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GNSS workflows involve coordinating the following three columns in the most efficient manner for each survey project.
•Coordinate Reference System
•Survey Type
•GNSS Type
The table below lays out some of the relationships TPC helps you coordinate, so you can accomplish any workflow.
Coordinate Reference System
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Survey Type
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GNSS Type
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Survey CRS = GNSS CRS
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Data collection only
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RTK via NTRIP
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Use GNSS's CRS
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Stakeout
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RTK via Base / Rover / Radios
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Use Survey's CRS
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Corner search
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PPK
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A Simple Workflow
Data collection only for a survey that uses the same CRS as the GNSS.
•You are asked to collect the monuments of record for a city project with 1 cm accuracy
•The site has cell coverage and you are subscribed to an NTRIP network that provides NAD83(2011) positions
•You can expect 1 cm accuracy at this location in your NTRIP network (distance to mount point, L1/L2, etc.)
•All points are to be submitted as a shape file using their geodetic positions (latitude, longitude)
In the Office
1.Create a survey in NAD83(2011) in TPC and do all records research in that CRS
2.Export monument positions to GNSS
In the Field
1.In the field, collect data, do corner searches, etc. using RTK NTRIP corrections
Back in the Office
1.Export to TPC to review and qualify data (RMS, PDOP)
2.Export from TPC to ESRI Shape as geodetic positions
3.Review exported shapes in ESRI
A More Complex Workflow
You want to use GNSS to stakeout a foundation for an existing survey that is NOT on the GNSS CRS
•You did the boundary/site/topo survey with a total station using 5000/5000 some time ago
•You now have a CAD file of the plans at 0/0 and ground coordinates or a PDF of the plans
•You choose to update your survey to the GNSS's CRS
•The site has cell coverage and you are subscribed to an NTRIP network that provides NAD83(2011) positions
•You can expect 1 cm accuracy at this location in your NTRIP network (distance to mount point, L1/L2, etc.)
In the Office
1.Calibrate the CAD file to your survey and insert it as an XRef into your boundary drawing or enter the dimensions from the PDF of the plans
2.Review and verify lot line offsets, easements, etc. Correct if needed.
In the field
1.Get GNSS positions on 2 or more survey control points (3 that encompass the project is adequate) using RTK NTRIP corrections
2.Export those positions to TPC running on a laptop accessing your hotspot used for RTK NTRIP, and calibrate the entire survey to the GNSS CRS
3.Export calibrated control and stakeout points to GNSS
4.Due GNSS corner search for at least 2 of the survey's calibrated control points to verify your calibration
5.Stakeout using RTK NTRIP corrections
6.Measure the staked points using RTK NTRIP corrections
Back in the Office
1.Imported the staked points and do a stakeout report to check residuals
Related Topics
Using GPS/GNSS
Editions
Premium, Professional
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