The paper proposes a systematic approach to producing non-detachable connections which is based on unified technical solutions in the field of welding, soldering, gluing and other technologies. The given approach includes not only direct execution of the connection but its designing, preparatory operations and also measures carried out after connection producing. The proposed approach is also based on the principles of the required diversity, feedback, hierarchy and decomposition that ensures high efficiency of the developed technical solutions, possibility for setting-up and successful solution of problems in the field of producing non-detachable connections. In order to ensure a successful realization of systematic approach it is proposed to take into account a number of aspects, including the following: systematic and structural aspect that presupposes determination of internal relations and dependences between elements of the given system and it permits to obtain an overview about internal structure (composition) of the investigated system; systematic and functional aspect that presupposes determination of functions, and the system is created for performing these functions; systematic and purposeful aspect that signifies a necessity of scientific determination of system goals and sub-goals, their harmonization between themselves; systematic and resource aspect that presupposes thorough determination of the resources which are required for system performance and solution of various problems with the help of the system; systematic and integration aspect that presupposes to determine a complex of system qualitative properties which ensure its integrity and specificity; systematic and communication aspect that requires determination of external relations of the given system with others that is its relations with the environment; systematic and historical aspect that permits to determine conditions for creation of the investigated system, its past stages, modern state and also possible prospects of development. New connection designs of combined (hybrid) type have been developed on the basis of the systematic approach and the paper presents examples and classification of such connections.

Ion-plasma nitriding in glow discharge is a widely used method of surface hardening in the industrialized countries of the world and it is the most modern and technological type of surface hardening of machine parts, molds, dies and cutting tools. However there is no detailed review in the literature of technical characteristics and operation of a gas-vacuum part in ion nitriding units and it does not allow estimating electric power consumption for operation of a gas-vacuum system while assessing efficiency of the given equipment. The paper considers problems pertaining to relationship of gas-dynamic parameters of the nitriding process (pressure and gas flow rate) and energy characteristics of the glow discharge (current density, discharge voltage) during ion nitriding at industrial plants and their impact on the process. Calculation-practical modeling of a vacuum system for an ion nitriding installation shows that it is advisable to use vacuum units which represent consistently connected forevacuum and two-rotor pumps in order to ensure independent control of a pumping speed and flow rate of the gas mixture. Such approach makes it possible to carry out nitriding processes in a wide range of pressures with the possibility to provide high plasma gas rates at a low pressure, in particular, when processing large areas. The paper has revealed temperature interrelations, chamber pressure and glow discharge current density that ensure its existence in the abnormal form. It has been shown that at lower operational pressure during the process, higher degree of discharge abnormality can be provided at uniform temperature of the batch. Due to this it is possible to attain higher temperature similarity which ensures uniformity of a nitrided layer on all parts of the batch.

The paper presents results of studying structure and properties of multilayer composite coatings optimized for their composition based on zirconium dioxide materials used for deposition of plasma coatings on the models of elements for anti-meteor shielding screens. The influence of plasma jet parameters (current, distance of sputtering, consumption of plasma-forming nitrogen gas) and fractional composition of an initial powder on characteristics of two-layer composite coatings based on nickel-chromium-aluminum-yttrium and zirconium dioxide on the elements of protective screens has been analyzed in the paper. Optimization has been carried out on the basis of obtaining maximum coefficient of powder utilization. The investigations have made it possible to ascertain specific features of elemental and phase composition, surface morphology, microstructure multilayer composite coatings on the basis of a solid layer of metal oxides and a viscous transition sub-layer subjected to compression plasma flows. The investigations have been executed with the help of scanning electron microscopy, energy dispersive x-ray spectral microanalysis, and x-ray diffraction analysis. It has been shown on the basis of the obtained results that the effect of compression plasma flows on multilayer composite coatings leads to a modification of a near-surface layer with a thickness up to 15 μm that presupposes its melting and subsequent high-speed crystallization which together provide an increase in its density, decrease in porosity while maintaining the initial phase state. Liquid-phase processes in the molten phase of the near-surface layer permit to modify morphological properties of the surface which are associated with its smoothing and lowering of roughness.

