Sorry, Not Accurate
Thank you for this link! Very interesting.
It's interesting that the RTN seems to mop the floor with OPUS-RS. It would be interesting to compare the standard deviation of a points positioned from an OPUS derived base station with local (sub 10km) RTK vectors and direct observation from the TxDOT RTN.
The Triumph-2 has the software internally. I use Javad's Netview software (freeware) to configure the Triumph-2 to connect to my WiFi, and to broadcast a particular correction format over a particular port. In my WiFi router, I have that port set to forward. Once configured, everytime I power up the Triumph-2, it automatically attempts to connect to the WiFi, and once connected (takes about five seconds from power up), it immediately begins pushing corrections through that port.
On the rover side, I select corrections from TCP and provide the IP address of my router and the port which the Triumph-2 is pushing through. There is no additional hardware at the base outside of a configured Triumph-2 and my WiFi router.
The OPUS-RS Issues With That Report...
...were caused by not submitting properly collected data.
OPUS-RS looks for L1, P1, L2 and P2 observables and falls short when you submit some C2 data in lieu of P2 data. OPUS-RS automatically substitutes C1 data if the P1 data was not available but had not been configured to substitute C2 when P2 was not available. The people doing that test should have understood that problem and contacted NGS at that time. That is unless they knew of the problem and were looking to make the test more favorable to another method.
As an alternative one can use the online teqc and parse and merge the observables into a 4 observable RINEX file. I have done that for others and gotten excellent results using other's failed data.
Paul in PA
The OPUS-RS Issues With That Report...
Paul,
The data was collected by NGS as part of the GRAV-D slope validation survey and was not designed with this report in mind. Dr. Dru Smith decided to do this analysis on the data and this paper is the result. The Oregon State project was designed specifically for this type of analysis, so the results should be much more comprehensive. Dr. Smith, et al, just worked with what they had, after the fact.
They Had Sufficient Data, They Did Not Know How To Use It
Paul in PA
thanks
i look forward into reading this one
They Had Sufficient Data, They Did Not Know How To Use It
Paul,
Perhaps you should consider applying for one of the several geodesist positions NGS has recently advertised. It sounds as though their Chief Geodesist could use your knowledge and expertise, which would certainly benefit us all.
😉
They Had Sufficient Data, They Did Not Know How To Use It
Paul,
there is no way you read that article. It explains the problem and how it arose very well. They also found a workaround by using the 48 hour files and breaking them into 20 minute files.
there were still 33,244 RINEX files of exactly 20-min duration, with P2 data, that were successfully run through OPUS-RS without warnings, aborts, or errors. The results of those runs were then compared with the official OPUS- Projects coordinates.
I Read The Article, They Knew The Problem...
But made no effort to correct it.
They may not have known how simple the correction was.
Longer files could not make up for the lack of proper data. It did improver the solution but not to the extent possible.
Paul in PA
I Read The Article, They Knew The Problem...
It was a software setting, likely discovered after the fact. The longer data was not subject to the software setting, so it did have the P2 data. Therefore they were able to simply divide up the 48 hour files into 20 minute files and get full fledged OPUS-RS solutions.
I included that in the quote above.
I Read The Article, They Knew The Problem...
Shawn,
Thank you for your diplomatic and informative answer. I have been following this board for years, but rarely post. Unlike Kent, who loves to engage in "discussions", but clearly is very well qualified and prepared for such "discussions", other posters simply are intent on discrediting the "facts", even when supplied by the NGS Chief Geodesist of 10 years. You obviously closely read the paper and understood that they took data collected for another purpose and used it to analyze and report on the findings.
If Mr. Paul in PA can't appreciate the document for what it is, and value of the information contained therein, well, I guess he is just smarter than the rest of us. Or, unwilling to learn. I go with the latter based on my observations of this forum over the years.
Scott
I Read The Article, They Knew The Problem...
