Том 47, № 5 (2018)

This article is a modest tribute to the scientific heritage of V.O. Kononenko, whose scientific works formed a new area of mechanics—systems with limited excitation. The development of this area has led to study of the most typical modes of interaction such as chaotic interaction. Recently, the number of studies of the problems of dynamics in limited excitation systems in international research centers has grown, which indicates the relevance of these problems. A number of new areas of research of this particular kind of systems (in biophysics, celestial mechanics, rocket engineering, etc.) have arisen.

The various problems of modern machine science related to the requirements made on the created devices for different purpose are analyzed: processing and medical robots, measuring and testing devices, training simulators, and manipulators for corrosive media.

The results of experimental studies of the kinetics of damage accumulation at the stages of formation and rates of development of cracks in cyclic loading of the cyclically hardening AD-33 aluminum alloy are presented, and an assessment is made of the levels accumulated in the process of loading of damage on the basis of the deformation and kinetic criteria. It is shown that the limiting state (final fracture) during cyclic loading of an aluminum alloy is described well when using deformation characteristics (cyclically reversible deformations and one-sided accumulated ones at the stage of formation, and reversible and one-sided accumulated displacement of crack edges at the stage of crack development) used in the deformation and kinetic criteria. It has been established that a cyclically hardening aluminum alloy at the stage of crack development under tension-compression conditions does not obey the first model of fracture mechanics.

Finite element modeling of the deformation and fracture processes in a composite anisogrid (network) structure made of carbon fiber reinforced plastic (CFRP) with different types of deformation has been performed. The anisogrid structure is based on a longitudinal set of ribs supported by diagonal sets of ribs directed at angles of about ±45° with respect to the longitudinal ribs. Based on the model of mechanical property degradation for composite material layers strength analysis of the structure has been performed taking into account the process of damage accumulation in the course of loading. The maximum destructive load is determined and the fracture pattern is obtained for each type of deformation. The determining impact of the rib-crossing zones of different directions as the foci of progressive destruction of the entire anisogrid structure is established.

Further development of calculation and experimental analysis methods and ensuring their security against risk criteria for the prevention of accidents and disasters is considered. Of particular importance in this direction are the methods and technologies of both computational and physical modeling and analysis of the limiting states of structures leading to catastrophic failure. It is shown that the most promising direction of creating an effective apparatus for risk assessment and analysis of the security of technical systems can be considered the use of hybrid methods that allow taking into account both stochastic and interval uncertainties of the risk parameters in determining the safety and security conditions of man, the technosphere, and nature from manmade accidents and disasters.

This paper describes an upgraded installation, a procedure, and results of lubricants testing with respect to use in the executive mechanisms of space vehicles.

The use of wave generators to intensify the processes of mixing and metering model energy condensed systems is studied. The urgency of this problem is specified by the imperfection of the traditional mixers and metering devices of the system components. The mathematical modeling of the wave action is performed for some model technological processes of processing and metering systems. According to the results of mathematical modeling, the preliminary parameters are estimated and new mixers and meters are developed ensuring more efficient modes of mixing and accurate vibration metering of the model energy systems.