Familiar surveying workflows onboard Leica ScanStation P-Series 3D laser scanners
Combining high-speed and high-quality scanning with total station methods to calculate station coordinates in the field
Leica ScanStation P-Series survey-grade 3D laser scanners boast a variety of onboard surveying workflows which are typically well-known by surveyors from the use of their total stations. These workflows, Quick Orientation, Set Azimuth, Known Backsight, Four or Six Parameters Resection, Auto Resection and Traversing, offer the setup and orientation of the instrument by known control points, or by calculating the coordinates of unknown stations by aiming at known target control points.
By using the guided, onboard surveying workflows on the ScanStation P-Series, users are able to achieve geo-referenced data directly in the field via the laser scanner onboard user interface. For example, a Resection or Auto Resection option with four or six parameters allows for the calculation of coordinates and orientation of an unknown station, simply by measuring known targets around the setup. Such a procedure is daily business for surveyors when using modern total stations.
How does the Resection application work?
With the Resection workflow, users can opt for a full six parameters transformation which means three translations along the X,Y and Z axes and three rotations around the same axes. This requires a set of at least three known targets to be acquired. In addition, the four parameters resection allows for the same three translations but for a rotation around the Z axis only. This results in a minimum of two required known targets only, but implies a high accuracy tilt compensation for the levelling of the laser scanner.
As target identification can be easily mixed up and can create a lot of confusion and additional work, the Auto Resection option offers the acquisition of the targets without any target ID input - the geometry of the target configuration around the laser scanner is used to match the correct targets.
Post-processing the data
Surveyors often have to deliver data that is registered to a job coordinate system (e.g. a construction grid). This data is required onsite without delays by office post-processing.
ScanStation P-Series onboard surveying applications assist in getting registered, geo-referenced point clouds quickly by a ‘total station like’ procedure.
Specifically for Resection methods mentioned earlier, this means that station coordinates with standard deviations and target coordinates with their residuals can be displayed as values and graphical plots immediately in the field. This helps to get geo-refenced scans directly in the field. Registration errors, which are typically found during office post-processing, can be detected and avoided immediately during the scan acquisition process.
What’s unique about the onboard surveying applications?
ScanStation P-Series instruments are the only laser scanners in the market which include this complete set of surveying workflows. Such workflows are offered based on some unrivalled and fundamental features of the P-Series laser scanners. A highly accurate dual-axis compensator as used in Leica Geosystems high-end total stations guarantees for levelled scan data. ScanStation P-Series instruments are the only laser scanners with active target acquisition and coordinate calculation onboard, even with a two-face target scan option. For this, black and white targets are used in the same way as reflector prisms for total stations. If needed, a laser plummet allows for a precise instrument setup over a marked point, while input options for atmospheric and geometric corrections define the scale factor for correct distance measurements.
How to get access to the onboard surveying applications?
All surveying workflows are pre-installed applications on all ScanStation P-Series laser scanners and are free of charge, no additional licence or cost is required to get started. Any measurement professional that knows how to work with surveying workflows on a total station, intuitively knows how to use them on a 3D laser scanner.
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Product Manager, Terrestrial Laser Scanning
Reality Capture Division