After that post, I feel obligated to no longer be anonymous on this forum. I have been a Professional Land Surveyor in California since January, 1987. I have strived to learn something new every day of my very fulfilling career and have done pretty well at doing so. I currently serve as the Vice Chair of the Executive Committee for the California Spatial Reference Center. I am the Chair of the NGS endorsed Western Region Height Modernization Consortium, representing 11 western U.S. states. I support about 90 field crews as a subject matter expert in geodetic control and GPS surveys in my day job. I have worked in the field of geodesy for many years and been the primary project surveyor on some of the largest height modernization projects in the country. I have worked with some very smart people and have learned a tremendous amount as a result, yet I have very much more to learn. People like Dave Doyle, Richard Snay, and Dru Smith intimidate me, but I take advantage of every opportunity I get to learn from them.
I have learned a lot by being a member of this forum and appreciate much of the great information shared here by the active members. I rarely post, but when I do, I try to contribute something meaningful that hasn't been posted, like the document I shared today. I was aware of this document because I work closely with the NGS staff on a frequent basis. I do so because I want to learn and become a better surveyor and eventually be able to contribute to this noble profession in some meaningful way. And, because I am fortunate to be in a position to do so.
However, condescending attitudes are something I have never taken well to. Not as a recipient nor a deliverer. When a person's first reaction is to critique something that some obviously very smart and qualified people have taken the time and effort to share with our profession, well, I just have to presume that person has no interest in learning. Or, they have such a high opinion of themselves that they believe they have nothing to learn from others. Either way, it is their problem to deal with. As a mentor, when I sense that type of attitude in a potential understudy, I am much less willing to invest my time and share my experiences and knowledge.
I suppose I have said enough to establish who I am and where I stand on this. Please just don't ever engage me in a duel with Kent. He intimidates me too!! By the way Kent, David Fa german says "hello". Oh, and I was born in Alpine, Texas, so go easy on me if we ever do lock horns.
Scott P. Martin
California PLS 5684
I Read The Article, They Knew The Problem...
Good to meet you Scott. I'm a big fan of geodesy. I'd like to believe that with an additional lifetime, I would make mastering geodesy one of my pursuits, but as it is I think I will have to settle for a deep novice appreciation.
I've seen your posts before and can affirm that you do consistentlyrics offer valuable information with your posts.
Shawn Billings
RPLS 5688
I Read The Article, They Knew The Problem...
Shawn,
Very nice to meet you as well. You are clearly someone who is willing to expose himself to critique via posting here, for the betterment of of our profession and your own knowledge. I highly respect that. I learn way more from this forum than I will ever contribute, but I will make an effort to get more engaged. Although I also have much experience with boundary determination, I prefer to observe and ingest, rather than contribute. I know Dave Karoly and he is truly a student of real property law as it relates to our profession, especially in California. I feel like we should all get Continuing Education Credits for the time we spend here.
Keep doing what you are doing and remain a student of geodesy and all things important to our profession. What we do is important and it matters. In California, things are constantly on the move, whether tectonic plates, subsidence, earthquakes, or even volcanic activity, our geodetic framework is fluid and dynamic. Fortunately, we have a body of knowledge comprised of amazing professionals and scientists to help us deal with our "special needs." I reside on the fringes of those highly intellectual individuals, grateful for the opportunity to work with, learn from, and hopefully contribute to the great work they are doing. There are many others, in other states, doing the same, like Gavin Schrock.
My father's neighbor, Syd, once told him a funny story. They had a neighbor (rural area) who was always poking his nose in, telling folks how to do something, or what they were doing wrong. That guy's name was Earl. One day, Syd was talking to my dad and Earl's name came up. Syd said "You know Jerry, between me and Earl, we know everything in the world." My dad was puzzled and asked "How is that, Syd?". Syd said "Well, Earl knows everything in the world, except that he is an idiot, and I know that, so between us, we know everything."
We all have an "Earl" in our life.
Scott
Thanks, We us WDS network, but I've been look for NTRIP software to use with an old Trimble 5700 as a science project.
:good:
