Control of mobile equipment for the processing of marine shaft lines

Abstract The purpose of the research is to develop solutions for mobile equipment control in the processing of marine shaft lines; to solve the issues of geometric accuracy of processing; to create a corrective program to address the issues of accuracy of the geometric parameters processing; to give reasons for the application of linear electrohydraulic step drive (LEHSD) in mobile equipment control. The analysis of schemes and mathematical dependencies for calculating the trajectory of the tool movement of a mobile machine when processing shaft lines is carried out; the choice of the optimal zone for finishing the shaft line, taking into account the beats. The object of the study is a ship shaft line. The paper presents an original scheme of rotation of the shaft line section, as well as schemes for changing the position of the shaft line during processing; justifies the possibility of using a linear electrohydraulic step drive (LEHSD) with a corrective program for processing taking into account automatic measurements and a specified error.

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Checking the Geometric Accuracy of a Machine Tool for Selected Geometric Parameters

Acta Polytechnica ◽

10.14311/1594 ◽

2012 ◽

Vol 52 (4) ◽

Author(s):

Adam Janásek ◽

Robert Čep ◽

Josef Brychta

Keyword(s):

Machine Tool ◽

Geometric Parameters ◽

Milling Machine ◽

Control Parameters ◽

Geometric Accuracy

This paper deals with the control parameters for selected geometric accuracy measurements for a machine tool. The parameters were needed after a refurbished milling machine was purchased. After setting up the machine, it was necessary to check the geometric accuracy that can be used for precise milling. The whole check was performed in accordance with ISO 10791. Only selected parameters of geometric accuracy were inspected, and they were later compared with the prescribed values. On the basis of a comparison of these values we were able to determine whether the machine tool can be used for accurate machining.

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Method of controlling geometric accuracy for ship shafts

MORSKIE INTELLEKTUAL`NYE TEHNOLOGII ◽

10.37220/mit.2020.49.3.011 ◽

2020 ◽

Author(s):

А.В. Гринек ◽

С.П. Тимофеев ◽

С.И. Кондратьев ◽

А.В. Хуртасенко

Keyword(s):

Control Method ◽

Three Dimensional ◽

Geometric Parameters ◽

Cylindrical Shape ◽

Geometric Accuracy ◽

Original Design ◽

Cylindrical Parts ◽

Axis Position ◽

Measuring Machine ◽

Dimensional Simulation

В статье представлен способ контроля параметров геометрической точности элементов гребных валов: радиального биения поперечного сечения, отклонения реального профиля вала от цилиндрической формы. Целью работы являлось научное обоснование способа контроля и реализация методики контроля. Разработан алгоритм и схема измерений погрешности формы и положения оси составных валов гребного валопровода на основе существующих авторских решений по контролю точности формы крупногабаритных цилиндрических изделий, в том числе с нестационарной осью вращения. Разработана оригинальная конструкция устройства для контроля геометрических параметров и изготовлена экспериментальная установка и лабораторный образец на базе датчиков отечественного производителя. Алгоритм и методика протестированы с помощью имитационной трехмерной модели. На основе предложенной схемы может быть построено мобильное измерительное оборудование с ручным или автоматизированным измерением - контрольно-измерительная машина. Программно-аппаратная реализация такого оборудования также может основываться на разработанных алгоритмах определения геометрических параметров. The article presents a method for controlling the parameters of geometric accuracy of elements of propeller shafts. The purpose of the work was scientific justification of the control method and methodology implementation. These parameters include the cross section radial runout and the real shaft profile deviations from the cylindrical shape. The author's solutions in the field of controlling the accuracy of the large-sized cylindrical parts shape are obtained. An algorithm and a scheme for measuring the error in the shape and the shaft elements axis position are developed. The presented engineering solutions are applicable to shafts with a non-stationary axis of rotation. The original design of the device for monitoring geometric parameters was developed and an experimental installation and laboratory sample were made based on domestic manufacturer sensors. The algorithm and methodology were tested using a three-dimensional simulation model. On the basis of the proposed circuitry, a mobile measuring equipment with manual or automated measurement can be built - a control and measuring machine. Software and hardware implementation of such equipment can also be based on the developed algorithms for determining geometric parameters.

