[Therion] Using 3d Scan Data To Create A Map

[Nick Bairstow]

Hi, Something a bit different for the clever people out there.

I have been playing with some 3d scan data and have attempted to use it to create a Therion map.
Firstly we put created an outline of the cave passage using point cloud software and exported as dxf.
I turned the dxf into a background sketch and drew around it and could output a nice pdf of our cave. Also did a manual scaling. So far so good.

I added a dummy station and gave it entrance coordinates, then exported as a KML model. When I open the output file Google Earth fly's to the correct spot and shows a pin with the cave name but no cave.
My question is , does this fail because we have no survey data, centreline etc and it is impossible to do this or am I missing something.

As an alternative I can export to an esri shp file and run that though Qgis and get what I want but as I am going to attempt to combine the 3 scan data with a several normal disto surveys I would like to see Therion Kml output work if possible to save lots of messing around. (GIS makes my head hurt)

On a side note using the point cloud software I can slice though the scan data on different planes and pick up lots of detail, rocks and boulders etc. Using the dxf/background image method I should be able to get a very accurate representation of the passage. I can hear you all saying what the hell is he doing that for when he could just survey the cave in the normal way! Well the cave is a show cave and absolutely rammed with metal walkways and cables. Disto tests showed wild inaccuracy's so it was looking like the only viable option was going to be to use a Total Station device which we don't have.  We then had a very kind offer to scan the cave, this has proved to be very interesting but drawing a normal map is a bit of a challenge although it seems not impossible.

Any help would be appreciated.

Nick

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