Carolina North GPS Mapping of Bike Trails Team B2 (Becky and Jun)
The Project Process Pre-Survey Site Visit Creation of Data Dictionary Data Collection Data Processing and Differential Correction Map Creation Using ArcGIS Suggestions for Future Data Collection
Data Collection “Neverland” section 6 (shown in red) April 4: line feature data only (about ¾ of trail from E to W) April 9: rest of trail, plus point features
Data Collection Results April 4 trail – 568 positions – PDOP of 2.9 to 5.8 – Time coverage 4:05:55pm to 4:22:25pm – 4 to 6 satellites April 9 trail – 194 positions (one way) – PDOP of 2.4 to 6.9 – Time coverage 4:15:38pm to 4:19:37pm – 4 to 6 satellites
Data Processing (raw.ssf data files) April 4: April 9:
Differential Correction Data was corrected using Hillsborough CORS station reference data --Estimated accuracies for 1 st trail (594 corrected positions) are as follows: RangePercentage cm cm cm m 0.8% 1-2m 61.1% 2-5m 37.7% >5m 0.3%
Differential Correction (cont.) April 9 th file results: RangePercentage cm cm cm m 1.5% 1-2m 87.6% 2-5m 10.7% >5m 0.2%
Map Creation Air photo from Joe (Orange County) Export of feature data from PFOffice to layers in ArcMap All layers projected to NC State Plane (1983 survey feet) coordinate system
Suggestions for future data collection Too many “Dangerous Locations”? Pictures would be more effective if tied to nodes (as Data Dictionary option?) Use QuickPlan with Almanac to ensure good satellite coverage Collect in winter to avoid heaviest canopy Descriptive folder names/good management (once files are downloaded)