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The subject of the study is the process of applying optical technologies for non-contact measurements of geometric parameters of a wagon wheelset during operation and repair. The purpose of the study is to study the methods of field testing of technologies for controlling the geometric parameters of car parts using an optical rangefinder, with mutual verification of the results obtained using numerical modeling using three-dimensional digital models of objects and measuring instruments. As a result of the study, experimental and calculated dependences of the optical sensor readings were obtained during the change in the relative position of the measuring object (wheelset) and the rangefinder. Two laser triangulation rangefinders were used for field tests. For numerical simulation, a program was created that allows generating a three-dimensional model of the rolling surface of a wheelset consisting of a set of points belonging to the surface of rotation. The simulation consists in finding the intersection points of a line defined using the coordinates of the point of the radiation source in space and the guiding vector with the model of the skating surface. After the calculations, the result is given in the form of a table with calculated ranges and visualized as projections of a three-dimensional wire model of a wheel and a rangefinder beam. Visualization of the numerical modeling process is important to avoid misinterpretation of the calculation results and to verify compliance with the physical meaning of the numerical data obtained during modeling. Comparison of graphs shows the convergence of the results and sufficient accuracy of numerical models and techniques that can be used in the future to plan full-scale tests of the designed techniques and equipment for dimensional control of railway car parts.

This article contains results of a preliminary study of the parameters of the laser triangulation sensor in the context of its application to control of a technical condition of details of the car. The main aim of the study is the experimental determination of the limits of applicability of the sensor to monitor the real sample detail of the new design freight car on the example of 18-9855 bogie parts. By the experimental methods where established the threshold limits of applicability of the given sensor, its properties and application features for dimensional control. Also where established limit angles of the distance measurement at the maximum setting of the speed sensor, the actual focal point of the transducer. The analysis of the obtained data allowed authors to make an optimal scheme of automated measurement machine of portal type for control of the size and shape of parts of the car. The results of the work is possible to use when designing automated systems and equipment for dimensional inspection of parts during manufacture, repair and maintenance of railroad cars and other vehicles.

The subject of the study is the theoretical and practical aspects of the application of optical technologies for non-contact measurements of geometric parameters of a wagon wheelset during operation and repair. The purpose of the study is to develop methods and technologies for monitoring geometric parameters of car parts using an optical linear scanner, as well as a method for processing the results of field tests of the results of the application of optical control technologies. The article analyzes the problems of application of standardized methods of technical condition monitoring using manual measuring and control tools in the context of the adopted technology of maintenance and operation of freight cars. As a result of the study, a review of the state of the issue of the use of optical control techniques on the railway was carried out, the strengths and weaknesses of various options for the implementation of measurement techniques were identified and a methodology and a computer program for automating the creation of a digital standard of the object under study (the profile of the longitudinal section of the rolling surface of the wheelset) were developed. Using a digital two-dimensional image of the shadow pattern of the wheel profile, the coordinates of the points of the contour line of the section of the volumetric wheel in the area of the rolling surface are calculated. To determine the coordinates of the envelope of the section, a step function is used, as close as possible to the chiaroscuro image of the wheel contour. After image processing, the result is output by the program in the form of a table with the calculated coordinates of the profile section and visualized using the wheel profile synthesized by coordinates in the program window. The accuracy of the technique used depends on the resolution of the image obtained by the linear scanner. The methodology and program can be used in the future for field tests of the designed equipment for dimensional control of car parts.