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Abstract. ITL Inc. through its 30 years of activities in space exploration developed a number of unique processes for impairing new properties to space-bound materials that are exposed in LEO, GEO and planetary environments to space factors like atomic oxygen, ultraviolet radiation, charged energetic particles, etc. For materials flown in LEO missions, the atomic oxygen remains the major hazard. We developed a number of surface modification processes like Photosil, Implantox to change the surface structure of many polymer materials and paints and make them atomic oxygen resistive. For systems operating in GEO orbits the charging effects are among the major hazards. Two surface modification processed developed by ITL successfully solved these problems, while keeping the RF transparency of materials where necessary.

A comparison of natural trickle ventilation with a constantly opened window, forming a small vent opening, versus short-term ventilation performed by a briefly wide opened window has been made using CFD. It is shown that the value of energy efficiency of the short-term ventilation can be both positive and negative depending on the intensity and frequency of its realization. The nomogram of energy efficient usage of the periodic short-term ventilation has been developed on the results of physical experiment.

Approximate methods of computing the unsteady ventilated partial cavities created on both the plane and the cylindrical streamlined surfaces have been developed. The cases of plane partial cavities past a slender wedge-shaped cavitator, and axisymmetric partial cavities past a ring flange on the surface of an infinite circular cylinder are considered. Results of computer simulation of the unsteady ventilated partial cavities of both that types are shown. A comparison of the unsteady behavior of plane and axisymmetric ventilated partial cavities is given. A comparative analysis of two methods of controlling the partial cavities by varying the cavitator shape and by regulating the gas supply rate into a cavity is given. It has been shown that the first method is more effective for a partial cavity on a plane. For an axisymmetric partial cavity on a cylinder, both the control methods appear ineffective.

The operation reliability and service life of various heat engineering equipment: turbines, steam generators, heat exchangers, valves and control valves, pumps, etc. largely depends on the degree of wear of the working surfaces of highly loaded machine elements, particularly working blades of steam turbines and compressors of gas turbine engines (GTE) and gas turbine units (GTU).

The content of this book is based on the 3rd International Conference on Design, Simulation, Manufacturing: The Innovation Exchange (DSMIE-2020), held on June 9-12, 2020, in Kharkiv, Ukraine. This book reports on topics at the interface between manufacturing, materials, mechanical, and chemical engineering, with a special emphasis on design, simulation, and manufacturing issues. Specifically, it covers the development of computer-aided technologies for product design, the implementation of smart manufacturing systems and Industry 4.0 strategies, topics in technological assurance, numerical simulation, and experimental studies of cutting, milling, grinding, pressing, and profiling processes, as well as the development and implementation of advanced materials. It covers recent developments in the mechanics of solids and structures, numerical simulation of coupled problems, including wearing, compression, detonation, and collision, chemical process technology, including ultrasonic technology, capillary rising process, pneumatic classification, membrane electrolysis, and absorption process. Further, it reports on developments in the field of heat and mass transfer, energyefficient technologies, and industrial ecology. The book provides academics and professionals with extensive information on trends, technologies, challenges, and practice-oriented experience in the areas mentioned above.

Recognizing the practical need to control the cutting process, leading firms in the high-tech market began to offer software products that, in the automatic mode, were said to be able to calculate the optimal cutting mode. Currently, the most advanced technology is called iMachining, which means intelligent Machining. The article presents an analysis of the control, automatically designed in the iMachining Solid CAM module, for machining a test part, the contour of which is formed by two straight circular arcs of a circle. It is shown that when designing control, geometric criteria are used that are associated with the path of shaping, so stabilization of the cutting process is not achieved. A control design method is proposed based on the results of simulation the Material Removal Rate (MRR), which allows stabilizing the cutting process.

This paper presents a novel method of improving energy efficiency of climbing robot by implementing accumulation of motion energy and its further recycling. Patented construction and functional scheme of pedipulator – conceptual walking mechanism are provided as well as a method to integrate movement and surface attachment modules of the robot. Calculations of dynamic loads are provided followed by results of simulations that demonstrate effective approach implementation by changing kinematic or constructional parameters instead of dynamic

Background. The cutting process is carried out in a closed elastic technological machining system and is always accompanied by vibrations. Vibrations arising during cutting, depending on the amplitude, can very slightly affect the machining result, and can lead to a catastrophic loss of stability of the whole process. In any case, all researchers agree that vibration is the factor that ultimately determines the productivity of the cutting process and the quality of the machined surface.Objective. The aim of this study is to develop new technologies for selecting parameters for controlling the cutting speed to suppress chatter by passive methods, as well as to control the drive of the forming motion to suppress chatter by active methods.Methods. The goal is achieved by creating new technologies aimed at the study of dynamic processes occurring in the cutting. It is noted that the mathematical model of the cutting process should be built taking into account the loop closed of the elastic technological machining system and the function of the delayed argument, which represents machining “on the trail”. When studying the cutting process, four main groups of factors that influence its mathematical representation are taken into account, and three approaches are used to determine the stability diagram: frequency analysis, root analysis of the characteristic equation of motion of the system and the numerical method. The numerical method using the amplitude-frequency characteristics according to the corresponding stability criterion is considered to be the most effective.Results. The results of theoretical studies are used in practice in the form of technologies for passive and active chatter reduction during cutting. A technology has been developed to suppress vibrations during face milling when controlling the spindle speed according to a harmonic law. An application program for simulating a process for determining the parameters of the control law is presented. For active control, a new technology is proposed, based on the use of a CNC machine drive with an additional closed system, introducing a harmonious signal into the channel of the shaping movement, the amplitude and phase of which are automatically adjusted using the coordinate-wise descent algorithm according to the criterion of the minimum amplitude of the motor current.Conclusions. The technology of chatter suppression during face milling by controlling the spindle speed according to the harmonic law is limited by the speed of the spindle drive and its inertial characteristics. The active chatter control system uses a standard servo drive of the CNC machine, which has an additional closed loop for automatically searching for the amplitude and phase of the compensating control signal