Repeating site survey

[last6]

Hi,
Looking for a little advice please. I’ve been asked to carry out surveys of a site on a fortnightly basis as a trial and learning experience. I’m curious to know the most efficient way of doing this to ensure consistency in data collection for historical review.
Is it as simple as setting my base station on the same known location and laying shooting gcps/checkpoints on each return visit or should I try to keep the gcps/checkpoints in the same place? Hope that makes sense and thanks in advance for any advice, thoughts and info.

 

[jaja6009]

What are you using for a Base? DRTK? Emlid?

Assuming you have an Emlid or DRTK 3, I would create a known point for your Base. Sit on it for 12 hours, run PPK or submit to OPUS. You now have your point. Setup your Base on this point for each flight and use this for your ground Rover.

If possible layout permanent Control Points, both GCPs and Check Points. Spread them out well and make sure to have one at the highest and lowest elevation points.
Measure these points using PPK from the logs from your ground Rover and the Base. Fly your mission, get your logs and PPK that data using Red Tool Box or Even DJI Tera's PPK option.
You can also use RTK from the Base.
If you can't have permanant Control Points it will still work as long as you have nice spread out Control Points since you are using corrected data and Control Points.

 

[last6]

What are you using for a Base? DRTK? Emlid?

Assuming you have an Emlid or DRTK 3, I would create a known point for your Base. Sit on it for 12 hours, run PPK or submit to OPUS. You now have your point. Setup your Base on this point for each flight and use this for your ground Rover.

If possible layout permanent Control Points, both GCPs and Check Points. Spread them out well and make sure to have one at the highest and lowest elevation points.
Measure these points using PPK from the logs from your ground Rover and the Base. Fly your mission, get your logs and PPK that data using Red Tool Box or Even DJI Tera's PPK option.
You can also use RTK from the Base.
If you can't have permanant Control Points it will still work as long as you have nice spread out Control Points since you are using corrected data and Control Points.

Wow thanks for the quick response.
I should mention that I live in Northern Ireland. I have one DRTK 3 unit acting as either base or rover. I also have access to an NTRIP subscription. Maybe not just as straight forward as I first thought.
Thanks

 

[jaja6009]

Wow thanks for the quick response.
I should mention that I live in Northern Ireland. I have one DRTK 3 unit acting as either base or rover. I also have access to an NTRIP subscription. Maybe not just as straight forward as I first thought.
Thanks

With NTRIP it got easier.

1. Make a known point using the DRTK 3 while receiving corrections. Sit on this point for 12 hours to get it as tight as possible.
2. Use the DRTK 3's new and improved Rover mode to collect your Control Points while receiving corrections. Sit on each point for at least 1 minute if your NTRIP base is less than 20 km. Sit on them longer with a longer baseline.
If you can setup permanent control points it would be better, but if not it is not a game changer.
3. Place the DRTK on the known point and have it send corrections to your drone.

With corrections to the drone and GCPs, you should have nice tight data.
Use your Check Points to assess your data.

PPK will be more accurate, but I have made some pretty tight data with RTK as long as your baseline to your base is short.

 

[last6]

Thank you so much. Really appreciate your help. I’ll certainly let you know how I get on.
Such a good forum.