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Application of machine learning in the precise and cost-effective self-compensation of the thermal errors of CNC machine tools – a review

Czwartosz Robert, Jedrzejewski Jerzy

Journal of Machine Engineering

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2022

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Vol. 22, No. 3

59--77

EN

The current development of production engineering takes place through the innovative improvement of machine tools and machining processes at the constantly growing application of intelligent self-improvement functions. Machine learning opens up possibilities for machine tool self-improvement in real time. This paper discusses the state of knowledge relating to the application of machine learning for precise and cost-effective thermal error self-compensation. Data acquisition and processing, models and model learning and self-learning methods are also considered. Three highly effective error compensation systems (supported with machine learning) are analysed and conclusions and recommendations for future research are formulated.

2

Research on forced cooling of machine tools and its operational effects

Jedrzejewski Jerzy, Winiarski Zdzislaw, Kwasny Wojciech

Journal of Machine Engineering

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2020

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Vol. 20, No. 2

18--38

EN

The aim of this paper was to analyse in depth the existing research on the effectiveness of forced cooling and the directions in its improvement and development against the background of the increasing needs of machine tools and machining processes. The forced cooling methods used and their importance from the point of view of the development of machine tools are discussed. A detailed review of the state of the art in this field, including the latest research reports, is carried out. The essence and methods of forced cooling parameters improvement through holistic modelling, numerical simulations and optimization are presented. Moreover, the currently achievable effectiveness of forced cooling is illustrated with the results of the research conducted by the authors. Finally, conclusions are drawn and suggestions concerning the future research in this field are put forward.

3

General directions in contact modelling development

Maciolka Pawel, Jedrzejewski Jerzy

Journal of Machine Engineering

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2019

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Vol. 19, No. 4

91--109

EN

This paper presents a survey of works, selected from the period of the last twenty years, on deformations in the contact between rough surfaces. All the selected works use FEM. They deal with the modelling of individual contact asperities or the use of experiment to verify contact models. First, research directions connected with the modelling of single asperities, whose shape is usually approximated with that of a hemisphere or a half cylinder, are presented. Section 3 discusses research directions concerning models which include the layer under asperities, and models for small contact surfaces (about 1 mm2). Section 4 reviews directions in contact modelling which takes into account neighbouring asperities and laterally loaded asperities. Section 5 discusses directions in the development of models and experiments used or suitable for verifying models. Finally, conclusions concerning accurate contact deformation modelling are presented.

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CNC machine tool error compensation system implementation strategies and their constraints

Medyk Pawel, Jedrzejewski Jerzy, Kasprzak Marcin

Journal of Machine Engineering

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2019

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Vol. 19, No. 4

70--81

EN

This paper deals with the constraints imposed on error compensation systems by their implementation strategies. Constraints stemming from the structure of the control system with an NCK architecture of the ADCBI type are presented. Practical realizations of compensation and potential solutions offered by contemporary commercial CNC controllers are discussed.

5

Ball screw unit precise modelling with dynamics of loads and moving heat sources taken into account

Jedrzejewski Jerzy, Kowal Zbigniew, Kwasny Wojciech, Winiarski Zdzislaw

Journal of Machine Engineering

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2019

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Vol. 19, No. 4

27--41

EN

This paper deals with the precision modelling of the ball screw unit’s thermal behaviour in the turning centre and its impact on the tool head positioning error. The error components along controllable axes X and Z are described in detail using an FE model integrating the changes in thermal and force loads and deformations occurring during the motion of the nut as a heat source. The impact of the nut work cycle on the thermal deformations of the ball screw and the displacements of the slideways and the screw points along both the axes and on carriage positioning precision is demonstrated.