops.
• Who Assists campus pedestrians in deciding
  whether to wait for the bus or just walk.
• Cost Estimated prototype development cost of
  6700. Per unit cost production will be 600.

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Design Objectives

• Low Power
• Solar panel with battery
• Low power micro-processor
• Internet Access
• Wi-Fi module
• Use existing GPS data available via NextBus.com
  (XML feed)?
• Self-Sustaining/Easy to Deploy
• No wires/low maintenance
• No energy cost
• Weather proof case
• Low Cost
• Per unit cost 600

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System Functional Diagram
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Power Source

• Lead-Acid Battery, 12V, 7Ah
• Solar Battery Maintainer, 12V, 5.5W
• Provides 450mA During Daylight Hours
• Texas Instruments Switching Voltage Regulator
  (12V?5V)?

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System Functional Diagram
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Wi-Fi Module

• ConnectOne wireless module is used to connect to
  the NextBus.com server and receive GPS data.
• Uses WEP security with GTWireless.
• Information is obtained every 10 seconds by
  sending a specific URL to receive the GPS
  location of all buses on a particular route via
  XML.

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GPS Data

• Using a specific URL provided by NextBus.com,
  locations of buses on each route are saved every
  10 seconds.
• URL provides XML data feed.

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System Functional Diagram
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Micro-processor

• Arduino development board utilizes an Atmel
  ATMega168 micro-processor, 16MHz.
• 16KB Program ROM, 1KB RAM
• Large arrays are saved in ROM
• Arduino provides I2C and serial libraries for use
  with the ATMega168.

• Serial TX, RX, Ground
• Used to communicate with the Wi-Fi module

• I2C SCL, SDA, 5 V
• Used to communicate with 7 LED drivers

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System Functional Diagram
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Lighting the LEDs

• CAT Semi CAT9552
• 16 channel I2C-bus LED drivers
• 7 drivers are used to address 42 LEDs

• Common Anode RGB LED
• Any combination of Red, Green, or Blue color
• 4000 mcd brightness
• 20mA current draw

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LED Locations on Map
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Display/Board Design

• Photoshop used to create map graphic and
  calculate the LEDs XY coordinates
• KiCad used to create the schematic and the PCB
  layout
• Google Maps used to determine the LEDs GPS
  locations

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Project Schedule
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Demonstration Plan

• Daytime operation using solar charger
• Video to show night time operation
• Live demonstration of a minimum of two routes
  displayed

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Current Status

• Writing code for the Wi-Fi adapter
• Debugging code to generate LED commands
• PCB is complete
• Case is complete

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Questions?