Hapon N. Ya. Methods and Models of Filament Defectoscopy for 3D Printed Products. – Qualifying scientific work on manuscript rights. Dissertation for obtaining the scientific degree of doctor of Philosophy in specialty 171 "Electronics". - Kharkiv National University of Radio Electronics, Kharkiv, 2024.
Annotation content. The dissertation is devoted to the improvement of methods and models of filament defect detection for 3D printing The purpose of the research is to improve the methods and models of defect detection of the 3D printing filament, to create a technical tool, to increase the accuracy and reliability of the results obtained through the use of methods.
The purpose of the study is improvement of methods and models of defect detection of 3D printing filament and improvement of consumer characteristics of the filament.
The practical significance of the research results is that:
The author of the dissertation developed a methodological apparatus and applied foundations of defectoscopy of filament of 3D printed products, principles of construction of hardware implementation and methods for determining the transmission and reflection coefficients of a filament sample for 3D printing with defects, and also developed a methodology for performing measurements.
In "ASANAFLEX" LLC, the results of the work are used in the economic contract topic "Development of models and methods of filament defect detection for 3D printing", topic 21-04, state registration number 0121U110173 (implementation act dated 06.20.2021).
At the DOED department of KhNURE, the results of the work are implemented in the educational process, where they are used during lectures, practical and laboratory work.
The scientific novelty of the obtained results is that:
– the Nicholson-Ross-Weir method has been improved, which, unlike the classical method, takes into account defects in the filament of 3D printed products, which has allowed to increase accuracy and reliability;
– the model has been improved by taking into account the defect in the model in the form of an signal flow graph, in the style of the classical Nicholson-Ross method, which differs in that previously the defect was not taken into account, and the dielectric was considered idealized without a defect, but according to the proposed model, the defect is also an signal flow graph presented as a section of the graph and is analogous to the model of a dielectric in a waveguide on a reduced scale, thanks to the reduction of the graph by topological, algebraic and matrix methods, analytical expressions were obtained that connect the elements of the scattering matrix with the electrophysical parameters of the filament;
– the thermal quadrupole method has been further developed, which, unlike the known one, provides an additional equation in the system of equations, which allows to equalize the number of unknowns and equations and obtain an unambiguous definition of the parameters of defects;
– the model of a multilayer filament for determining the depth of occurrence and thickness of a defect has been improved, which differs in the use of the objective function of the residuals, equating the derivative of which to zero allows to determine an additional equation between the sought variables, which allows to unambiguously determine the relationship between the depth of occurrence, the opening of the defect and to determine the material of the defect.
