A New Approach for Inspection of Selected Geometric Parameters of a Railway Track Using Image-Based Point Clouds

作者：Gabara Grzegorz^*; Sawicki Piotr^*

来源：Sensors (Switzerland), 2018, 18(3): 791.

DOI：10.3390/s18030791

• DSLR camera
• dense matching
• point clouds
• 3D object reconstruction
• track geometry

The paper presents the results of testing a proposed image-based point clouds measuring method for geometric parameters determination of a railway track. The study was performed based on a configuration of digital images and reference control network. A DSLR (digital SingleLens- Reflex) Nikon D5100 camera was used to acquire six digital images of the tested section of railway tracks. The dense point clouds and the 3D mesh model were generated with the use of two software systems, Reality Capture and Photo Scan, which have implemented different matching and 3D object reconstruction techniques: Multi-View Stereo and Semi-Global Matching, respectively. The study found that both applications could generate appropriate 3D models. Final meshes of 3D models were filtered with the Mesh Lab software. The Cloud Compare application was used to determine the track gauge and cant for defined cross-sections, and the results obtained from point clouds by dense image matching techniques were compared with results of direct geodetic measurements. The obtained RMS difference in the horizontal (gauge) and vertical (cant) plane was RMS Delta < 0.45 mm. The achieved accuracy meets the accuracy condition of measurements and inspection of the rail tracks (error m < 1 mm), specified in the Polish branch railway instruction Id-14 (D-75) and the European technical norm EN 13848-4: 2011.

• 出版日期2018-3