Joe Blecha

Tip of the Week #15 - Using the Best-Fit Line Command to Draft Catenary Lines

Blog Post created by Joe Blecha on Jun 23, 2017

Tip #15 - Using Best-Fit Line to Draft Catenary Lines

 

Did you know you can use the Best-Fit Line to draft catenary power lines in TBC?  This accurate and time-saving tool creates a 3D linestring that can then be used to compute and document minimum clearances, in a Plan Set, or exported in a third-party data format.

 

Here’s a typical situation:

 

 

Station View in TBC - Panorama and Point Cloud data

 

Powerline and tower data has been collected by a Trimble VISION instrument.  Included in the data are points along the powerline, either through scans and/or Direct Reflex (DR) topo in the field, or Virtual DR in TBC.  

 

In this example, the powerline data is a part of some SX10 station setup scans.  After refinement with the Classify Regions and Keep In/Keep Out commands to extract the power lines you wish to draft, view the powerlines in 3D View:

 

Point Cloud only view in 3D

 

Point Cloud Data after Region Classification, Turning Regions off in View Filter, and using Keep Out to Remove Points

 

Using the Polygon Select tool, create a selection polygon around one powerline at a time to select each point on the powerline.  Open the Best-Fit Line command in the CAD tab (licensed by the Advanced Drafting module) and match these settings:

 

Best-fit Line Command and settings

 

Click OK and repeat for the other two power lines.

 

Finished 3D Linestrings

 

Once completed, you’ll have three 3D linestrings for use in your TBC deliverable!

 

Station View with Power Lines Drafted

 

Special thanks to Chad Lewis for the data set and workflow suggestion this week!

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