Mapping Bus line 85
Michael AlexanderHoklan Hau
Motivation
• Public transportation provides many societal benefits
• Madison’s public transportation system is confusing to use– Lead to underutilization
Hypothesis
• By making navigation of the city of Madison’s bus service more accessible, we can increase participation
Methods
• Equipment– 3 handheld GPS recievers (Garmin etrex)– Digital Camera– GPS Software and PC
• Fieldwork– 3 waypoints for each bus stop – 5 min at each waypoint– Photo of each bus stop
Methods Cont.
• Data Analysis– Data download– Matlab
• Average coordinates• Statistics and error calculations
• Google Maps Integration– Import waypoints– Photo-tagging– Interactive timetable
OverviewGPS Receiver
GPS Waypoints
Matlab Analysis
Google Earth KMZ file with timetable and
photographs
Google Earth Metro Timetable
Digital Photos
Project Specification
• Absolute Accuracy of 6m– Bus usually stops within ~6m of sign– Rte. Markers usually within plain sight
• Interactive Google Map– Route– Picture– Timetable link
Results
• Average Error: 5.24m• Outlier: Lake and Langdon
– Error: 330.59m– Visual Inspection revealed two waypoints at a
considerable distance from ground position
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-400 -300 -200 -100 0 100 200 300 400-400
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Waypoint: 8505Loc: Randall & Eng. DriveCoords: 43.07198 , -89.40916333NS Error: 2.95mEW Error: 0.79mAvg. Error: 1.87m
Waypoint: 8500Loc: Lake & LangodCoords: 43.0722967, -89.40352 NS Error: 327.14mEW Error: 334.77mAvg. Error:330.95
Final Bus Map
Google Maps
Conclusions
• Needed more waypoints and follow-up measurements to increase accuracy
• Allot more time to fieldwork• Silver Etrex is better and easier than yellow
Future Work
• Map all bus stops in Madison• Integrate with online timetable search
– Bus Stop IDs in metadata– Algorithm for directions / transfers
• Look at bus users before and after interactive bus map
Questions?