WaitLess Bus TrackingDisplay Matthew Brooks Christopher Chidi Daniel Nadeau Josh Mauldin Georgia Institute of Technology ECE 4007 Senior Design Final Project Presentation April 24th, 2009
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.
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
PCB Board Design Verification • PCB board testing and verification • Corrected LED lead assignments • Performed diagnostics testing by lighting all LEDs using I2C commands from the Arduino processor
Troubleshooting Visual Display and Aesthetics • Tested LED visibility after assembly of display box • Decided to use heat shrink wrap to funnel LED illumination
Serial to Wi-Fi Module Configuration • Wi-Fi module network connectivity and XML data collecting • Utilized RealTerm Serial / Telnet software for module configuration and AT+i serial code debugging
Arduino Processor Programming / Debugging • Microprocessor programming and debugging • Utilized Arduino C programming platform to code and debug data communications and parsing algorithms.
Power Supply Testing • Tested solar panel power supply and battery supply • Found that the solar panel provides ~450 mA of current in daylight conditions • Original battery supply was faulty, obtained a new battery
Acceptance Testing • Compared WaitLess display with the NextBus Live Map • Performed final testing with system as standalone • Assembled final product with battery and solar panel attached and positioned system at an actual bus stop
Results • Product is capable of tracking all buses on all four routes of the Georgia Tech transportation service • Current draw of the device at peak operating conditions is ~200 mA which is well below the 450 mA provided by solar panel • Connecting to GTwireless requires external device authentication through PC • New WPA security features of GT LAWN network will ease module connectivity • Wi-Fi module sometimes becomes unresponsive after 5-10 minutes of operation • Needs a firmware update
Project Demonstration Requirements • Display the tracking of all buses on at least two routes of the campus bus service • Demonstrate the sustainability of the product i.e. solar powered • Demonstrate low current draw / power • Demonstrate standalone operation running solely on battery and solar power • Exhibit wireless connectivity and weather resistance
Future Enhancements and Modifications • Reduce the depth of the display box • Implement a smaller, more efficient battery • Solder all electronic components to one PCB design • Investigate surface mount LED technology • Place the vinyl map decal inside of transparent casing to protect it • Implement WPA security login for easier module connectivity • Expand the design to be used for other transportation services • Add an LED array panel below the map display to output text-based arrival time estimations for each stop