topic Re: Create a line at constant grade? in Mining Questions

Create a line at constant grade?

dougmorford — Thu, 21 Feb 2019 00:43:36 GMT

I'm wondering if Arc Pro or Arc Map have a tool which allows you to create a line using an elevation surface to automatically choose a constant grade path. I've found the spatial analysis distance tools, but it is not clear that any of those tools would do this, or which one is appropriate. It seems those tools are for creating rasters for path selection.

With the tool I'm looking for, I'm thinking you'd click your starting point, then the next vertex creation would create a line at constant grade, making the line weave in and out of draws and ridges. It seems like a no brainer that arc would have a tool for this, but I can't find it. Obviously, this would be for road design. It would be pretty handy now that lidar is prevalent.

Re: Create a line at constant grade?

DanPatterson_Retired — Thu, 21 Feb 2019 05:11:23 GMT

The trouble with grade or anything involving slope is that the methods of determine slope use a 3x3 moving window in their calculations. The software has no concept of moving across a natural slope at an angle to maintain a constant grade of traversal.

Re: Create a line at constant grade?

dougmorford — Thu, 21 Feb 2019 06:34:30 GMT

I would think each moving window calculation could allow determination of a 3d azimuth tangent to the surface that matches a defined vertical plane slope. Doing that, you'd at least be able to create a line at a defined grade. At that point, finding the correct grade to get to a destination might be a guess and check game.

Do you know if there is a tool for creating a line at a defined grade and distance? Even that would be immensely useful.

Re: Create a line at constant grade?

DanPatterson_Retired — Thu, 21 Feb 2019 12:37:06 GMT

You can roll out your own kernel if you want for the first.

Focal Statistics—Help | ArcGIS Desktop

or for more complex kernels, you could use numpy or scipy.ndimage

Idon't work with the 3d stuff in map or pro, but the 3d analyst has a few tools that may be useful

Interpolate Shape—Help | ArcGIS Desktop

Add Z Information—Help | ArcGIS Desktop