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Found 6374 publications

Investigation of FDM-Based 3D Printing for Optimized Tooling in Automotive and Electronics Sheet Metal Cutting

Szabolcs Fischer Szabolcs Szalai Mykola Sysyn Dmytro Kurhan Brigitta Fruzsina Szívós Vivien Nemes György Szabó

Publication Name: Applied Sciences Switzerland

Publication Date: 2025-01-01

Volume: 15

Issue: 1

Page Range: Unknown

Description:

Within the scope of the work, the possible use of fused deposition modeling (FDM) technology in executing rapid prototypes of cutting tools for aluminum sheets was systematically studied. Relevant investigations have thus far mainly concentrated on tools for the 3D printing of bent and deep-drawn pieces, yet the implementation of FDM tools in cutting has been insufficiently covered. This study aims to determine the characteristics of FDM cutting tools, such as wear and tear, dimensional stability, and cutting efficiency. Various tool designs were tested under different wall thicknesses and orientations with respect to the feed of Al99.5 sheets with thicknesses of 0.22 mm and 0.3 mm. According to the results, in the best case, three-dimensional printed PLA tools performed six cuts with no burrs and an acceptable wear level due to the IT tolerances (IT9 and IT10). Tools with thicker walls and more appropriate orientations were found to be more robust. However, some designs failed when subjected to greater loads, revealing a deficiency in some of the strength properties of the material. These observations suggest that it is possible to create 3D printed tools for modeling and small-scale production at considerably cheaper and faster rates than conventional methods. Future work will integrate advanced materials and designs to enhance tool performance, further solidifying FDM as a transformative approach in industrial tool manufacturing. With this research, the authors wanted to demonstrate that FDM technology can also be used to produce a classic sheet cut, which, of course, is still of great importance for prototyping or setting up production processes. This research demonstrated that FDM printing can play a role in this area.

Open Access: Yes

DOI: 10.3390/app15010442

Determination of center of gravity and moment of inertia using dynamic testing method

No authors available

Publication Name: "Advances in Acoustics, Noise and Vibration - 2021" Proceedings of the 27th International Congress on Sound and Vibration, ICSV 2021

Publication Date: 2021-01-01

Volume:

Issue:

Page Range: Unknown

Description:

The knowledge of a vehicle's center of gravity (COG) and moment of inertia (MOI) are important from vehicle dynamic and comfort points of view. These parameters can be determined from the CAD model of the vehicle, however, manufacturing inaccuracies and additional elements can modify the values, and experimental validation can be necessary. The determination of COG (and even MOI) can be carried out using classical physical methods, but a more convenient and sophisticated method is offered based on dynamic testing data. The method is known and accessible even in commercial testing software, but a clear recommendation for the optimal input data and the expected accuracy is still not available. The purpose of this study is to define the influencing factors of the measurement and quantify their effect. The introduced method is based on the evaluation of the frequency response functions in the mass-line region. Input data were obtained by using impulse hammer excitation and accelerometers for measuring the response of the structure. The measurements and the evaluations were performed in Siemens LMS Test.Lab software using Rigid Body Calculator module. The results of the dynamic measurement are compared to CAD data and to the COG value got from simple static measurement.

Open Access: No

DOI: DOI not available

Development of 1D and 3D acoustic simulation methods for transmission loss based on transfer matrix measurement results

No authors available

Publication Name: "Advances in Acoustics, Noise and Vibration - 2021" Proceedings of the 27th International Congress on Sound and Vibration, ICSV 2021

Publication Date: 2021-01-01

Volume:

Issue:

Page Range: Unknown

Description:

During the acoustical characterization of a component of a building, machine or vehicle, the normal incidence sound transmission loss is a major factor. Transmission loss simulation is also crucial in designing intake or exhaust elements, such as reflective mufflers. However, there is not enough information in the open literature about the applicable frequency ranges of experimental and 1- and 3D simulation methods. Therefore, the main purpose of this paper is to evaluate the frequency limits of computational and experimental transmission loss analyses of various reflective mufflers. For the validation two in-house impedance tube test benches were designed and multiple measurement setups were investigated. The combination of the four-pole matrix and the two-load methods was used during the experimental part of the study. In order to obtain appropriate transfer function results, distinct setups were evaluated, such as a low-frequency sound source with bigger tube diameter and a high-frequency sound source with smaller tube diameter. The low-frequency setup is suitable for the investigation of the system in the range of 30-500 Hz. The high-frequency setup is capable of measuring from 300 Hz to 2000 Hz, which is the upper frequency limit of the range of interest. Consequently, the in-house system is suitable for measuring the transmission loss in the 30-2000 Hz frequency range. 1D simulations were performed using Ricardo Wave software and 3D simulations were carried out in the STAR-CCM+ software. The upper cutoff frequency of 1D simulation method was determined to be 1500 Hz according to the correlation with the measurements. The frequency range of simulation could be extended up to 2000 Hz by employing 3D simulation for transmission loss calculations. This paper gives insights into the transmission loss measurements with the in-house system and the correlation analysis with different simulation methods.

Open Access: No

DOI: DOI not available

Collecting public transport passenger preference data online

Ágoston Winkler

Publication Name: Pollack Periodica

Publication Date: 2010-08-01

Volume: 5

Issue: 2

Page Range: 119-126

Description:

Passenger preference analysis is an important area of transport modeling. Passengers value public transport journeys in several ways: their opinion depends on many factors. The relative importance of these features is often characteristic to certain passenger groups. Knowing the distribution of the passengers and their preferences makes it possible to improve transport models and simulation techniques. The paper provides an overview of existing revealed and stated preference analysis methods and the results of some former surveys carried out in Gyor, Hungary. Then it proposes a new method for detecting passenger preferences by integrating data collection into an online journey planning service.