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Lectin-Induced RBC Agglutination: Chemical vs. Cryofixation

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s1431927600002920 ◽

1980 ◽

Vol 38 ◽

pp. 664-665

Author(s):

Dean A. Handley ◽

Lanping A. Sung ◽

Shu Chien

Keyword(s):

Lectin Binding ◽

Freeze Substitution ◽

Electrostatic Charge ◽

Geometric Parameters ◽

Comparative Approach ◽

Chemical Fixation ◽

Cell Surfaces ◽

Minimal Cell ◽

Membrane Stiffness ◽

Cell Contour

RBC agglutination by lectins represents an interactive balance between the attractive (bridging) force due to lectin binding on cell surfaces and disaggregating forces, such as membrane stiffness and electrostatic charge repulsion (1). During agglutination, critical geometric parameters of cell contour and intercellular distance reflect the magnitude of these interactive forces and the size of the bridging macromolecule (2). Valid ultrastructural measurements of these geometric parameters from agglutinated RBC's require preservation with minimal cell distortion. As chemical fixation may adversely influence RBC geometric properties (3), we used chemical fixation and cryofixation (rapid freezing followed by freeze-substitution) as a comparative approach to examine these parameters from RBC agglutinated with Ulex I lectin.

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Evaluation of the accuracy of reconstruction of the electrophysical and geometric parameters of multilayer dielectric coatings by the multi-frequency radio wave method of a slow surface electromagnetic waves

Izmeritel`naya Tekhnika ◽

10.32446/0368-1025it.2020-8-51-58 ◽

2020 ◽

pp. 51-58

Author(s):

Aleksandr I. Kazmin ◽

Pavel A. Fedjunin

Keyword(s):

Radio Wave ◽

Noise Level ◽

Electromagnetic Waves ◽

Dielectric Materials ◽

Geometric Parameters ◽

Experimental Investigations ◽

Wave Method ◽

Dielectric Coatings ◽

Surface Electromagnetic Waves ◽

Multilayer Dielectric

One of the most important diagnostic problems multilayer dielectric materials and coatings is the development of methods for quantitative interpretation of the checkout results their electrophysical and geometric parameters. The results of a study of the potential informativeness of the multi-frequency radio wave method of surface electromagnetic waves during reconstruction of the electrophysical and geometric parameters of multilayer dielectric coatings are presented. The simulation model is presented that makes it possible to evaluate of the accuracy of reconstruction of the electrophysical and geometric parameters of multilayer dielectric coatings. The model takes into account the values of the electrophysical and geometric parameters of the coating, the noise level in the measurement data and the measurement bandwidth. The results of simulation and experimental investigations of reconstruction of the structure of relative permittivitties and thicknesses of single-layer and double-layer dielectric coatings with different thicknesses, with different values of the standard deviation (RMS) of the noise level in the measured attenuation coefficients of the surface slow electromagnetic wave are presented. Coatings based on the following materials were investigated: polymethyl methacrylate, F-4D PTFE, RO3010. The accuracy of reconstruction of the electrophysical parameters of the layers decreases with an increase in the number of evaluated parameters and an increase in the noise level. The accuracy of the estimates of the electrophysical parameters of the layers also decreases with a decrease in their relative permittivity and thickness. The results of experimental studies confirm the adequacy of the developed simulation model. The presented model allows for a specific measuring complex that implements the multi-frequency radio wave method of surface electromagnetic waves, to quantify the potential possibilities for the accuracy of reconstruction of the electrophysical and geometric parameters of multilayer dielectric materials and coatings. Experimental investigations and simulation results of a multilayer dielectric coating demonstrated the theoretical capabilities gained relative error permittivity and thickness of the individual layers with relative error not greater than 10 %, with a measurement bandwidth of 1 GHz and RMS of noise level 0,003–0,004.

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