PSI - Issue 20

E.F. Dubinin et al. / Procedia Structural Integrity 20 (2019) 103–107 E.F. Dubinin and V.I. Kuksova / Structural Integrity Procedia 00 (2019) 000 – 000

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1. Introduction Transition to the concept of acceptable risk level of functioning of the complex technical systems (CTS) demanded development of the systems of technical diagnostics (STD) as their necessary element. The use of anticipatory diagnostics allows to detect beforehand the situations leading to failure of the equipment, violation of technological process, to emergency stop or the accident itself. Assessment of operating modes of technological equipment, determination of levels of danger and consequences of possible accidents assumes inevitable use of fuzzy (interval, score, linguistic) estimates. Use of methods of fuzzy logic provides a possibility of receiving quantitative estimates of the technical condition of equipment and CTS in general in multidimensional space of fuzzy variables, by Akhmetkhanov et al. (2018). current value of the i -th parameter characterizing the state of OD accept maximum acceptable value of the i -th parameter characterizing the state of OD x i opt optimal value of the i- th parameter for accident-free functioning of OD a i significance (weighting factor) of the i -th parameter n number of parameters included in diagnostic model Y some state of the diagnostic object Features of methods of fuzzy logic limit its application at diagnostics of a number of malfunctions: which very quickly turn into accident; The field of application of models based on methods of fuzzy logic is diagnosing of the malfunctions developing relatively slowly or which are found out at an early stage that practically excludes the probability of their sudden transition to accident. Now there is no uniform standard and methodical base defining standard stages of creation of the models using methods of fuzzy logic. 2. Stages of development of STD based on fuzzy logic methods 2.1. Creation of information model of the object of diagnosis (OD) As diagnostic models use the differential and algebraic equations, logical ratios, matrixes of nodal provodimost, functional, structural, regression and other models allowing to connect parameters of technical condition with the general state of an object. 2.1.1. Inspection and analysis of OD, the result of which is an informational description of the set of functional and test parameters of control of OD Informationally, any state of a complex object can be characterized by a variety of variables (parameters) of different nature: analog, discrete and calculated, as well as values of time of carrying out measurements. The frequency of collection of indicators and carrying out calculations is determined by dynamics of behavior of the object of control and management. x i which too late may be found by means of the available diagnostic aids; nature and rate of development of which cannot be reliably predicted. Nomenclature x i