Emlid

Post-Processing


(Luis Galina) #1

If I want to do a stop & go measurement with post-processing, I disable the LoRa and configure a single measurement?


(Timmyd) #2

the LoRa is used to connect one Reach RS to another (ie connect your Rover to the Base unit) and receive RTK corrections. So you may or may not use the LoRa connection but the LoRa connection itself has no bearing on doing a stop and go survey. If you are doing PPK for your Stop and Go then it does not matter whether you used RTK or not. The LoRa would be just one means of receiving the RTK correction data.

I use third party software to process stop and go surveys in the ReachView app but I am hoping that someday soon someone or Emlid will do a video with very detailed instructions on how to post process a survey using RTKLib.

Christian has been doing ALOT of stuff so maybe we should setup a tip fund for him to make a video as he uses RTKLib :moneybag::moneybag::money_mouth_face:


(Luis Galina) #3

Timmy I have learned to do postprocessing thanks to Christian. Basically with the help of the CSV and the times, the postprocess with Rtklib is done. Now I can use my base and my rover without lora correction, but how do I configure the rover? float? or single? to then calculate in rtk


(Timmyd) #4

Christian has helped alot of folks! I assume you are speaking of the [BASE MODE] section. I have mine set to Average Single. Float and Fix will not apply because you are not doing RTK between your two Reach RS units (Base and Rover).


(Luis Galina) #5

Thank you Timmy I mean when I create a project in the rover I just set up a single, is that it?


(Timmyd) #6

When creating a survey (Project) if you select Single then it will default to 10 minutes per point. However, you can accept the point before the 10 minutes. I would leave them all “unchecked”. If you are post processing then it is really not necessary to stay at each point 10 minutes provided that you capture the “log” file for at least 30 minutes. Christian did some test the other day and he varied from 3 seconds to 120 seconds at each point. Very little difference between each. when you leave them unchecked and you actually begin the survey, it simply lets you press “Collect” and then you Press “Accept” as soon as you are ready.

You could select the “Single” option box and then set the time to say… 30 seconds (or less). I will defer to others if they disagree with the collection time. I am basing this on the fact that you plan on post processing.

And regarding the 30 minutes, it must be completely unobstructed view of the sky. If you were to walk under trees or go next to a building and have complete loss of satellites, then you would have to start over for a minimum unobstructed log time of 30 minutes. And all survey points must be taken during that 30 minutes. In other words, If you are collecting 10 points. You could not have collected 2 survey points, loose satellites, then start over on 30 minutes and collect 8 more points and then process all 10. All 10 points have to be collected within the start-to-finish log time that is unobstructed.

I do not know how to post process a survey (Reach Rover) using RTKLib so that is what I was referencing earlier that maybe Christian would consider making a tutorial video :slight_smile: or anyone for that matter.


(Luis Galina) #7

What you are describing is a basic principle of a Stop & go measurement and it would be necessary to prove with known points if it works on the fly. RTKlib is difficult at the beginning but very good, I verified a floating point that post processed and that I had already measured two years ago and gave me a difference of 0.007 meters. what is not good the rethink of the ReachView, visually see the sphere in the center does not help and it is lost a lot of time, for us the Land Surveyor is not practical. I’m going to try the Topographer Pro to see if it solves the problem of stakeout. I do not know if you used Timmy? thanks for everything


(Timmyd) #8

I have not used Topographer Pro but I have watched the tutorials that @TB_RTK has done. I don’t do any stakeouts but I understand the latest update (2.16) has many improvements for using stakeouts (not perfect but getting very good). someday i will play with it just for learning it :man_student:

I use the ReachView app to as you say, stop and go and the software I use to post process is EZsurv. @wizprod 's test was using a known point that he had established. Not a Government established known point, so maybe not fully scientific but I think the results were good. He was going to do more testing with it. I’m going to go get parallel :bed: