RTPK

Shawn Billings

Shawn Billings
5PLS
RTPK stores the RTCM cotrections and then statically post processes the data. If there aren't corrections then the data could be post processed with DPOS after the base data is downloaded.
The data can also be post-processed by RTPK in the points screen after the base data is downloaded. This is helpful for several reasons: 1. The processing parameters can be changed and the data reprocessed. This means that a 10 minute rover file could be processed as 10-1 minute sessions, 5-2 minutes sessions, 2-5 minutes sessions, etc. 2. Processing can be done without internet service. The RTPK processor is onboard, unlike DPOS which is cloud-based. This is helpful if you are working in a location where you don't have cell service, so you log raw data for each of your rover points, then download the base raw data, and process while still on site.
 

Matt Johnson

Well-Known Member
5PLS
I wasn’t aware or had forgotten that RTPK could pull data from the base file after it was downloaded.

One advanced from processing from the points screen is that the filtering of the base file is done over the entire file rather than being split into sessions as is done when the data is being collected. I found this leads to good solutions when you don’t get while processed in real time.
 

TonyC

Member
The data can also be post-processed by RTPK in the points screen after the base data is downloaded. This is helpful for several reasons: 1. The processing parameters can be changed and the data reprocessed. This means that a 10 minute rover file could be processed as 10-1 minute sessions, 5-2 minutes sessions, 2-5 minutes sessions, etc. 2. Processing can be done without internet service. The RTPK processor is onboard, unlike DPOS which is cloud-based. This is helpful if you are working in a location where you don't have cell service, so you log raw data for each of your rover points, then download the base raw data, and process while still on site.
How does the processing of RTPK differ from just regular PPK? If I took both rinex observation files from the base and rover and ran it through trimble business center would I get the same result as doing it on the LS+?
 

Wes Hand

Active Member
Anybody got thoughts on why rtpk it the wide open is not returning a good result? This is occuring more frequently than in the past. I have cleared NVRam on my T3, etc. I will take a 60 second shot in the open on critical points and usually the rtpk will agree but lately I'm seeing too much red in the points screen signifying a disagreement in rtk/rtpk. I'm having to look through my points and I'm having to post process several points with some that return with a fix that agrees with the rtk...but way too many will say Sucess! and still be off by 10 feet. My post process interval is set to 60 seconds by the way and I will change it to 20,30,40 with a shot thats only got 60 seconds of data but its not helping with the points like I have posted below.

Notice in the screen shot the disparity in the rtk & rtpk. Furthermore for my Sats under rtpk I only have a few satellites. Why? This shot is in the wide ass open.

PROCESSED-POINT-INFO-SCREEN_20230509-07.04.27.png



The screen shot below is after I post processed the selected point. It told me Sucess! but its still not close to being correct. The sats changed as well. Can someone explain why the static file has significanly less sats available in the solution.

PROCESSED-POINT-INFO-SCREEN_20230509-07.16.35.png
 

Shawn Billings

Shawn Billings
5PLS
Anybody got thoughts on why rtpk it the wide open is not returning a good result? This is occuring more frequently than in the past. I have cleared NVRam on my T3, etc. I will take a 60 second shot in the open on critical points and usually the rtpk will agree but lately I'm seeing too much red in the points screen signifying a disagreement in rtk/rtpk. I'm having to look through my points and I'm having to post process several points with some that return with a fix that agrees with the rtk...but way too many will say Sucess! and still be off by 10 feet. My post process interval is set to 60 seconds by the way and I will change it to 20,30,40 with a shot thats only got 60 seconds of data but its not helping with the points like I have posted below.

Notice in the screen shot the disparity in the rtk & rtpk. Furthermore for my Sats under rtpk I only have a few satellites. Why? This shot is in the wide ass open.

View attachment 13081


The screen shot below is after I post processed the selected point. It told me Sucess! but its still not close to being correct. The sats changed as well. Can someone explain why the static file has significanly less sats available in the solution.

View attachment 13082
That's very curious. The satellite count is definitely pointing to some problem, but I wouldn't put it on the base, most likely, because the base was able to provide good corrections for the RTK solution.
 

Shawn Billings

Shawn Billings
5PLS
How does the processing of RTPK differ from just regular PPK? If I took both rinex observation files from the base and rover and ran it through trimble business center would I get the same result as doing it on the LS+?
You would get a slightly different result because post processing software uses estimations for things like tropospheric delay. Different developers will use different estimations. Also different software will make decisions when selecting which data to use in a multipath environment and how to weight some of the data.
 

nusouthsc

Active Member
Anybody got thoughts on why rtpk it the wide open is not returning a good result? This is occuring more frequently than in the past. I have cleared NVRam on my T3, etc. I will take a 60 second shot in the open on critical points and usually the rtpk will agree but lately I'm seeing too much red in the points screen signifying a disagreement in rtk/rtpk. I'm having to look through my points and I'm having to post process several points with some that return with a fix that agrees with the rtk...but way too many will say Sucess! and still be off by 10 feet. My post process interval is set to 60 seconds by the way and I will change it to 20,30,40 with a shot thats only got 60 seconds of data but its not helping with the points like I have posted below.

