Post-processing loop closures results

Check The Default Settings ?

Right from the box the software may have different goals, one setup for static the other for RTK massaging. The best you can do is match those settings from software to software.

Internally the softwares have different settings to handle less than perfect data. I know my Ashtech Solutions and GNSS Solutions can give me very good solutions from data that will not be accepted by OPUS-S or OPUS-RS.

Paul in PA

Other settings to watch out for in order to keep an even playing field between the two processing applications are the elevation mask angle, ephemeris type, antenna model set, and tropospheric model.

This information helped, thanks. I did verify the parameters and uploaded the precise ephemeris from the government's website. I am working with GNSS and TBC.

In GNSS, my main problem is a bust in elevation data on some of the observations (first order geodetic monuments). Being rather large, 10-12 cm's, it appears to be a blunder caused by the antenna model, a Trimble GPS5800. Not too sure what I am doing wrong but I am pretty sure that it is an operator error. This problem is not encountered in TBC. Field equipment is GPS4600LS (2) and GP5800 (1).

I like GNSS solutions, great software. The information and menus are easy to access. No information overload. Straight to the point. The needed information is right there on the main screen or not too far. Export options appear to be limited. I had to export to CRD to get an ascii file out. Again, probably lack of experience.

TBC is fairly easy to learn. There are definitely some useful improvements. Aside from the price, I do not see how experienced users of TGO could find it difficult to switch over.

> This problem is not encountered in TBC. Field equipment is GPS4600LS (2) and GP5800 (1).

Georges, if you have no problem importing DAT files from a 4600LS into TBC, would you mind posting the details of how you did it, i.e. from survey controller or receiver and which software was used for the receiver download? My experience has been that the point names get lost when stop-and-go kinematic DAT files from a 4600LS are imported into TBC and I'd like it not to be the bug in TBC that it appears to be.

Hello,

I only tested TBC with static data so far (1hr + sessions). No data collector.

Data was recorded on the receiver and then downloaded with the old GPLoad utility for the 4600's, and the data transfer utility for the 5800. The DAT files were then imported into TBC using the import command. At the check in time, I renamed the stations, instead of keeping the automatic names created by the receivers. I used the same import procedure with RINEX data files (different test).

The computer used for the downloads is a different computer than the one with TBC.

Antenna Models ?

Antenna model data will become more of a problem with transitioning from the relative NGS antenna models used for years to the newer absolute antenna models

The best way to check your antenna models is to swap your various antenna type receivers over known points. Verify any antenna data on the "odd man out" test.

Paul in PA

> At the check in time, I renamed the stations, instead of keeping the automatic names created by the receivers.

> The computer used for the downloads is a different computer than the one with TBC.

That sounds exactly like what I did, i.e. downloading the receivers on one machine, "checking them in" to generate the DAT files and then trying to import the DAT files onto another machine running TBC. The 4000ssi static data did import with station names, but not the 4600LS stop-and-go DAT files.

Antenna Models ?

Thanks Paul,

I think my problem is somewhere within GNSS. I do not see what can cause this vertical bust. It appears to be related to the baselines observations with the GPS5800 antenna.

Here's a bit of results. Same methodology used for both software. Import, process, adjust with CCM36 (Horiz.) and 83T202 (Vert.)

ID Publ. TBC GNSS RTK QC
66T004 169.66 169.68 169.80 169.66
66T006 165.14 165.16 165.27
76T029 143.14 143.13 143.11
83T202 153.67 153.67 153.67
CCM36 n/a 161.30 161.30 161.30
NAIL n/a 152.46 152.33 152.45
TNGL n/a 152.75 152.61 152.74
YK-CACS 181.00 180.98 181.11

Publ. means published.
Truncated to 2 decimal places for clarity.

I will have to figure out what I am doing wrong, I like GNSS Solutions.

Antenna Models ?

If the heights shown are in feet, it looks like it is switching between the bottom of the antenna mount and phase center.

Antenna Models ?

Units are metres

It seems to be something like that, an offset issue.

Hello,

As a check, I did a quick survey in PPK mode with legacy equipment. I imported the two DAT files from the 4600 receivers and the DC file from the TCS1. TBC processed the data as expected, including bringing in the point ID's of the rover observations.

Good luck,

Georges

> I imported the two DAT files from the 4600 receivers and the DC file from the TCS1. TBC processed the data as expected, including bringing in the point ID's of the rover observations.

So, were you logging the rover observations to the TSC1 and the base to the receivers?

Send Files To Others To Check Your Numbers

My email is in my profile, send me RINEX files, "o" and "n".

Paul in PA

If Georges is doing the way I've done it, I connected the data collector to the 4600LS receiver to start the survey, then disconnected it after the receiver was logging. If I recall correctly, the point name, antenna height, etc were hardwired into the raw file. It has been quite a few years, so my recollection might be faulty. Move to the next receiver and repeat.

> If Georges is doing the way I've done it, I connected the data collector to the 4600LS receiver to start the survey, then disconnected it after the receiver was logging. If I recall correctly, the point name, antenna height, etc were hardwired into the raw file. It has been quite a few years, so my recollection might be faulty. Move to the next receiver and repeat.

Scott, if you're thinking of how the 4600LS used as a base receiver is started, yes, that's the way it works if you're logging observations to the receiver's memory. For the stop-and-go kinematic rover, the data collector would remain connected to the receiver regardless of whether the observations are logged to the 4600LS or the data collector.

After losing a day's work in some data collector amnesia misadventure years ago, I haven't logged observations to a data collector since because the receiver's memory is more reliable and downloads are faster, but if it makes the difference between TBC being unable to process the DAT file and being able to, I'm willing to consider changing that habit.

Send Files To Others To Check Your Numbers

Hello Paul,

Thanks for the offer. I only see a send message box, no e-mails/no attachments options.

Georges

I just set up the base receiver over the monument, no data collector attached. Surveyed a few points with the rover and data collector, recording DAT file on receiver.

Imported 3 files in TBC (2 DAT's and 1 DC)

Entered the HI and coordinates of the base point on the computer.

> I just set up the base receiver over the monument, no data collector attached. Surveyed a few points with the rover and data collector, recording DAT file on receiver.
>
> Imported 3 files in TBC (2 DAT's and 1 DC)
>
> Entered the HI and coordinates of the base point on the computer.

If you were logging the DAT file of the rover to the receiver, what was there to download from the TSC1? Or was the rover logged to it rather than the 4600LS?

In this case, the DAT file is recorded on the receiver. That's an option in the configuration of the survey style. I guess the DC records the rest.