Rail Flatness Measurement Based on Dual Laser Triangulation

Surface metrology is crucial task in automated quality control. The measurement of surface features such as regular and irregular patterns, roughness, waviness, flatness and dimensions is of utmost importance to ensure products are being manufactured according to specifications. This work focuses on flatness measurement in rails, which is a quality parameter affected by roller deformations during rail production. This work proposes a flatness measurement system for rails based on a dual triangulation configuration. Innovative solutions are provided for the most challenging tasks including calibration, registration, calculation of the deviations of the surface from their intended shape, filtering and flatness characterization. Extensive tests on synthetic and real data indicate excellent performance in terms of measurement accuracy, robustness and reliability.