Mechanics and Advanced Technologies

Neural Networks and Artificial’s Intelligence’s Algorithms in the Tasks of Diagnostics Foreign Bodies in the Wound Channel of Patients

2025-11-26T11:13:22+02:00

The paper considers a device in which information about the presence of a foreign body a fragment in a wound is obtained using a special compact sensor: a mechanical elastic flexible rod, which is placed in a protective soft tube and connected to a sealed chamber, one of the walls of which is a membrane capable of converting the vibrations of the rod into sound waves, which, propagating in the chamber, are recorded by a microphone. Mounted in a convenient housing, the sensor is connected to sound frequency filters (up to 15 kHz) via an amplifying link and allows you to obtain a noise signal, based on which you can detect the contact of the rod with a foreign body during its movement in the patient's wound. The difference in the spectrum patterns suggests that such a device can be used not only to detect foreign bodies, but also to identify them.
The use of neural networks and artificial intelligence algorithms significantly improves the accuracy of foreign body detection, especially for small objects and those whose rheological properties are similar to the patient's tissue. Thus, with the appropriate adjustment of the device, the accuracy of foreign body diagnosis is currently up to 65–95 % for bodies larger than 3.5–5.0 mm; higher accuracy is observed when detecting bodies with pronounced elastic properties.
It has been shown that the use of this device allows obtaining information about the presence of a foreign body (due to the appearance of separate clearly defined signal peaks), while the absence of foreign bodies gives a picture of noise emission distribution close to the Gaussian distribution; about the type of foreign body. The shape of the pattern allows one to assess the type of foreign inclusion (more elastic bodies have more pronounced frequency spikes); to estimate the approximate size of the body: larger bodies are in contact with the probe for a longer time as it moves.

Fabrication and Property Comparison Aluminium TiB2 Composites Manufactured Through Additive Manufacturing and Conventional Manufacturing: a Comparative Review

2025-11-11T11:26:49+02:00

Additive manufacturing is most emerging techniques of fabricating components with desired dimensions to the near net shape. Metal additive manufacturing is the challenging area and lot of research under progress. In the present review paper, an attempt is made to compare the properties of aluminium reinforced TiB₂ metal matrix composites fabricated through conventional manufacturing technique and also LASER assisted additive manufacturing technique. Bulk composite materials casting (stir casting) is followed for conventional method and layer wise material printing is done in additive manufacturing. Upon fabrication, the specimens are checked for particle distribution using SEM images. It is observed from micrographs that, distribution of reinforcing particles i.e. TiB₂ is fair enough in the composite fabricated through additive manufacturing technique. This influences possessing the uniform properties for further testing. The microhardness of the two different specimens are checked and it is found that, composites manufactured though conventional manufacturing showed higher hardness than composites manufactured though additive manufacturing. Higher composite ductility is observed in additive manufactured specimen.

Real-Time GPU-Accelerated Topology Optimization of a Compact Bracket: A Simulation-Only Workflow

2026-01-29T16:04:36+02:00

Background: Topology optimization (TO) is widely adopted for lightweight structural design; however, its integration into early-stage engineering workflows is often constrained by computational expense and long solution times associated with conventional CPU-based solvers. The emergence of GPU-accelerated simulation environments offers the possibility of transforming topology optimization into a more interactive and accessible design tool. Objective: This Technical Note evaluates a practical GPU-accelerated workflow for topology optimization and examines its suitability for conceptual lightweight structural design using commercially available software. Methods: A compact triangular bracket was selected as a representative case study and analysed in ANSYS Discovery Live. A static concentrated load of 100 N was applied at one mounting interface, while the remaining interfaces were constrained using cylindrical supports to represent mechanically consistent boundary conditions. No dynamic or transient loading effects were considered. The optimization problem was formulated as compliance minimization subject to a 50 % global volume constraint. Material behaviour of AlSi10Mg was modelled as linear elastic and isotropic to ensure compatibility with the real-time GPU solver. Mesh sensitivity analysis and supplementary simulation-based validation checks were performed to assess structural consistency within a conceptual design framework. Results: The optimized configuration achieved approximately 50 % reduction in material volume while maintaining stresses and deformations within conservative limits under the prescribed static loading condition. Material redistribution followed principal load paths, and mesh refinement studies indicated stable topology convergence. The GPU-based solver enabled continuous visualization of stress evolution and structural response throughout the optimization process. Conclusions: The results demonstrate that GPU-accelerated topology optimization can provide mechanically interpretable and computationally efficient support for early-stage structural exploration. While limited to a simulation-only scope, the proposed workflow illustrates how interactive GPU-based tools can enhance structural insight and accelerate preliminary design decision-making without requiring high-performance computing infrastructure.

