Using Stop & Go in Emlid Studio to correct GCPs with PPP output

Emlid Studio Stop & Go with Emlid Flow
1

Hi Emlid Community,

I am seeking clarification with regards to processing a Stop & Go survey with PPP data. I do not have an NTRIP account, CORS stations will always be too far away, and most of my surveys will need to be completed in a day, so no possibility in creating my own known base point before capturing survey points.

Here is my field workflow:

  1. I followed the Stop and Go with Emlid Flow set up instructions here: How to log data for Stop & Go with Emlid Flow | Reach RS2/RS2+
  2. My base and rover will record raw RINEX and UBX logs for the duration of my survey. The base will get an average single position for at least 30 minutes before surveying, however, I usually let it run for most of the day to get at least 4 hours of raw logs to send into NRCan PPP service then survey my points with the rover at the end of the day.
  3. I will wait at least a week before sending in the base raw logs to NRCan to obtain my known point for cm level accuracy.
  4. Process the points in Emlid Studio after obtaining my base coordinates from NRCan by using this workflow: Stop & Go with Emlid Flow | Emlid Studio.

However, I am unclear at which point in the above workflow where I would enter my base coordinates I received from the PPP service. In the above document in step 3, it says:
“Set the base coordinates. By default, the RINEX Header Position is used. If you placed your base over the point with known coordinates, enter them manually, including the antenna height.” But I did not use my known coordinates in the field as I did not have my point yet.

In a number of threads, including this one: Post-Processing vs Survey Mode with unknown base position - #7 by EBE111057 , says that, "after you get the precise base position from the PPP service, there are 2 options: (1) calculate the shift from the base coordinates you averaged in Base mode and add this value to all GCP coordinates (2) Using stop & go processing.

So I want to try the Stop & Go Processing to correct my GCPs to account for the shift after getting my PPP coordinates. I usually just calculate the shift in excel, but the less moving parts the better to minimize human error. So my question is at what point in the Emlid Studio Stop & Go workflow do I enter my NRCan PPP coordinates? All workflows are for when you already have a known point and I get kinda confused of what to do for my RTK/ PPP hybrid workflow.

Thanks!

3

Hi Emma,

Welcome to our forum!

If you start Stop&Go processing after you received precise coordinates from NRCan, you just need to input them manually into the Base tab of Emlid Studio. You don’t need to calculate the shift in Excel, the resulting points will be calculated with respect to the base coordinates from NRCan.

The additional calculation in Excel is needed if you start processing before obtaining the NRCan solution. In this case, your base coordinates will be taken from the RINEX header, and those coordinates are of meter accuracy.

5

Hi kirill.pavlyuchuk,

Thank you very much for the reply.

So from what you said here: “The additional calculation in Excel is needed if you start processing before obtaining the NRCan solution. In this case, your base coordinates will be taken from the RINEX header, and those coordinates are of meter accuracy.”

  • There is no way to process Stop & Go in Emlid Studio if you receive the NRCan solution after the Stop & Go Survey? So Stop & Go is not possible with obtaining the solution after? Wouldn’t there be some way I can enter my NRCan solution in Emlid Studio and do everything in post?

From this post by elena.riazanova, she said that you are able to process AFTER getting the PPP solution: Post-Processing vs Survey Mode with unknown base position - #7 by EBE111057

Please clarify the difference in what you said and what elena said.

Thanks!

7

There is. This is what I explained in the first paragraph of my response:

So you just wait for the precise output from NRCan and process in Stop&Go using the coordinates from NRCan.

9

My apologies! I was reading it wrong and thought you meant to enter the coordinates in Emlid Flow before surveying the points.

Thank you for your patience and your help.

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