Processing Local Project data

If data was collected with a TerraFlex Premium license and a supported Trimble GNSS receiver, data will be queued for automatic Trimble Offline GNSS Corrections to improve accuracy. Terra Office uses a processing queue to manage this data from TerraFlex Local Projects. Once in the queue, Terra Office will check each set of forms (session) within the file and determine the best available base station to use, and schedule processing for when that base station data is expected to be available. When processing of a session is complete, a manual step (see below) is required to propagate the updated form geometries and metadata to the GIS features that were created at check-in (which used the form geometries and metadata as captured in the field).

The queue is managed from within the add-in and as files are checked-in, they will progress through a few statuses:

  • Waiting for base files (queued; waiting for base files to be available)

  • Correction successful (processing was successful)

  • Correction failed (processing was not successful; you can re-check-in the file at a later date if failure was due to unexpected delay in base file availability)

It is important to note that a single file might have multiple sets of processable forms within it — a single file might require multiple processing iterations depending on how far apart (in time) the data was collected.

Base station selection and processing is done via a local implementation of Offline GNSS Corrections — the same zero-configuration workflow that exists in the cloud for other TerraFlex workflows. The base station selection itself is in fact identical (it does make a call to the same Trimble cloud API to get a list of base stations), it just does the processing locally instead of in the cloud. Because of differences in the implementation and processing engines, minor discrepancies will exist between local and cloud results although a comparable level of accuracy is expected. It’s important to remember that the (post-)processed data, on a position-by-position basis, will only be used if it is of better accuracy than the real-time corrected data.

When using these workflows, a separate app icon (Trimble logo in a circle) shows in the bottom of your screen — this is the processing application instance managing the queue, checking for base station data, and doing the processing. Although the starting and stopping of this (console) application is generally managed automatically from Terra Office, it might be necessary in certain instances to close it manually. When exiting ArcGIS Pro, the app will be closed if no processing is pending although it might take up to 20 seconds.

Functionality for reviewing processing status and taking action on processed data is available from the GNSS Data Sessions tab in the Terra Office Field Data dockable window (for the current project) or through the Show GNSS data sessions for all projects link available in the Tools menu (for all projects; cannot propagate processing results from there).

To review processing status and take action on processed forms:

  1. Click the GNSS Data Sessions tab in the Terra Office Field Data dockable window.

  2. Review the list of sessions that have been queued or processed for the current project. The list of projects shows the user/device, session start time and end time, when processing is expected (for those queued), the number of forms, the source of the session (e.g., the TerraFlex Forms file name), the status, and whether or not the GIS features have been updated following processing.

  3. Click the column headers as necessary to sort the list of sessions.

  4. To refresh the list (i.e., to see the latest processing status), click Refresh in the upper right corner of the GNSS Data Sessions tab.

  5. To zoom to the forms within the selected session, click Zoom to.

  6. To view processing details about a GNSS data session in the queue, either double-click the row or select the row and click Details. In the details window, for files that have one or more sessions processed, additional Details… links will be available; these can be used to view the detailed processing results (e.g., base station used and number of positions in each accuracy range).

  7. To remove the selected session from the queue (e.g., after it is corrected and the GIS features have been updated), click Remove. This does not affect the features that were created or updated from the session.

  8. To review the accuracy and other details of the form(s) in the selected session, click Show forms. For more information on reviewing form/feature details (Form QA), see Reviewing data quality.

  9. Once a session has been automatically processed (see the Status column), you must manually propagate the updated form(s) geometry and metadata to the linked GIS features. Select the processed session and click the Update Features button. You must also select a state of the forms in the dropdown next to the button:

    • Use Processed: uses the form geometries and metadata after processing.

    • Use Original: uses the original form geometries and metadata as they were collected in the field (i.e., the state when they were first checked-in).