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25.04.2024

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Reducing of process model uncertainty towards smart machining systems

Neven Trajchevski, Mikolaj Kuzinovski, Mite Tomov, Piotr Cichosz

Smart machining system architecture [3]

Smart machining system architecture [3]

This paper presents an approach of empirical modeling of cutting process physical phenomena with measurement uncertainty parameters accompanied to the model exponents/ /coefficients. The approach is presented trough an example of creating a power mathematical model for average cutting temperature in turning with details about the uncertainty contributions from different experimental plans. The approach is proposed to be implemented as usual practice during empirical modeling, in order the resulting models to fit with the needs of the smart machining systems and the needs of interoperability between researchers.

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Checking the accuracy of selected methods of probe radius correction

Marek Magdziak, Marcin Krawczyk, Andrzej Kawalec, Jerzy Sładek

Algorithm for assessment of the accuracy of two selected methods of probe radius correction

Algorithm for assessment of the accuracy of two selected methods of probe radius correction

The paper concerns the analysis of accuracy of two methods of probe radius correction which are based on Bézier curves. Those methods can be applied in the case of measurements of free-form surfaces. The analysis of accuracy of selected methods was done in relation to reference corrected measured points.

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Supporting the decision during inter-operational inspection of the electrodes based on the ensemble of neural networks

Halina Nieciąg, Rafał Kudelski, Krzysztof Zagórski

The system consists of CNC electro discharge machine (Roboform 350 Sp GF Agie Charmilles) to manufacture the workpieces, 3R robot for loading workpieces and tools in and out of the machine and for using the identification cycles (Work Master robot) and CMM (DEA Global Performance, with measuring range 500×700×500 mm, resolution 1 µm)

The system consists of CNC electro discharge machine (Roboform 350 Sp GF Agie Charmilles) to manufacture the workpieces, 3R robot for loading workpieces and tools in and out of the machine and for using the identification cycles (Work Master robot) and CMM (DEA Global Performance, with measuring range 500×700×500 mm, resolution 1 µm)

In this paper the method based on the ensemble of artificial neural networks is presented for prediction of the geometrical quality of workpieces after electro-discharge machining (EDM). The complexity and random nature of physical phenomena accompanying the EDM process excluded the theoretical ways. The working electrodes were measured using CMM in flexible manufacturing system. The data obtained from inter-operational measurements were used for the neural networks training. Commonly used measures to express the tool wear turn out to be useless due to their large uncertainty. The tool monitoring and the ensemble method provided more stable diagnosis of the condition of the tool.

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Technological properties of metallic-diamond tools manufactured by SPS process

Elżbieta Bączek

Sintering furnance HP D125 SPS (a), sintering chamber with graphite elements (b)

Sintering furnance HP D125 SPS (a), sintering chamber with graphite elements (b)

This paper presents the results of the technological properties of impregnated diamond tools fabricated via spark plasma sintering (SPS) during the process of grinding and cutting of high purity oxides ceramics (ZrO2) stabilized with Y2O3 or MgO. As a metal matrix the water atomized tin bronze and steel-based matrix was used. After sintering, an analysis of microstructure was conducted using scanning electron microscopy. The resulting materials were tested for the apparent density determined by Archimedes’ method, Rockwell hardness (scale B), Young’s modulus, as well as for the technological properties. The performance results of obtained diamond composites were compared with commercial diamond wheel fabricated by HP (hot pressing), usually employed in the grinding of ceramics. Results showed that diamond tools based on Cu-Sn and steel, obtained by SPS, may be successfully used as a matrix in the impregnated diamond tools for cutting or grinding of high-purity oxides ceramics.

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Evaluation of possibilities of application of web-based tool for effective identification of mechanical properties of materials

Łukasz Wolski, Magdalena Kopernik

A main template of the web application GUI: 1 – a navigation bar, 2 – a view content and 3 – a dock menu

A main template of the web application GUI: 1 – a navigation bar, 2 – a view content and 3 – a dock menu

The main purpose of the work is to present and test the developed web-based tool to identify parameters of rheological equations, whose functionality according to the presented results is comparable to existing desktop applications. The developed web-based application with a user-friendly interface uses selected optimization methods (Powell and Hooke-Jeeves algorithms). Criteria for selecting optimization methods are: robustness and frequent application to identification problems described in literature. Testing the developed application consists of comparing the identified stress-strain curves obtained from mechanical tests using the developed tool and commercial desktop application, and performing efficiency tests for the analyzed examples of rheological equations and optimization methods. For this purpose, two material models were used: a simple Hollomon’s model and a multi-parameter model used for steel, in which the influence of softening during the dynamic recrystallization is insignificant. The presented software is implemented in technologies such as JDK 1.8, Spring Framework and PrimeFaces, and passes the efficiency tests successfully.

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The direct solid method of geometry analysis of the globoidal worm gear with the rotary teeth

Patrycja Ewa Jagiełowicz

Temporary tooth contact – the worm

Temporary tooth contact – the worm

The tooth contact analysis (TCA) in the wheel rotation function of the globoidal worm gear with rotary teeth was presented. To determine the contact in CAD system, the direct solid method of geometry analysis was used. In the gear the globoidal worm gear was used, and the classical worm wheel was replaced by the wheel with rotary teeth in the shape of the frustum of cone.

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