Notice in the screen shot the disparity in the rtk & rtpk. Furthermore for my Sats under rtpk I only have a few satellites. Why? This shot is in the wide ass open.

View attachment 13081


The screen shot below is after I post processed the selected point. It told me Sucess! but its still not close to being correct. The sats changed as well. Can someone explain why the static file has significanly less sats available in the solution.

View attachment 13082
Wes,
We had a similar experience recently. RTPK would fix on the first process with a difference similar to what your seeing. but then would fail the 2nd 3rd, 4th, and maybe get a solution on the 5th process. This was in all environments, various baseline lengths, and over about 1 month. It finally got so bad we were considering sending the unit in for service. Finally Adam Sam Glenn helped me figure out it was due to a corrupted coordinate system. I deleted all projects from the LS and deleted all ground systems and it corrected it.
 

Shawn Billings

Shawn Billings
5PLS
That's interesting. It makes me wonder if the Factory Recovery, available on the boot up screen (press home key at the prompt before the splash screen) might help. It does not affect user data. I know it seems to clean up a lot of issues likely due to some corruption. @Steve Hankins recommends it often with great success for various problems.
 

nusouthsc

Active Member
That's interesting. It makes me wonder if the Factory Recovery, available on the boot up screen (press home key at the prompt before the splash screen) might help. It does not affect user data. I know it seems to clean up a lot of issues likely due to some corruption. @Steve Hankins recommends it often with great success for various problems.
Shawn,
I failed to mention that we did a factory reset as you described with no effect.
 

Shawn Billings

Shawn Billings
5PLS
Shawn,
I failed to mention that we did a factory reset as you described with no effect.
Josh, you gave what worked which was the important thing. I was hoping the Factory Recovery would get it, but it's nice to know you already tried it, even if it didn't work.
 
Shawn:

Because I work in an area without cell service, on a new job, I set up the T3 on an autonomous coordinate, take shots with the LS+ rover and then take the raw data back to the office to use DPOS to reduce it to SPC's. Normally, the autonomous points shift about one foot in position.

Are you saying above that, with RTPK (which I have), I could do the same reduction of raw data in the field without having a connection to the internet? If so, are there instructions somewhere online explaining how to do this?

Thanks!
 

Wes Hand

Active Member
Glen,

You have to have an internet connection to send project to DPOS to correct up the base to a known SPC......maybe not what you were asking but if you lose cell or radio (communications icon will be red) in the field, you can still gather raw data for that point albeit autonomous. You can then manually select that automomous point or multiple for post processing in the field but you have to download the base data first. Once base data is downloaded, the option to do so is under additional actions maybe 3rd page under rhe points screen. The work flow is cumbersome but it beats moving a base to get a couple of shots if the base communication goes down. You will not know if you have a good shot until you post process so I will locate critical points multiple times for at least 2 minutes to make sure I have enough data. If heavily wooded I camp out for several minutes....you can even change up your post processing interval in your action setup as well. I have had 6 minutes of data not return a fixed solution being processed at 1 minute intervals but then I changed it to 20 seconds and I got 6 intervals at 20 seconds in agreement. Crazy powerful stuff on the LS if you know where to find it.
 

giulio

Member
could you explain the steps to set the post processing intervals, I didn't know it was possible, I pressed the post processing button on the point screen and sometimes this doesn't provide solutions. Thanks
 

Wes Hand

Active Member
The option to change this processing interval is under your action setup. So lets say you post process and it fails and now you want to change up the processing interval....

Step 1...go to your action setup

ACTION SETUP.png



Step 2...select rtpk usage and the following screen appears. At bottom right you see points screen post-process interval
and this is where you change the process interval.

RTPK USAGE.png



You then have to back out and post process again. If it fails again with no solution you have to go back under the action setup and rtpk usage and select another interval. I have seen 3 - 20 minute occupations with no agreement between the 3 and we kept changing the process interval and ended up with 3 fixes via post processing.

I personally think this is way too hidden and time consuming but nevertheless its a powerful tool. I'd like to see under the points menu the option to post process and select the various intervals all under one window...hint hint.
 
Wes:

Thanks for the detailed answer. Just to be clear, it sounds like the onboard reduction of a point with the downloaded base file will only 'solve' the location of the point in relation to the base. If the base is autonomous, the whole raw file will need to be processed by DPOS to translate it to SPC. Is that correct?
 
Top