2.1 Import GPS Data

One of the easiest and most common ways to create new geospatial data is using a mobile GPS receiver unit. GPS stands for Global Positioning System, and is a global navigation satellite system operated by the United States government that provides real-time position and time information anywhere on Earth. A GPS receiver captures orbital position and time information transmitted by four or more orbiting GPS satellites and uses this data to calculate its own geographic position in latitude, longitude, and altitude coordinates. For more information on how GPS works, visit the GPS.gov website.

GPS receivers can record their position for later reference in three ways: as waypoints, routes, and tracks (Figure 2.1). Waypoints are point locations defined by a set of latitude, longitude, and altitude coordinates, along with a name and description given by the user. Routes are pre-defined paths created from waypoints or points of interest located from map software on the GPS receiver. Tracks are sequences of points called trackpoints, which are recorded automatically by the GPS receiver at regular intervals of time or distance. For example, a GPS receiver might be programmed to record a trackpoint every 50 feet. Tracks are thus similar to breadcrumb trails, and can be transformed into vector line features by GIS software.

Import GPS waypoints into an ArcGIS Pro project

GPS data is stored in GPX format, a human-readable format that can be opened and viewed in a text editor. In order to be used in a GIS project, data collected with a GPS receiver unit must first be converted to a native GIS format, such as a shapefile or geodatabase feature class. In ArcGIS Pro, this can be done using a geoprocessing tool called GPX to Features.

If you are using waypoints and tracks that you collected with a GPS receiver unit yourself, copy the data from the receiver unit to a GIS data folder on your computer before proceeding. Refer to your GPS unit’s documentation for instructions on copying the data to your computer. If you downloaded or were given GPX files from somewhere else, place them in your GIS data folder before proceeding.

Action Sequence

1. Open ArcGIS Pro and create a new map project. See Section 1.1 if you need a refresher on how to do this.

2. In the Catalog pane, add a new folder connection to your GIS data folder. See Section 1.3 if you need to review how.

3. In the Analysis ribbon tab, click the “Tools” button to open the Geoprocessing pane.

In ArcGIS Pro, the Geoprocessing pane gives you access to many tools that manipulate and analyze geospatial data. You will make use of this pane a great deal in the coming chapters.

4. In the search bar at the top of the Geoprocessing pane, type “GPX” (Figure 2.2).

5. Click on the box of the first result, “GPX to Features”, to open the GPX to Features tool.

6. On the right side of the “Input GPX File” field, click the Browse button (which looks like a folder icon).

7. In the Input GPX File window, on the left side, under “Project”, click “Folders”.

8. Navigate to the .gpx file in your GIS data folder that contains the GPS waypoints, then select the file and click OK (Figure 2.3).

9. In the Geoprocessing pane, on the right side of the “Output Feature class” field, click the Browse button.

10. In the Output Feature class window, on the left side, under “Project”, click “Databases” (Figure 2.4).

Every ArcGIS Pro project includes a geodatabase created specifically for that project. The geodatabase is a convenient container for datasets that will be used in the project. Vector datasets within a geodatabase are called feature classes. Using a geoprocessing tool to transfer data to the project geodatabase preserves the original dataset in the GIS data folder for future use in other projects.

11. In the right side of the window, double-click the project geodatabase; or click on it once, then click “Open”.

12. In the “Name” field, give your output feature class a suitable name with no spaces (you can use an underscore character, “_”, in place of spaces), then click the “Save” button.

13. At the bottom of the Geoprocessing pane, click the “Run” button.

Perception and Interpretation: The process runs, with a progress bar appearing at the bottom of the Geoprocessing pane. Once complete, point features corresponding to the locations of the stored GPS waypoints should appear on the map, and a new point layer should appear in the Contents pane (Figure 2.5).

14. If a Catalog tab is visible at the bottom of the right pane, click it. If not, click the View ribbon tab, then click the “Catalog View” button.

15. In the Catalog pane, expand the “Databases” item, then expand the project database.

Perception and Interpretation: A new point feature class with the GPS waypoint data is contained by the project geodatabase (Figure 2.5).

Import GPS tracks into the ArcGIS Pro project

Action Sequence

16. Return to viewing the Geoprocessing pane by clicking the Geoprocessing tab at the bottom of the right pane; or in the Analysis ribbon tab, click the “Tools” button.

17. If necessary, reopen the GPX to Features tool.

18. Repeat the process you followed previously to import the GPX file with tracks as a new feature class in the project geodatabase.

Perception and Interpretation: The tracks may take longer to process than the waypoints because the file likely contains more data. When the processing is finished, a new point layer with the trackpoints from the GPX file should appear in the Contents pane, on the map, and as a feature class in the project geodatabase.

Convert imported trackpoints to lines

As you can see from the previous output, the GPX to Features tool only converts GPS tracks into trackpoints, without connecting the points as vertices in line segments. To create lines out of tracks, you need to use a separate ArcGIS tool, the Points To Line tool.

Action Sequence

19. In the Geoprocessing pane, at the top, click the back button to return to the tool search bar; or, in the Analysis ribbon tab, click the “Tools” button again.

20. In the Geoprocessing pane search bar, search for “Points To Line”, then open the Points To Line tool.

21. In the Geoprocessing pane, hover your cursor over the blue question mark icon in the upper-right corner of the tool interface, then hover over each blue “i” icon that appears to the left of each input field when you move your mouse over the field.

Perception and Interpretation: When you hover the cursor over the blue question mark icon, a large tooltip appears with a written and graphic explanation of the tool’s purpose (Figure 2.6, top). Clicking on the question mark icon will open the ArcGIS Pro Help page for the tool in your browser. When you hover the cursor over each input field’s “i” icon, a tooltip appears with information about what type of input should go in the field (Figure 2.6, bottom).

22. For “Input Features”, choose the map layer containing the imported trackpoints.

23. Under “Output Feature Class”, browse to the project geodatabase and enter a suitable name for the line feature class.

24. Under “Line Field”, choose “Name”.

25. If one of the options under “Sort Field” is a time or date-time field, choose it; otherwise leave the input blank.

26. Leave “Close Line” unchecked, and click the “Run” button.

Perception and Interpretation: The tool runs. Once complete, lines connecting the trackpoints should appear on the map, a new line layer should appear in the Contents pane, and the new line feature class should appear in the project geodatabase.