Design of Machines and Structures

ADDITIVE MANUFACTURING FROM BIOMIMETIC APPROACH

Ágnes Takács — 2024-06-21

During the past millions of years since the beginning of our world, nature has created structures that are resistant to the various effects of the environment. However, these natural structures are quite complicated, so their production and artificial reproducibility with the tools of traditional manufacturing technology is a very difficult task. However, even complex structures can be produced relatively easily with the help of additive manufacturing. Using topological optimization techniques, lattice structure models with excellent mechanical characteristics can be created, which can be easily manufactured by exploiting the advantages of additive manufacturing. Applying natural structures (biomimetic approach) during topological optimization and produce the solution by additive manufacturing, light and high-strength structural alternatives can be created, any further structural analyses can be done.

CHRONICLES OF THE SEA

Rubina Colombo — 2024-06-21

This publication attempts to present the history of the sailing ships development, from ancient times to the present day. It is almost impossible to present the development history of such an important technological achievement in a few pages, so we only focus on the most significant turning points in the publication. We present the ancient ships, the long ships of the Vikings, the shipbuilding techniques of the age of great geographical discoveries. We analyse the characteristics of line of ships, which greatly influenced the battles of the great powers of the world. Finally, we give a small overview of currently used sailing ship technologies.

CONSTRUCTION OF THE CONTACT ZONE OF A HELICAL CYLINDRICAL EXTERNAL GEAR PAIR WITH STRAIGHT TOP LAND MERIDIANS

Zsuzsa Drágár — 2024-06-21

The study deals with the construction of the contact zone of helical cylindrical external gears. The shape and size of the contact zone determine the phenomena that occur even in the case of error-free tooth design, installation error exemption and load-induced error exemption Such a phenomenon is the vibration excitation resulting from the connection, which also affects the identification of the drive elements. It is possible to deviate from the regular rectangular shape of the contact zone by modifying the top land surfaces. The change can mean a combination of the change in the total length of the contacting generating lines and the change in the contact ratio. This study deals with the construction of the generalized contact zone.

INVESTIGATION OF REMESHING PARAMETERS FOR DEVIATION ANALYSIS IN REVERSE ENGINEERING

Péter Ficzere — 2024-06-21

The use of additive manufacturing technologies in industry is increasingly common, particularly with the emergence of Industry 4.0. These technologies can produce parts quickly and efficiently, but they also place higher demands on the quality of the manufactured products. The layer-by-layer processes create an anisotropic material model, which complicates component sizing. While the topic has been extensively researched, surface anisotropy has received less attention. The surface quality of a product may be affected by various factors, including the file conversion process or the staircase effect generated by the technology. Manufacturing parameters, such as layer thickness and orientation, can also have an impact. This paper focuses on the impact of reverse engineering step adjustment on surface quality.

THE EVOLUTION OF PRINTING

Maddalena Pizzeghello — 2024-06-21

The history of printing is a captivating narrative that has significantly influenced the dissemination of knowledge and the development of human society. This article explores the prehistory of literacy, the emergence of writing systems, the tools used before the invention of printing, and the profound impact of Johannes Gutenberg's movable type printing press. It also discusses the challenges faced by printing technology over the centuries, the role of digitalization, and the enduring value of traditional printing.

RESEARCHING THE GEOMETRIC LIMITS OF 3D LASER SCANNING

Ferenc Sarka — 2024-06-21

The paper presents the geometrical properties of those surfaces that can be digitized by 3D laser scanners. First the circumstances of the experiment are described. The device (Roland LPX-1200) and applied software (Dr. Pizza) are also introduced, such as the brief historical development of 3D digitization. Based on the data found in the literature, all those problems are collected, that can emerge during 3D laser scanning. In order to find the limits of the scanner, a test specimen was designed with a variety of geometric elements (planes in different positions, curved surfaces (concave, convex), roundings and chamfers in different sizes and positions, holes of different depths and diameter). During the design of the test specimen, those properties that were developed for additive technologies were used. The test specimen was produced by milling technology (Roland MDX 650), and then scanning with different settings were performed on it. The experiment was carried out until the largest real surface was digitized. Based on the test, it was summarized which geometries can be fully or partially scanned. Finally, a recommendation to achieve the best possible result was formulated.

OPTIMIZATION OF MULTI-CRITERIA DECISION-MAKING FOR DENTAL IMPLANT SELECTION

Ágnes Takács — 2024-06-21

The long-term biomechanical performance of dental implants is significantly influenced by material composition, anticipated loads, and the geometry of the interface between the implant and the bone. This study applies multi-criteria decision-making methods to select an optimal construction strategy. Through finite element analysis, variables such as implant geometry and stress distribution during loading are integrated into the decisionmaking process. By processing the results of alternative implants, we ranked these alternatives using an Excel implementation of the VIKOR decision support method commonly used in the literature. Results indicate that the optimal stress distribution depends on the size and shape of the implant. Selecting symmetric fixation points and optimal distances may enhance implant stability and long-term performance.

PROPOSAL OF PARAMETER CONTROL DESIGNATION SYSTEM OF ADDITIVELY MANUFACTURED PARTS

Levente Wolarek — 2024-06-21

As additive manufacturing is getting more and more widespread, the need for a system regarding the technical documentation is getting more required. The tremendous amount of manufacturing parameters makes the performance of the part hard to assess. Same parameters are used with different names and there is no common knowledge of how these parameters affect the part precisely. We can find a serious amount of research data and results, but only a small portion of them is able to be compared because of the different measuring techniques or similar investigation of parameters. To be more effective with the data gathering, a systematic way of recording these aspects is needed. In this article we propose a robust way of recording information on technical drawings of additively manufactured parts. We also discuss the difficulties and future opportunities implemented by this method.