Industrial Automatic Control Systems and Controllers Annotation << Back Measuring Fiber-optic System for Monitoring Rail Lashes of a Railway Track K.A. Izotov, D.A. Loktev, A.A. Loktev The present investigation is devoted to the development of elements of an information-measuring system aimed at measuring the parameters of the stress-strain state of the rail lashes of a jointless track. Measuring modules are attached directly to the side surface of the rail and contain fi ber-optic sensors having a special structure for changing the refractive index along the length of the base part. Equations describing the deformation of the rail lash under the influence of various internal and external forces are compiled, then the theoretical values of the absolute deformations obtained at the base length of the sensor are estimated. The theoretical values of deformations are compared with the values obtained during full-scale measurements, for this purpose, changes in the parameters of light pulses passing through an optical channel with Bragg gratings are measured. The implemented approaches in measurements and modeling are relevant for sections of the railway track that are most susceptible to deformations with a large gradient of values, for example, in front of artificial structures, at turnouts, in places of heaving of the roadbed, etc. Keywords: measurement and diagnostics system of rail lashes, deformation of the rail lash, optical pulse, pulse duration change, signal envelope, optical fiber parameters, chromatic dispersion, frequency chirp. DOI: 10.25791/asu.10.2022.1388 Pp. 08-17.