Critical Traverse Velocity Threshold for Through-Cut of 3 mm CFRP by Abrasive Waterjet: a Binary Logistic Model Based on Post-Cut Images

2025-11-11T10:59:40+02:00

Abrasive waterjet (AWJ) trimming of thin carbon fibre-reinforced polymer (CFRP) laminates faces the challenge of defining a reliable process window to ensure full penetration without costly metrology. This study establishes, for the first time, a statistically validated through-cut threshold for 3 mm quasi-isotropic T300/epoxy CFRP under standard industrial AWJ parameters (pressure: 200 MPa, abrasive mass flow rate: 120 g/min, standoff distance: 5 mm). Using only post-cut digital caliper measurements and photographic documentation—a low-cost metrology approach—a binary logistic regression model was calibrated from experimental data at three traverse velocities (300, 500, and 700 mm/min, n = 8 replicates each), yielding empirical through-cut probabilities of 1.00, 0.375, and 0.00, respectively. Firth’s bias-reduced penalised likelihood method was employed to address complete separation in the data, providing stable parameter estimates. The model identifies a critical traverse velocity of V₉₅= 292 mm/min (95 % profile-likelihood:276–308 mm/min) guaranteeing 95 % through-cut probability. This quantifies and validates the empirical shop-floor rule of "≤ 300 mm/min". The estimated transition zone width (~200 mm/min) is markedly narrower than that reported for ductile metals, attributable to the low interlaminar fracture toughness of CFRP, which precipitates abrupt, unstable delamination once jet energy flux falls below a critical level. Cross-validation demonstrated a predictive accuracy of 95.8 %. The study provides a robust, accessible framework for process window calibration in small-to-medium enterprises, bridging the gap between empirical practice and statistically controlled manufacturing for thin CFRP components.

Digital Twin Development of a Turning Machine for Designing a Stability Diagram

2026-02-28T10:24:58+02:00

The turning machining system as an object of study and the dynamic phenomena that constitute the problem that leads to the occurrence of vibrations are presented. The definition of a vibration-free cutting mode is proposed according to the stability diagram simultaneously for two components of the cutting mode – depth and feed. The mathematical model reflects the machining system as a three-mass one in the form of oscillatory links interconnected by negative feedbacks for elastic displacements and positive feedbacks through the delay function. A mathematical model has been developed in the form of a digital twin, due to its representation in state variables, which allows for modeling by numerical methods. Such a model is the basis of the created software, which allows predicting the behavior of the machining system in time and frequency spaces depending on the initial parameters of the machining system and the cutting mode. To ensure adequacy, the model uses dynamic parameters obtained by experimental modal analysis methods. The created software allows you to design stability diagrams of the machining system in the coordinates “cutting depth – speed” and
“feed – speed”. The design is carried out automatically according to the stability criterion, which is based on the analysis of the location of the frequency response hodograph on the complex plane. The adequacy of the developed mathematical model and the created procedures for automatic design of the stability diagram is experimentally confirmed by comparing theoretical results and the roughness of the machined surface. The developed digital model and software allow you to choose a vibration-free cutting mode, which guarantees the required quality of machining at maximum productivity.

Improving the Positioning Accuracy of a Multi-Link Parallelogram Mechanisms

2026-03-11T09:29:54+02:00

The object of study is a pantograph mechanism of packaging equipment designed for the synchronous movement of multiple carriages along guides. The mechanism structure consists of serially connected parallelogram sections, where motion is transmitted through a system of hinged joints.

The research problem relates to the decrease in carriage positioning accuracy due to clearances in the hinged joints of the multi-link mechanism. In mechanisms with a large number of sections, even minor clearances lead to progressive error accumulation and deviations of the actual carriage position from the calculated one, which is critical for reconfigurable dosing lines.

The study investigates the influence of joint clearances on the kinematic characteristics of the pantograph mechanism. A compr-

?hensive approach was applied to analyze accuracy, including: mathematical modeling for analytical kinematic description using the vector loop method; geometric modeling in a CAD system, which allowed for the determination of limiting carriage deviations upon reaching the physical clearance limits in joints; and a full-scale experiment using a physical prototype. It was established that for a five-section mechanism, the maximum positioning deviation is 9–12 mm, caused by the sequential summation of backlashes in the kinematic pairs.

The results obtained show that the error magnitude increases non-linearly depending on the section opening angle. A comparison of the mathematical modeling results and the geometric CAD modeling data demonstrated high convergence (with deviations within 6.4–8.2%). It was established that a symmetrical arrangement of sections relative to the central point of the mechanism provides partial compensation for accumulated errors and allows for a two-fold reduction in the total carriage position deviation compared to a one-sided linkage scheme.

A distinctive feature of this study is the comprehensive approach combining analytical methods, numerical modeling, and physical experimentation, which enabled the identification of error accumulation patterns and the justification of conditions for their minimization. The proposed methodology allows for the elimination of accuracy constraints during the design phase for mechanisms containing up to 6 actuating units.

The obtained results were used in the analysis of the pantograph mechanism design for packaging equipment and can be applied during the design and modernization of complex multi-link systems where high-precision synchronous movement of multiple working elements is required.

