Selecting the Right Base Plane
Choosing the appropriate base plane will help you ensure that you are recording accurate measurements.
There are three base-plane options available for volume calculation; Linear Fit, Lowest Point and Triangulated.
Linear Fit (formerly "Best Fit") defines the base plane by fitting a perfectly flat plane, in 3D, through the chosen edge points. It's great for stand-alone stockpiles in most situations on flat ground.
Lowest Point calculates a horizontal base plane from the lowest edge point. This option is more suited to calculate the volume of benches or stockpiles on flat ground in bins, or where there are neighboring piles right up against each other. The lowest point base plane is very sensitive to the vertices of the volume annotation being created and assumes the ground under the annotation is very flat. If the ground is slightly sloped then, this can distort results.
Triangulated joins up all of the edge points to create a 3D surface under your stockpile. This is perfect for long thin stockpiles, or for large stockpiles over 0.5 acres in size.
Custom Elevation base planes are now available! Simply input the known elevation of the area below the stockpile and the algorithm will do the rest.
What if I am comparing volume differences over two maps?
Linear Fit baseplanes (and lowest point, triangulated, custom elevation), are all estimations for a baseplane when you have no other data. These baseplanes can vary from map to map with very minor changes, especially if numerous points are selected to outline the stockpile. While these are great for one-off measurements with no other data, they’re not as accurate when comparing maps over time.
We’d recommend updating the baseplane to compare it to an older map, which will use the same polygon with the exact same points and will show the difference between the two volumes, as opposed to using the estimated baseplane.