Laser scanning on the go
Chapter 3: Mobility in a difficult space
Mobility in a difficult space
There were many challenges working in a railway environment whilst trying to capture reality data during this project. From low-hanging electrical lines to constricted spaces around train cars, classical surveying methods can be extremely limited in this environment. Whilst working on the rail project, Prisma Van Steenis had to take the measurements whilst the yard was in use, and, therefore, there were real risks of collisions and a high risk to personal health and safety. By law, the risk area (the railway track) is not an accessible area for surveyors and is normally prohibited for inspections. Prisma van Steenis needed a safe, quick and accurate solution to collect the point clouds and 360-degree pictures needed for this scanning project. The survey needed to be collected quickly to reduce cost and lead time.
The deployment of the Pegasus:Backpack provided numerous advantages over traditional methods for the Prisma Group. The surveyors were a lot safer on the tracks and ran much less risk to their health because they did not have to enter the risk area. In addition to this, the surveyors did not have to perform any measurements during nightfall, which is a hazard in itself with limited visibility causing many hazards. The Pegasus:Backpack was the perfect solution. Distances could be measured without entering dangerous areas with maximum effect. With one measurement from the Pegasus:Backpack, the surveyor was provided with the correct, current and complete information on the same day. The quality of the measurements from the Pegasus:Backpack is highly accurate and best in class.
The results of the project were compared with traditional terrestrial surveying (that took several days to complete) and the results from the Pegasus:Backpack were very impressive. The differences between the backpack's scan and the digital measurements are about 3 centimetres on an absolute level, and the relative results are even better (mm level). The captured 3D data can be used to build a reliable design of a new rail track layout. The newer technology also allowed the measurement professionals to conduct the entire survey in three hours, that would normally take five days. There was also a cost saving of nearly 50 percent for the contractor. The advantage of scanning is that you capture the entire situation, so any forgotten detail can be obtained from the point cloud at a later date if necessary.
“Using wearable reality capture enabled us to realise many benefits over traditional surveying techniques,” said Prisma Director Klaas de Weerd. “With Leica Pegasus:Backpack, every spot in the rail yard was reachable. We also did not have to implement extra safety measures since there was no need for us to enter high-risks areas: we could simply capture the data from a safe distance. Finally, we saw great time savings due to error-free data acquisition in a baseline survey that will allow us to accurately monitor any changes to the design in the future.”