RS3 Base/Rover Survey Accuracy in ArcMap

Relative noobie with RTK survey…

My archaeological outfit is attempting to use a RS3 base/rover pair to survey in utilities on our museum’s property. After updating firmware and running through the setup (following Emlid’s Youtube videos), we set up our base on a treeless lawn. We did not use a known datum. Once the base and rover were connected, we tested surveying in marked utility lines. The Survey job was created using our state’s NAD83 projection. After exporting the job as a .csv, we dumped the X,Y data into a NAD83-projected ArcMap and added aerial imagery that colleagues have used to great effect. The points from our survey were roughly 13 ft. away from where they should have been.

We also took our RS3 pair to a known geodetic survey marker and set up the base over the survey disk. The point collected by the base was roughly 6 ft. off from the datum’s registered position.

I’m sure we’re doing something wrong (at least one thing!), but we’re struggling with a workflow that will take us from setup to data collection to GIS integration. Is there a resource(s) I should look at to help us sort out our issues? Thanks very much in advance for your help!

How did you establish the base’s reference position? It sounds like it was a Single-type solution?

The rover stated that we were Fixed when we were collecting our point data. Is that what you mean?

Nop. The rover position is relative to the base position. So if the base reference position is off, your rover is off.

You need to either use a well-known point, and enter those coordinates into the base, or establish the Base position with an RTK service, or beforehand using postprocessed data.


That makes much more sense, thanks. We’ll give the geodetic marker another try and enter the point before doing some test survey in the area. Thanks for the clarification!

Hi Travis,

Welcome to the community!

I agree with @wizprod about checking the base reference position first.

Also, please ensure you set your project in Emlid Flow on the same datum as your geodetic marker.

Let me know how it is going.