Hi all!
I'm exploring a new way to handle NRTK data and I'm trying to figure out if it is possible to form a direct link from a VRS back to a CORS (the nearest one probably).
You could theoretically compute a baseline from the VRS to the CORS, but there may be a dependency issue as the VRS was derived from data from that CORS (but also from others). Is doing this allowed?
Has anyone tried anything like this before?
Thanks,
Tom
If you are already connected to a VRS Network and?ÿ receiving corrections what would you gain by doing it?
I'm looking to throw the NRTK observations into an adjustment. Normally they are treated as point observations, but they can actually form a network connected by the VRSs. So far I just have baselines from VRS to my observed stations but I would like a connection to the datum.
I understand what you are trying to do but its not going to be possible with a Virtual Reference Station. In as much as it exists at all, the station does not exist outside of the session.
This is one of the main advantages claimed for Leica's MAC system (Master/Auxiliary Concept). The vectors are all from a real station (nearest CORS), but the corrections supplied are calculated using a network of stations, not just the nearest.
We are running Trimble??s Pivot and it allows you to manually generate and position VRS. It generates RINEX (or similar) data as if it were a real station and these appear as intervals in LGO, just like a normal observation.
Given that we can do this, I??m sure there is a way to access the RINEX data generated from automatic VRS. Although the intervals do not appear in LGO..
In Trimble Access you have the option to store vectors (it's the default); the software calculates delta x, y, and z to the nearest CORS. As long as you also store QC1 & QC2 you can use it in an adjustment. I'm also on a Trimble VRS network, not sure if that matters or not.
In Trimble Access you have the option to store vectors (it's the default); the software calculates delta x, y, and z to the nearest CORS. As long as you also store QC1 & QC2 you can use it in an adjustment. I'm also on a Trimble VRS network, not sure if that matters or not.
We have been doing this for 13 years, it works very well for repeatability as long as you are on the same tectonic plate or can adjust.?ÿ We are also Trimble.
Interesting, I??ll look into this. Thanks for your help!
I didn't give the entire story.?ÿ We actually switched to Carlson a few years ago and while most of our collection is Trimble some is Carlson converted to Trimble.?ÿ In Carlson we specify the mount point and collect the vectors and quality data and then I wrote an Excel?ÿ sheet that converts it to a Trimble .dc file.?ÿ I use this sheet to also convert old files that were collected off of the wrong tectonic plate to the one I want it on.
In Trimble Access you have the option to store vectors (it's the default); the software calculates delta x, y, and z to the nearest CORS. As long as you also store QC1 & QC2 you can use it in an adjustment. I'm also on a Trimble VRS network, not sure if that matters or not.
When using a VRS. I thought the vectors stored were to the VRS, not the CORS. (In Access).
Maybe it's changed
VRS creates an imaginary receiver that is very close to your work site. For this imaginary receiver?ÿ an imaginary observation file is created from?ÿ adjacent CORS observations. This imaginary receiver becomes your virtual RTK/FTK base. From, this imaginary base your various rover positions are calculated from very short vectors. If your office software is typical you can create a RINEX file for your VRS point and submit it to any set of OPUS CORS you want. I have done that in the past when I mainly used L1 only receivers in the field. It is less necessary to do now, but it can help you to understand the quality of your field work. If your software is creating multiple VRS points, doing that extra work for multiple short files is much less useful.
Paul in PA
Great timing for this post.?ÿ I just figured out that I needed to change settings in Trimble Survey Styles from Positional to Vectors in order to make use of the PBS (physical base station) data being sent from NC's VRN.?ÿ
While I can understand why I should store vectors, can anyone explain a situation in which it would be better to store positions?
When Trimble first came out with VRS the vectors were related to the virtual base, you even saw it in the collector. My understanding is that there was a demand for the VRS shots to be tied to an actual reference station. My understanding is that the deltas to the nearest physical CORS are back calculated but the positions are still derived from the VRS.
