Riley Smith

Tip of the Week #19 - Investigating Data with Point Derivation Reports

Blog Post created by Riley Smith on Aug 12, 2017

Using TBC to troubleshoot your field surveys is like detective work. Wondering how a specific point location got computed? Looking at the point properties doesn’t tell you much about the point info? In that case the tip below will be very useful. Point Derivation Report will be your best friend.

In this example, there is traverse, static GNSS, and differential leveling observations for establishing a survey control network.  Point 1011’s coordinates are calculated by all three observation types followed by a network adjusted value.

To create the Point Derivation Report select and right-click to view the shortcut menu and press Point Derivation Report.  You can generate multiple reports by selecting several points before running the report command.

The Point Derivation Report created from TBC is in HTML format and will be opened in your selected browser.

There are several elements to this report:

  1. The first section details the survey data and comparison of the calculated position values for each observation and coordinate

  2. The second section shows the calculated GNSS vector length and precisions
  3. The next section shows the terrestrial observations (total station) and their components

  4. This section describes the leveling observations used to calculate the elevation value for the selected point

  5. Finally, this section describes any effice entered, imported, or adjusted coordinates used in the calculations

 

Here is an example where this report can be used to find errors in a survey.  The observation in red is outside of the computation tolerances set in the Project Settings.  This information can be used to fix blunders by enabling/disabling observations, changing point ID's, and other raw information.

 

 

The Point Derivation Report can help you find all those pesky survey errors and clean up survey data to make a error proof deliverable.  Until next time, happy surveying!

 

 

 

TBC Team

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