莫斯科国立技术大学

We consider available approaches to elevation of the volumetric accuracy in the design and operation of coordinate measuring systems. At present, there exist numerous methods aimed at the evaluation and correction of volumetric errors developed for the technological and measuring machines with specific kinematic schemes but there is no universal method suitable for different coordinate measuring systems. To get a unified methodical approach to the evaluation and correction of volumetric errors of the technological and measuring machines with different kinematic schemes, it is proposed to use the concepts of differential geometry. We develop a method intended for the evaluation and correction of the errors of two-dimensional coordinate measuring systems. This method is based on concepts of differential geometry; geometric errors are understood as discrepancies between the coordinates recorded by the reference system of the measuring system (digital coordinates) and the actual coordinates of the same point. Note that the indicated sets of coordinates are connected by a transformation described with the help of a Jacobian matrix. The proposed method includes the determination of elements of the Jacobian matrix according to the results of measuring of the positioning errors, deviations from rectilinearity, angular deviations, and deviations from the mutual perpendicularity of the axes carried out with the help of an XL-80 laser interferometer (Renishaw, UK). In the case of correction of the errors by the developed method, we applied numerical differentiation and integration, as well as a moving-average filter to minimize random noise. The method was experimentally validated by using a computerized universal measuring microscope (UIM-21). We experimentally establish a substantial decrease in the spread of measurement data after correction, which confirms that the geometric error decreases. The application of the developed correction method makes it possible to reduce the time and the costs of adjustment of the coordinate measuring systems and to adapt the computational procedures and the software developed by the authors for the purposes of the current investigation to different configurations of coordinate measuring systems. The results of the performed theoretical and experimental investigations not only guarantee an increase in the accuracy of in-plane measurement of the geometric parameters but also enable us to extend the proposed method for the evaluation and correction of errors to more complicated multicoordinate measuring systems.

This study aims at enhancing the efficiency of high-speed edge cutting of heat-resistant alloys. The enhancement is based on improving the tribotechnical characteristics of wear-resistant coatings by using multicomponent target cathodes made from sintered high-entropy alloys deposited by the magnetron method. Technologies for producing high-entropy target cathodes (with a diameter of 20 and 70 mm) obtained by high-temperature spark plasma sintering with various content of Al, Cr, Hf, Mo, Nb, Ni, Ta, Ti, V, W, and Zr have been developed; control of their parameters, density, grain-size composition, electrical conductivity, hardness, and crack resistance is provided. The morphology of the sintered samples was examined by scanning electron microscopy and non-dispersive analysis. Production equipment for magnetron coating systems in various gas media is manufactured. Tribotechnical tests were carried out using tribometers and during edge cutting of various grades of steels and alloys. The test results were used to determine the most effective compositions of multilayer composite nanostructured high-entropy wear-resistant coatings, in particular, Al20Ti20Zr15V15Cr15Nb15 and Al20Hf10Ni15Ti25W10Zr20, which provide improved cutting performance of EI654 and EI698VD chromium-nickel alloys. Comparative tests of commercially used wear-resistant coatings and coatings made of high-entropy target cathodes: Al20Hf10Ni15Ti25W10Zr20, Al20Ti20Zr15V15Cr15Nb15, Al20Hf15V15Cr15Ti15Ta10W10, Ti15Zr15Cr15Ni10W10V10Nb15Al10, Ti20Hf15Mo15W10V10Nb15Al15, Ti40Zr10Cr10Ni10W10Mo10Nb10, etc., were carried out. Studies in the longitudinal turning of EI-654 and EI‑698VD chromium-nickel alloys confirmed that the efficiency of using high-entropy coatings on a cutting tool increases on average by 20–25

The structure and phase state of Ti-Al-N systems obtained in the form of a coating and a bulk material were comparatively studied. The structure was characterized using x-ray diffraction, energy-dispersive spectroscopy (EDS), and Raman spectroscopy (RS). The use of EDS and RS made it possible to verify the x-ray diffraction data on the phase composition of the samples, which is especially important in the study of multiphase Ti-Al-N coatings, and to identify the features of the coating surface microstructure. The Ti-Al-N coating was obtained by chemical deposition of Ti and Al in an N-2 atmosphere on a Ti substrate with subsequent annealing in vacuum at 700, 800, 900, and 1000 degrees C. The bulk Ti-Al-N sample was obtained by reaction sintering of Ti, Al, and TiN powders in vacuum at 1200 and 1300 degrees C. The Ti2AlN MAX phase appeared in the coating at a lower temperature than in the bulk sample and was characterized by lower thermal stability. The Ti-Al-N coating was characterized by a greater multiphase nature. The phases Ti2AlN, Ti4AlN3, TiN, Ti2N, and AlN were detected in it after annealing in vacuum at 900 degrees C. The MAX-phase structure was destroyed at 1000 degrees C. The main phase in the bulk sample after annealing in vacuum at 1300 degrees C was Ti2AlN with a small admixture of TiN and TiAl. The Ti2AlN MAX phase was destroyed at 1400 degrees C.

This paper presents a visual inspection system for the orientation of micro-assembly components, designed for use in automated manufacturing complexes. The objective of the developed algorithm is to detect microchips placed in waffle packs that deviate from the permissible angular orientation. The proposed method involves image preprocessing based on Gaussian and multicriterial method smoothing, threshold segmentation, and morphological transformations, followed by object contour extraction. For each detected element, the rotation angle relative to the horizontal axis is estimated. Elements exceeding the set angular deviation threshold are registered and visually marked for subsequent positioning by actuators. The developed approach can be integrated into machine vision systems of industrial assembly lines to ensure orientation control and placement quality in micro-assembly processes.

We study magnetic geodesic flows invariant under rotations on the 2-sphere. The dynamical system is given by a generic pair of functions (f,Λ) in one variable. The topology of the Liouville fibration of the given integrable system near its singular orbits and singular fibers is described. The types of these singularities are computed. The topology of the Liouville fibration on regular 3-dimensional isoenergy manifolds is described by computing the Fomenko–Zieschang invariant. All possible bifurcation diagrams of the momentum mappings of such integrable systems are described. It is shown that the bifurcation diagram consists of two curves in the (h,k) -plane. One of these curves is a line segment h=0 , and the other lies in the half-plane h≥0 and can be obtained from the curve (a:-1:k) = (f:Λ:1)^* projectively dual to the curve (f:Λ:1) by the transformation (a:-1:k)↦(a^2/2,k)=(h,k) . DOI 10.1134/S1061920825600084