One of the primary uses of Virtual Surveyor is to create lightweight CAD models. Creating a lightweight Triangulated Irregular Network (TIN) Surface from your elevation terrain is often the first step in many surveying workflows. Within Virtual Surveyor, a surface enables you to calculate volumes, display contour lines, and create Cut/Fill maps. It is also possible to export your 3D surface to a common format for usage in other CAD software programs.


Overview


Import Your Drone Survey Data

Drag and drop your drone survey dataset (Orthophoto + DSM) into the project view to create a Terrain State. If you have more than one drone survey of the same area, use the Terrain State feature to manage them individually (Only available in the Peak plan).



Create a Boundary for Survey Items

Create a boundary to define the area where you want to create the surface. 

  1. Select the Boundary tool from the HOME tab and create a boundary around the area you want to create a surface. 
  2. With the boundary selected, go to the SELECTION-TOOLS tab and click Densifyto drape the boundary onto the elevation model. 
    1. For this situation, it might be best to densify the vertices every 20 ft. (6 m).



Create a Q-Points Survey

Create survey points within the boundary using the Q-Points feature available in the HOME tab.

  1. Select the Boundary.
  2. In the Point Grid section, change it to Q-Points and set the Elasticity to 2 ft. (0.6 m).
  3. Click Point Grid.

The system plots points across the terrain boundary everywhere there is a shift of 2 ft in the elevation. 



Clean Up Points

Clean the surface by deleting or moving points and survey items that land on worksite equipment, trees, vegetation, etc. 


Q-Points is a feature that generally works best over areas of dirt or where the ground is clearly visible. The fewer equipment and vegetation that are captured on the worksite, the better the Q-Points feature works. If there are a lot of obstacles on the ground of the worksite, you might be better off using the Low-Pass Point Grid feature.


Create the Surface as a Triangulation

  1. Select the boundary. 
  2. In the HOME tab, go to the Toposurface group and click Triangulate Within
  3. The TIN surface is created.



Check and Edit the Surface TIN

Some TIN segments may need to be removed. 

  1. Select the TIN.
  2. Use the Remove Triangles tool available in the SELECTION TOOLS tab to clean undesired TIN lines from the surface.


Surface creation is often an iterative process. If you are not satisfied with the accuracy of the surface model, you can always delete it, add more survey items, then recreate the TIN. 


Display the Surface as Contour Lines

By default, surfaces display as a TIN upon creation. However, you can hide the triangles and show the TIN as contours. You can also change the Styling using the surface style settings in the SELECTION TOOLS tab.


To see the TIN as Contours:

  1. Make sure the TIN is highlighted.
  2. Go to the Styling section in the SELECTION TOOLS tab.
  3. Click Hide TIN.
    1. The Contours are now visible.  



Export the Surface 

If you want to use the surface in a CAD software program, export the surface as a .dxf, .xml, or .shp file. The Export feature works with the concept of "what you see is what you get" or "WYSIWYG". Whatever contour lines and/or survey items are displayed or active are exported along with the surface TIN.   


Tips & Tricks

  • If survey specifications only require a line survey, take a look at this article for ideas of how to quickly create break lines.