The rigid body transformation between the coordinate systems of the pattern planes is estimated in the optimization routine. A roof-shaped calibration target with two individual point pattern planes is used to calibrate the sensor. To ensure sufficient contrast, projector light with a central wavelength of 525nm and matching optical camera band-pass filters are used. Homologous points are detected by means of a sorting algorithm or, alternatively by rectification and horizontal 1D line search. To solve the stereo correspondence problem, an entocentric projector is used to project a fringe pattern sequence onto the measuring object. The suitability of the affine camera model for measurements through plane-parallel glasses is demonstrated by theoretical considerations. This ensures a uniform influence of the refractive interfaces onto the path of the camera rays. The designed sensor concept is based on telecentric lenses and plane-parallel inspection glasses with high planarity. For this purpose the measuring object is placed in a specially developed vacuum measuring cell, and the measurements are realized from outside the cell through optical inspection glasses. To investigate the effect of the heat-induced inhomogeneous refractive index field on the reconstructed object surface, measurements are conducted and compared both at ambient pressure (full light deflection effect), and at pressure levels of approximately 90mbar (rough vacuum). Especially, the system is meant to allow a surface reconstruction of high-temperature reference measuring objects, such as a repetitively heatable ceramic cylinder in order to validate alternative light-deflection compensation concepts in forthcoming work. The objective of this thesis is the development and calibration of a fringe projection sensor based on an affine stereo camera pair to perform geometry measurements on high temperature components with temperatures up to 1000 ☌ to generate a first basic understanding of the light deflection effect. However, measurements of high-temperature components offer the potential of an early error detection and a monitoring of the manufacturing process. Radiation, as well as the inhomogeneous refractive index field in the vicinity of the measuring object. Methods is challenging due to the workpieces’ self-emission of electromagnetic The geometrical characterization of forge-hot workpieces based on optical triangulation
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