Importing terrain data from drone survey

[LevisL]

I am working on a condo renovation project consisting of multiple buildings on a sloping site with retaining walls, etc. I haven't been able to locate an existing survey of the property and the condo association has not had any luck finding a surveyor willing to do one in a timely and cost efficient manner. Anyway, to make a long story short, I have someone willing to take an aerial drone survey of the site. They typically do field elevation mapping for farmland, so the drone has the capability to capture elevation data.

 

I'm looking for advice/tips/best practices from anyone who has collected terrain elevation data in such a way to use in Chief.

- Looking in Help and the Reference manual, it looks like we have a few options for importing data in a few different formats? Which one works better? txt? dxf/dwg?

- Do you edit the data in other software or apps/websites prior to importing into Chief?

- How do you handle the elevation data of non-terrain objects that the drone captures, like buildings, trees, etc.?

- Any other tips or anything I should know/watch out for?

 

Thanks in advance,

[robdyck]

The only thing that comes to mind right away is that I would suggest some experimenting in a saved version of the file. When I've imported surveyors contour maps and converted them to elevation lines, the terrain has generated far too many elevation points and it really slows the the file down. I've had the same experience when importing terrain data from a survey. What I prefer to do is use simplified methods and manually enter the elevation data in a way that I know will keep my file operating efficiently but still represent the terrain accurately. 

Alternatively, I may import the data in a separate file and then create a symbol that I can use for visual reference in my main plan file. But I've found that importing data, then cleaning it up / simplifying / deleting / altering for the terrain to generate efficiently in Chief can take longer than placing elevation points / lines / regions manually.

[LevisL]

Thanks Rob. Yeah I was thinking along the same lines. I was planning on importing the terrain in a blank file and copying the buildings over once I got the terrain elevation cleaned up to where I'm happy.

[Gawdzira]

Sounds a lot like "Auto Topo". When I used to work with a surveyor and we just wanted to go get lunch, we would drive by and say to each other "looks like a hill".

[LevisL]

On 11/15/2023 at 8:13 AM, Gawdzira said:

... we would drive by and say to each other "looks like a hill".

 

Haha. Unfortunately that won't be good enough for this project! If I was just doing work on the buildings, I might eyeball it, but the old wood retaining walls on this site (and there's a few of them) are starting to show their age and need to be replaced, so knowing the elevations will help me a lot. And that's just one of the site improvements they want to make on this project.

 

Anyway, we're going out to fly the drone later today, so I'll have the elevation data. How I'm able to get that data into Chief will be the next challenge! I'm anticipating some hiccups, but hopefully nothing too bad. I have the booze ready in case I need a stiff drink or two after this!!