Normative and Methodological Support for the Life Cycle of Science-Intensive Products: Integrating Systems Engineering And Project Management

2025-10-06T15:43:36+03:00

Ukrainian high-tech manufacturing enterprises face a persistent gap between the national regulatory–methodological framework for life-cycle (LC) management and the requirements of global markets and certification. The problem stems from limited coverage of late LC phases, terminological inconsistency, and fragmented adoption of digital tools (PLM, MBSE, Digital Twins), which complicates alignment with international frameworks (ISO/IEC/IEEE 15288, ISO 2150x series, ECSS, AAP) and PMI/INCOSE practices. The aim is to develop an implementation-ready model, harmonized with international standards, that integrates Systems Engineering (SE) with Project/Programme/Portfolio Management (PPPM) while enabling a robust digital thread and transparent decision-making. The methodology comprises a comparative analysis of international and national normative documents, process modelling of the LC with Decision Gates, construction of mapping tables, and synthesis of a cross-project plan set. The results deliver a reference architecture for SE–PPPM integration; three application profiles (L/M/H); organizational roles and institutions; a digital infrastructure; a 12–24-month implementation roadmap; and a metrics system. The conclusions indicate that the proposed model bridges methodological gaps, increases LC governance and traceability, shortens time-to-market, and facilitates compliance with EASA/FAA/EN 9100/AQAP. The practical contribution is a set of typical recommendations and harmonization tools for enterprises in Ukraine’s aerospace and defense manufacturing sectors.

Effect of thermal ageing on mechanical, and fracture properties steels of nuclear power plant: a review

2026-03-20T11:58:05+02:00

Most of Ukraine’s nuclear power plant units have reached the end of their design life (30 years), which, in the context of the transition to long-term operation, increases the risk of accidents due to the degradation of structural materials. The introduction of the ageing management concept in the nuclear industry and the tightening of regulatory requirements necessitate a comprehensive study of ageing mechanisms, in particular a quantitative assessment of their impact on the strength and fracture resistance characteristics of equipment beyond its design life.

The aim of this work is to analyse scientific research on the impact of long-term thermal ageing on the mechanical properties and fracture parameters of reactor plant materials.

The review examines global experience in ageing management, analyses temperature-time operating conditions, and provides a detailed description of the evolution of the microstructure and mechanical properties of the main types of reactor steels: low-alloy, austenitic, austenitic-ferritic, martensitic and martensitic-ferritic. Understanding thermal degradation processes is crucial for the informed selection of materials, the prediction of their remaining service life, and the assurance of long-term safe operation of nuclear power plants.

The search and selection of sources was carried out in the scientometric databases Scopus, Web of Science and Google Scholar for the period 2010–2025. This made it possible to summarise current experimental data and approaches to predicting the residual life and ensuring the operational reliability of nuclear power plants.

Inverse Problems and Their Use for the Design of Aviation Navigation Equepment

2025-12-18T13:35:36+02:00

The article proposes a method for determining the maximum thermal load from the temperature (thermal) stress measured with a certain error by solving the inverse problem of thermal conductivity and thermoelasticity. The determination of the maximum thermal load in the same way as the regulation of external and internal temperature and power loads, at which the temperature stresses or displacements in the structural elements within acceptable limits are achieved, are of significant theoretical value and are of great practical value, namely for non-destructive testing tasks. An expedient way of finding these quantities as a function of time and geometric coordinates is to solve the inverse problems of thermal conductivity and thermoelasticity, i.e., to determine the temperature field based on the field of temperature stresses. To obtain a stable solution to the inverse problem of thermoelasticity, A. N. Tikhonov's method is used with an effective search for the regularization parameter. The functional of A. N. Tikhonov reflects the deviation of the temperature stress obtained as a result of observation from that calculated on the basis of an approximate solution of the direct problem of thermoelasticity by the finite and boundary element’s methods. In this functional, the stabilizing functional with the regularization parameter is used as the term to the square of the indicated deviation. The search for the regularization parameter is carried out using an algorithm similar to the search algorithm for the root of a nonlinear equation. The use of influence functions in the method allows one to represent temperature and temperature stress depending on the same vector, which greatly facilitates the implementation of the iterative process. The proposed method allows, without bringing the research object to failure, to determine the load at which it will be destroyed i.e. this problem of non-destructive task. The-effectiveness of this method lies in the fact that its application reduces the cost of complex experimental studies of objects and eliminates the need to create analytical methods that accompany these studies.

EUROPEAN AND AMERICAN INVENTIVE CLAIMS. ASPECTS OF STRUCTURE AND IMPLICATIONS

2026-02-16T17:54:49+02:00

Against the backdrop of globalisation in the global innovation sphere, in particular the growing share of foreign funding of scientific research in most countries, there is a need to consider the possibility of patenting one’s own research in other countries.

The most common object of intellectual property rights created as a result of scientific and technical research is an invention or a utility model, the technical essence and scope of rights of which are defined by the claims of the invention (utility model).

The purpose of this article is to analyse invention claims under the legislation of Ukraine, the United States, and the European Patent Convention, as well as to identify the specific features of such claims. The article examines common and distinctive aspects of claim structure, the advantages and disadvantages of using multi-part (multi-claim) formulations, and provides relevant recommendations for applicants. The information from this research may be useful for applicants who file applications in Ukraine and intend to subsequently obtain legal protection beyond the borders of our state.