Ignat'ev Aleksandr Anatol'evich, Doctor of engineering science, professor, head of sub-department of automation, control, mechatronics, Saratov State Technical University named after Y. A. Gagarin (77 Politeknicheskaya street, Saratov, Russia), email@example.com
Karakozova Anna Vladimirovna, Postgraduate student, Saratov State Technical University named after Y. A. Gagarin (77 Politeknicheskaya street, Saratov, Russia), firstname.lastname@example.org
Background. Monitoring system of technological processes (MSTP), including equipment and processing, has an important role in the overall structure of the system of quality control, especially when it comes to manufacturing of articles of precision engineering and instrumentation. At monitoring of the technological equipment’s state, diagnostics, performed at idle, and choosing theprocessing mode individually for each machine it is necessary to carry out automatic control of the dynamic state of each machine prior to treatment and processing of the vibration level. The relevance of the automatic control of grinding consists in just quick identification of irregularities at processing, but also in prevention of defective parts occurrence.
Materials and methods. The authors developed an information-functional model of a grinding machine for bearing rings processing, which gives an idea about the measured vibro-acoustic parameters (VA), bound to a functional circuit. The article considers a possibility of deteriming a rational gringing mode for bearing rings’ rolling surfaces based on the measurement of vibro-acoustic oscillations of the dynamic system. The authors used the methods of the control theory to calculate the transfer function of a closed dynamic system with different tool feed and circle wear. The researchers determined the stability margin of the dynamic system of machines by an oscillation index or by the Mikhailov criterion.
Results. Based on the processing results of VA fluctuations the authors established a connection between the stability margin and circle wear in automatic CNC grinding machines Weiss WKG-05, and between the stability margin and the quality of surface layer prcessing in the grinding machines SIW-4, SIW-5 defined at different feed rates. This allowed to determine the rational supply, at which the dynamical system has the highest stability margin, and also the expedient moment for wheel dressing. These data are needed to build the database and knowledge base of the expert system, which is a part of MSTP.
Conclusions. The researchers developed and tested a method for determining an appropriate processing mode, based on identification of the dynamic system of the machine when cutting. The authors also substantiated the choice of informative parameters of VA oscillations to assess the dynamic state of the machine at cutting and without cutting.
grinding, vibro-acoustic oscillations, supply range, circle wear, transfer function, autocorrelation function, stability margin, informative parameters.
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