Fitting together pieces of a puzzle
Many factors turned this surveying project into a real challenge. However, the swinging movement that occurred when walking on the roof trusses high above the ground made collecting precise data difficult. These measurements were also absolutely necessary to properly connect the roof area in the network. In order to keep the movement to a minimum, the Leica TS15 was positioned on the roof truss and the data was collected by remote control.
Detailed aerial images were collected using a UAV from areas where the scanners could not be positioned, such as for external roof or tower areas. This resulted in approximately 3,200 facade photos used for corrections and processing. Around 500 distinct points from the scanned point clouds were determined as the foundation points to link the images together.
With the help of Leica Geosystems products, the Pilhatsch surveyors were able to scan the Bonner Münster in the course of 13 days. In order not to disturb visitors at the church, public areas were scanned during four night sessions. Later, light exposure adjustments, or high definition range (HDR), optimised the panorama images. During the project, some 750 scanner standpoint setups were carried out. This resulted in a set of 15 billion data points, which were mapped onto the geodetic reference network to create the final resulting 3D pointcloud.
Handling such large amounts of data was easily possible thanks to Leica Cyclone. This software enabled the billions of points in the original scans to be seamlessly stitched together, regardless how large the volume of data was.
The point clouds provided the basis for further evaluation in CAD software using Leica CloudWorx software. Thanks to this powerful tool, creating levels and sections without any technical limitations whatsoever was easily possible.
Highly efficient workflows helped save Pilhatsch surveyors a tremendous amount of time on this complex project. By using Leica Geosystems solutions, designed to seamlessly combine and integrate workflows, made the processing of such enormous volumes of data much easier. And for the Pilhatsch surveyors, this meant that the results of this big and technically exciting project could be delivered reliably on time.
Chapter 1: Part 1
Chapter 2: Part 2