High-accuracy digital rail crossing inspection
The Dutch railway network has more than seven thousand track switches and crossings. These components are prone to wear and frequently require labour-intensive repairs. Within the XCross research consortium, TU Delft is working with other partners to optimise the inspection and maintenance process. The project recently received funding from the European Union.
Rail crossings are the weak links in the system and suffer a lot, explains Valeri Markine. He is project leader of XCross and Associate Professor of Railway Engineering at TU Delft. “The rails are interrupted at a crossing. Passenger and heavy freight trains experience a noticeable impact, a ‘jump’ so to speak, when passing crossings. This puts significant stress on the rails causing them to wear out quickly.”
Manual inspection of the track.
Pilot test with hand-held 3D scanner.
From manual inspections to high-tech solutions
Currently, the damage to rail crossings is assessed manually by professionals who look for blemishes with the bare eye. They fix the worn junctions by welding and grinding- an intricate, manual process requiring precision. The XCross team aims to enhance this process using hand-held 3D scanning technology. The scanners can detect surface irregularities with high accuracy and feed real-time data into computer models, providing immediate insights. This technology could assist welding professionals by offering virtual reality guidance or even customised printed moulds for repairs.
Enhancing maintenance planning
By comparing scanned data with the original rail geometry, computer models can not only detect deviations but also generate optimised repair solutions tailored to specific conditions. It becomes immediately visible on the screen where material needs to be added or removed. Besides valuable information for welders on-site, Markine thinks this could also provide inspectors information that will allow maintenance work to be planned more effectively.
Versatile
Another key advantage of the computer models, the digital twin, is that they can simulate various railway conditions. Across Europe, different train types, rail profiles and wheel configurations are used. This leads to varying track-vehicle interactions. Since railway maintenance and repairs require millimetre-level precision, incorporating these variations into digital models is crucial for effective repairs.
Extending the lifespan of rail infrastructure
Markine is pleased that industry leaders such as ProRail and RET are actively involved in the innovations within the XCross project. The ultimate goal is to spot wear and tear at an early stage, enabling timely or even preventive repairs. This approach will help to extend the lifespan of the railway infrastructure.
The Next Generation of Railway Crossing Asset Management Technology project (XCross) is funded by Europe's Rail Joint Undertaking, the European partnership for railway research and innovation. Within this project, ten partners from seven different countries are working together. Besides TU Delft, these include ProRail, Rotterdam Electric Tram (RET), International Union of Railways (UIC), Dresden University of Technology (TU Dresden) and University of Leeds. Go to project website for more information.
Photo credits: TU Delft