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Primary Control Set Up

Primary Control Set Up

Primary Control Set Up


I am in the process of setting up the site primary control and would like advise on how to ensure its accuracy.

I have installed 11 points around the site using a Leica GPS GSO6 instrument.
I shot each point 5 times and took the average reading.

I have now traversed the between the points using a Leica TS16 EDM to clarify the bearings and distances between each point.

Now I would like to use the traversed survey and set it as the primary control references back to the GPS survey coordinates.

How do I do this?

Bear in mind I am not a land surveyor and do not have the maths skills that some of you may have.

Have have plotted both surveys in CAD so what thinking a simple CAD technique may do it?

Thanks in advance.


RE: Primary Control Set Up

When I had this done I hired a licensed surveyor, surveyor as that was needed to ensure the data would be valid for use in other engineering projects stamped drawings.

Reconciling GNSS / GPS observations can be a bit painful, particularly if you have not taken care to understand the uncertainties in the various components of your survey.

For GNSS observations, longer is better.

OPUS and most other services that output position will provide a much smaller uncertainty than the basic output of a GNSS receiver - unless your Leica GPS GSO6 is set up to perform real time post processing (usually a subscription service).

All of the software used by surveyors for this purpose uses least squares to resolve uncertainties in GPS observations, and closure inconsistencies in conventional surveys. I do not recommend trying to do least squares by hand, it is a tedious but powerful technique. Principle of Least Squares Applied to Surveying

If you are attempting to combine GPS data at each point, with a conventional survey, using just a CAD program, I suggest you plot your GPS points, and your Conventional survey points separately, xref them together, then move the conventional survey around until you get a reasonable alignment between the GNSS and the conventional survey.

If the result is not fit to task, you should discuss the matter with a surveyor.

RE: Primary Control Set Up

For this you have to search in google.

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