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PROBLEMS WITH POSITION OF GPS POINTS.

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(@bryce)
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seemed like Mark was troubleshooting this issue just fine

 
Posted : 04/07/2017 10:49 pm
(@eduardo_01)
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Which program do you use for the post-process?

 
Posted : 05/07/2017 8:29 am
(@eduardo_01)
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Nate The Surveyor, post: 435287, member: 291 wrote: Eduardo, I do not know the answers to making LOCUS PROCESSOR work today.....
However, I do know that the LOCUS units were made by a company named ASHTECH. Ashtech, was named that, because Javad Ashajee, was the guy that assembled the team, and made them. (Some were sold, with SOKKIA name, but it was the SAME receiver. )
Somebody somewhere, knows what to do.

And, on that note, I suggest you post over on the Javad Forum.
https://support.javad.com/index.php

I can't help you... but those guys are smarter than I am. (Many folks on this forum are smarter than I am!) I suspect you may find a few leftovers, who were involved in the creation of Ashtech Solutions. And, that's as close to the horses mouth as I know.

I still have 2 Locus units....

Nate

Which program do you use for the post-process?

 
Posted : 05/07/2017 12:04 pm
(@base9geodesy)
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The ITRF which is a product of the International Earth Rotation and Reference System Service does not have its own ellipsoid. Coordinate values are originally published as X,Y,Z Earth-Centered Earth- Fixed. The user applies whatever ellipsoid they want which should be GRS80 which is the international standard. The difference between NAD 83 and ITRF coordinates in the conterminous U.S. is approximately 1.5 m in 3-D.

 
Posted : 05/07/2017 12:46 pm
(@eduardo_01)
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base9geodesy, post: 435386, member: 7189 wrote: The ITRF which is a product of the International Earth Rotation and Reference System Service does not have its own ellipsoid. Coordinate values are originally published as X,Y,Z Earth-Centered Earth- Fixed. The user applies whatever ellipsoid they want which should be GRS80 which is the international standard. The difference between NAD 83 and ITRF coordinates in the conterminous U.S. is approximately 1.5 m in 3-D.

And in case both programs use the same geoid model?

 
Posted : 05/07/2017 7:14 pm
(@billvhill)
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Are you post processing holding the same point and the same coordinates

 
Posted : 05/07/2017 7:30 pm
(@eduardo_01)
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billvhill, post: 435461, member: 8398 wrote: Are you post processing holding the same point and the same coordinates

Yes.

 
Posted : 05/07/2017 8:03 pm
(@eduardo_01)
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billvhill, post: 435461, member: 8398 wrote: Are you post processing holding the same point and the same coordinates

They are the same points, but they throw me different coordinates.

 
Posted : 05/07/2017 9:21 pm
(@a-harris)
Posts: 8761
 

Locally, 2meters is about the separation between self obtained WGS84 positions as derived from TxDot non OPUS control points and those obtained by running the data thru OPUS for the real thing.

 
Posted : 06/07/2017 3:24 am
(@eduardo_01)
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A Harris, post: 435490, member: 81 wrote: Locally, 2meters is about the separation between self obtained WGS84 positions as derived from TxDot non OPUS control points and those obtained by running the data thru OPUS for the real thing.

Is it a post-process result ?.

 
Posted : 07/07/2017 7:41 am
(@a-harris)
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It is a difference between OPUS results and stand alone results.

 
Posted : 07/07/2017 12:57 pm
(@mark-mayer)
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A Harris, post: 435846, member: 81 wrote: ....stand alone results.

i don't understand what you mean by "stand alone results". Do you mean autonomous positioning? OR perhaps TxDOT data sheets on control monuments?

 
Posted : 07/07/2017 1:27 pm
(@a-harris)
Posts: 8761
 

There are many TxDot GPS stations that have not been confirmed by OPUS and using them can result in what you call autonomous positioning, something I relate to RTK.
For static, I usually say stand alone because there is no actual known control point used to confirm position.

 
Posted : 07/07/2017 2:20 pm
(@nate-the-surveyor)
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I have a suspicious feeling...
He's got an autonomous position.
I NEVER was able to EXPLAIN to my dad, why this did not work.....

N

 
Posted : 07/07/2017 2:40 pm
(@bk9196)
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With what he's explaining it really looks like separate static observations processed through GNSS Soulutions, One using using us survey feet and the other international feet, made the same mistake 10 years ago, problem echos as very similar.

 
Posted : 07/07/2017 6:38 pm
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