How to use the Surface Cleanup tool

 

Introduction

Are you trying to do 3D measurements, but obstacles are blocking your view? This article will teach you how to use the Surface Clean-up tool to remove those objects from your measurements.

To show you how it works, we'll take a look at the first example: removing a conveyor belt to enable accurate stockpile measurements.

An example of the problem

Before we start explaining the solution, let's first take a look at what the problem looks like. You want to measure the volume of a stockpile, but a conveyor belt is hanging over it. This means the volume between the stockpile and the conveyor belt is included in the result distorting your measurements.

Using the Surface Clean-up tool

Start by creating an annotation around the conveyor belt to mask it out. You can create a polygon annotation using the Annotate/Measure menu:

Give a name to the annotation and enable the Surface Cleanup tool:

Once you save the annotation, the conveyor belt will be masked out of your measurements.

How it works

When looking at the active Surface Cleanup box in the annotation popup, you might have noticed two pieces of information:

• Target Surface: This is the surface on which the cleanup will be applied. For now, we only support a single DSM.
• Surface Type: This is the type of surface that will be used as a replacement. For now, we only support an interpolated replacement surface.

The Surface Typedetermines how we clean up the surface. As we currently only support an interpolated replacement surface, this means we try to mimic the surface by looking at the elevation on the vertices of the polygon that you drew.

Adding more points to your polygon will thus allow us to smoothen the surface even more. Placing the points on specific edges will also allow the replacement surface to follow those edges better. In this example, you might want to place two points on the edge of the stockpile to make sure we don't cut off the corners there.

 

Tips & Tricks

• The surface cleanup will linearly interpolate between the points you draw. This means it's drawing straight lines between the points you draw to replace the surface. When the surface curves a lot, it's best to place more points, so the surface cleanup will follow the surface better.
• Surface cleanups work for all types of 3D measurements, so surface lengths or elevation profiles will also be them.
• The digital surface model you can download from the Layer Downloads pane doesn't include surface cleanups, it's the original model.