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The videogrammetry method is an improvement of a traditional photogrammetry method realized with the help of modern means of videoengineering, digital registration and image processing. The goal of the method is to restore the three- dimensional coordinates of a required point of an object under test on base of two coordinates of center of the point's image at the registration plane. One of the ways to resolve the arising uncertainty of restoration is to use of a structured illuminating beam of light rays; the known geometry of the beam helps to obtain the missing information. The special cases of such a beam are a light sheet and a beam of the parallel or radial light rays. The methods of videogrammetry with a laser light sheet and with a beam of radial light rays are both simultaneously applied in the measuring system to check the geometrical parameters of railway wheels which has been placed in operation on the industrial conveyor at Vyksunsky steel works. The measuring system uses three videogrammetric channels. Two of them are apply the laser light sheet scheme. These channels have identical features and are intended for measurements of geometry of the radial section fragments of the internal and external disk surfaces of the wheel. The channels have a measurement range of 500 X 500 mm. The measurement tolerance of each of the two coordinates do not exceed 0.15 mm. The third channel is constructed under a shadowgraphic scheme on base of a light beam of radial rays and provides the measurements of the wheel rolling surface geometry. This channel has a measurement range of 120 X 180 mm and measurement tolerance of 0.05 mm. The measuring system works in real time with the conveyor. A wheel tolerance check cycle, which takes 45 seconds includes lifting the wheel to the measurement position, rotating the wheel one full revolution with simultaneous measurement of a given number (up to 12) of radial sections, lowering the wheel to the conveyor line, processing and displaying the measurement results.
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