Open Access: Yes

DOI: 10.1556/Pollack.5.2010.2.12

Random forest regression on pullout resistance of a pile

Edina Koch Shaymaa Alsamia

Publication Name: Pollack Periodica

Publication Date: 2024-10-16

Volume: 19

Issue: 3

Page Range: 28-33

Description:

This research aims to study the pullout resistance of a helical pile using three methods of machine learning techniques, which are: random forest regression, support vector regression, and adaptive neuro-fuzzy inference system, based on experimental results of a helical pile. The performance of these three techniques has been d compared and the results show that random forest algorithm has best performance than neuro-fuzzy inference system and support vector technique. The results show that machine learning considered a good tool in terms of estimating the pullout resistance of helical piles in the soil.

Open Access: Yes

DOI: 10.1556/606.2024.01052

A tool for creating and editing dashboards in VR spaces based on a canonical set of operations

Adam Csapo Tarek Setti

Publication Name: 11th IEEE International Conference on Cognitive Infocommunications Coginfocom 2020 Proceedings

Publication Date: 2020-09-23

Volume: Unknown

Issue: Unknown

Page Range: 497-502

Description:

VR spaces are increasingly used for purposes other than entertainment, to help communicate ideas in more memorable and effective ways. This paper focuses on the problem of how 2D panel layouts - i.e. information dashboards - can be effectively created and edited in 3D spaces. We propose a set of canonical operations to support such layout design. We also introduce a pilot implementation that enables the use of these operations to help configure 2D content within spaces running on the MaxWhere VR platform.

Open Access: Yes

DOI: 10.1109/CogInfoCom50765.2020.9237857

Development of tire-road noise measuring system

No authors available

Publication Name: "Advances in Acoustics, Noise and Vibration - 2021" Proceedings of the 27th International Congress on Sound and Vibration, ICSV 2021

Publication Date: 2021-01-01

Volume:

Issue:

Page Range: Unknown

Description:

In vehicles there are 3 main noise sources: powertrain noise (e.g. engine, gear engagement or exhaust noise), aerodynamic noise (or wind noise), and the noise from the tire-road contact. The first two are traditionally in the primary focus of vehicle manufacturers, however, due to both the already made powerful developments and the spreading of electric vehicles, the rolling noise is gaining more and more attention during the vehicle development process. There are two major influencing factors of this noise source: tire (geometrical and material) characteristics and road (surface) characteristics. The separation of their contribution is not straightforward, investigated rarely, and the requirements of homologation standards do not expect it neither. However, if one would like to meet the new vehicle pass-by noise regulations, it is more and more inevitable to have a sophisticated break-down of rolling noise. A straightforward solution is the usage of a one-wheel testbench developed directly for acoustical measurements. Such design process is presented in this paper, where the most important requirements are: enabling the users to compare tires from acoustical aspect under totally objective conditions, modelling the typical conditions of vehicles and ensuring data for rolling noise simulations. One further functionality of the testbench is to reproduce the real rolling noise by mounting realistic road surface sections onto the superficies.

Open Access: No

DOI: DOI not available

NVH characterization of a ladder-like welded structure using finite element analysis and experimental method

No authors available

Publication Name: "Advances in Acoustics, Noise and Vibration - 2021" Proceedings of the 27th International Congress on Sound and Vibration, ICSV 2021

Publication Date: 2021-01-01

Volume:

Issue:

Page Range: Unknown

Description:

In vehicle industry, considering a chassis, the evaluation of the experimental modal analysis is usually done up to 80 Hz, since the modal density is increasing with frequency. In addition, the deviation between the measurement and simulation is getting more significant at higher frequencies. The purpose of this study is to extend the usable test range and to improve the accuracy of the results both in case of measurement and FE (Finite Element) simulation. Present paper introduces the vibrational characterization of a ladder-like welded structure. This test case represents a simplified model of a vehicle's frame consisting of rod-like elements with high stiffness, connected to each other in welded junctions. Although such simulational and experimental modal analysis procedures are widely used in practice, results can significantly change according to the used method and the fine-tuning of parameters. For this reason, a further goal is to find the best measurement and simulation technique for the given structure. During the FE analysis different modelling solutions and element types were compared. In order to discover the effect of the manufacturing inaccuracies, the same measurements were performed on two distinct, but theoretically identical samples. The influence of the experimental setup (e.g. excitation and fixing method) and settings were investigated as well. Finally, FE simulation and experimental results are compared using Frequency Response Functions.

Open Access: No

DOI: DOI not available

Beyond 160 applications of an expert system: Key to a better usability

Gabriella Toth-Haasz Zoltán Baracskai

Publication Name: 11th IEEE International Conference on Cognitive Infocommunications Coginfocom 2020 Proceedings

Publication Date: 2020-09-23

Volume: Unknown

Issue: Unknown

Page Range: 563-568

Description:

The most influential relevant thinkers have complained of the 'poverty' of Expert Systems (ES) both in the past (Dreyfus and Dreyfus, 1986) and in recently studies as well (Müller and Bostrom, 2016). We developed our own AI-Based Expert System shell for rule-based and case-based reasoning three decades ago and now there are 160 Knowledge Engineering (KE) process behind us with this system. We hope that this experience give us the right to formulate an opinion about that what is the key to a better usability and user experience in understanding of the result of the decision making process. While we do not think that ES is an omnipotent panacea, we also do not think that its applicability is determined only by the shell capabilities. However, one ability is essential; namely, presenting the result as simply as possible in order to that the decision-maker also can understand it. Our finding is that ES shells are only able to be transparent if they are designed by people who have an understanding of the human thinking process instead of a strong math-based software development approach.

Open Access: Yes

DOI: 10.1109/CogInfoCom50765.2020.9237822