GPS SOFTWARE & MISSION PLANNING

Transcription

1 GPS SOFTWARE & MISSION PLANNING GPS & GIS Fall 2017

2 Mission Planning

3 Online Mission Planning Settings Tab Satellite Library Elevation Number of Satellites Visibility Skyplot Iono map

4 Online Mission Planning Settings Tab Navigate on the map and click on your location Should show an arrow labeled Your Position Click Settings and confirm your new location Set the cutoff to 15 and use today s date and time (with 6 hour option) Click Apply

5 Online Mission Planning Satellite Library Uncheck everything except for GPS Elevation, Number of Satellites, & Skyplot Use the slider at the bottom right to investigate different times Can also look at the world view, DOPs, and ionospheric map

6 Dilution of Precision PDOP, HDOP, VDOP

7 Horizontal Dilution of Precision Measure of accuracy in 2-D position, such as Latitude & Longitude

8 Horizontal Dilution of Precision Using satellites from the 4 compass directions provides a good HDOP

9 Horizontal Dilution of Precision Using satellites from one or two quadrants provides poor HDOP

10 Vertical Dilution of Precision Measure of accuracy in 1-D position, height

11 Vertical Dilution of Precision Using satellites well spread out in the sky will provide good VDOP

12 Vertical Dilution of Precision Using satellites which are located low on the horizon will results in poor VDOP

13 Position Dilution of Precision Measure of accuracy in 3-D position, also called spherical DOP It is the combination of HDOP & VDOP caused by satellite geometry PDOP values the lower the better < 1 = ideal 1-4 = Excellent 4-6 = Good 6-8 = Fair 8-10 = Poor = Marginal > 12 PDOP is too high - Do Not Use!

14 Position Dilution of Precision

15 Pathfinder Office

16 Pathfinder Office Utilities Import/export Differential correction Data transfer Data dictionary Map (pre)view data

17 Pathfinder Office You cannot just place data to and from the unit must be transferred using utility!!

18 Pathfinder Office Log Files Most operations conducted will create a log file Status window pops up at the end with success/failure and the log file creation Check this to confirm output, settings, errors, etc.

19 Importing shapefiles

20 Import shapefiles Open ArcGIS and convert files to Lat/Long ArcToolbox > Projections & Transformations > Project Transfer to GPS unit in pathfinder office Utilities > data transfer > send Add > background file

21 Import shapefiles as background Open terrasync Go to Map view Under the Layers menu > background files Check the layer to turn it on Makes sure that under the Layers menu, background, is also checked on The background file should appear on the map!

22 Data dictionary

23 Data Dictionary Attribute Table Non-spatial information about locations Many pre-made options Date Numerical Menu Sets up a template for use on the receiver When collecting a feature, just fill in the blanks Requires planning

24 Data Dictionary Editor Name the data dictionary under Version select TerraSync v5.00 and later, and save it to your project folder. Create Features Click New feature Name it and choose a geometry: point, line, area Click OK Do this for as many types of features as you need to collect for You can have multiple kinds of points, lines and areas

25 Data Dictionary Editor Adding Attributes Select a feature from the list and click New Attribute Select the attribute type from the list and click OK Fill out the information about the attribute Name, required or not, length (for text), min/max (for numbers), default values (for menus), etc. You can have multiple attributes for each feature

26 Exporting data from GPS

27 Export Open Trimble Pathfinder Office Utilities > data transfer > receive > add > data files

28 Export GPS data will transfer as.ssf file and will include a text log of details

29 Export Next step is to perform Differential Correction Utilities > Differential Correction Select the.ssf file that you want corrected Will create a.cor file, which will then be ready for export

30 Export as a shapefile Utilities > export Specify output folder Choose an export setup Set up properties for export

31 Export properties Coordinate System Make sure the coordinate system is correct for the data you are working with Should be set in both Pathfinder and TerraSync If you do export to shapefile without a projection, use Define Projection in ArcMap to set what it should be

32 Export properties Attributes Select attributes to export on top of your data dictionary Metadata PDOP Correction Status Number of Positions Time/Date

33 Export properties Position Filter Can filter based on PDOP, angle, etc. Redundant if you have already done this on the unit If you want to export uncorrected features, you must check the box in the tab