The paper presents methodology for determining rational modes of abrasive processing for high-precision lenses while using a method of free lapping at finishing operations. Analytical expressions have been obtained to determine coordinates of reference points on a spherical surface which are necessary for mathematical modeling of its processing at pivotal machines. The paper contains results of a theoretical qualitative evaluation of high-precision operating lens surfaces formation in case of various combinations of setting parameters for technological equipment. In this case the most rational and unfavorable modes of processing have been identified. In particular, the last case presupposes shaping by changing rotational frequencies of an input link in an executive mechanism of the machine tool w₂and the lens w_л. An indicative feature is that a poor quality of processing has been obtained over the entire range of variation interval w₂ at maximum value w_л, and especially in the case when these frequencies are equal. It has been determined that the highest accuracy of processing is achieved with maximum amplitude of an oscillating tool motion, its diameter and frequency of part rotation and minimum rotational speed of the input link in the executive machine-tool mechanism. As such values of these setting parameters lead to an increased removal of an allowance in the marginal zone of a work-piece, then while processing a convex lens surface, its radius of curvature in each previous operation should be larger than a radius of curvature which is to be obtained in the process of subsequent operations. The inverse regularity of curvature radius values must be observed for a concave surface. The most advantageous values of the machine-tool setting parameters with various combinations have been proposed with the purpose to eliminate errors in the form of common as “knoll” and “hole” with due account of processing productivity and accuracy. The paper describes an influence of machine tool spindle wavering value on the processing accuracy of lenses having a wide range of diameters.

The paper considers algorithms for searching a maximum traffic volume of road vehicles in a traffic light cycle with a distributed intensity pulse and optimization of shifts under coordinated traffic flow control. Modeling of traffic flows have been made while using a computer program developed by the authors and it has made it possible to improve efficiency of traffic management by taking into account the distributed pulse of transport intensity. The paper proposes a model for minimizing total losses in road traffic during the integration of an incident control sub-system and route guidance for and an automatic road traffic management system as part of Minsk intelligent transportation system which has been studied as a tool for modeling a computer-aided design system "Backbone management". The model that minimizes vehicle delays, uses an algorithm implementing traffic flow intensity parameters depending on the time of day, days of the week. As a result of the simulation it has been revealed that the most effective parameter is an indicator of vehicle delays which does not always satisfy drivers trying to choose routes of their traffic which are based on a minimum transportation speed. However, from the point of view of managing an intelligent transportation system, it is necessary to choose parameters based on the requirements for minimizing delays on the road traffic network of the largest city in our country. All the proposed algorithms and models are used in the automatic traffic management system of Minsk city and will be used while creating an integrated intellectual transportation system of the city.

Transient modes of bridge cranes movement determine their energy, dynamic and electrical performance, as well as productivity and durability of work. An optimal control problem of its movement has been solved while making an analysis of indicators for efficient performance of a bridge crane. Terminal and integral criteria have been selected as optimization criteria. They represent undesirable dynamic properties of the crane. Legendre method has been used to determine the possibility for achieving minimum of the optimization criterion. An analysis of the Euler-Poisson equation, which is a necessary condition for the minimum of the integral criterion, has shown that it is impossible to find a solution for the optimization problem in an analytical form. A method of differential evolution has been used in order to find an approximate solution to the optimization problem. The approximate (suboptimal) solution has been found in the complex domain, which is a limited domain conjunction of dynamic parameters and phase coordinates of the system. Limitation in the domain of the system phase coordinates (a polynomial basis function has been used in the paper) provides the possibility to attain absolute minimums of terminal problem criteria. A simulation of the bridge crane motion has been carried out in order to establish an efficiency for implementation of the suboptimal control. During this process dynamic mechanical characteristics of its electric drive have been taken into account. While carrying out the simulation, a frequency and an amplitude of the electric drive voltage in the crane movement mechanism have been changed (frequency scalar method for speed changing of an asynchronous electric drive has been used). A comparative analysis of the dynamic, kinematic, electrical and energy performance indicators of the bridge crane under suboptimal and S-curved (standard) laws of frequency and voltage variations in the crane electric drive has made it possible to establish an improvement in the efficiency of its operation under suboptimal control.

The paper presents description of a mechatronic control system for mechanical transmission of a 20-ton truck, as well as its adaptive start-up algorithm, transient process behavior which significantly affects durability of automated power unit elements, vehicle movement smoothness and driver’s comfort when driving. A multidisciplinary model of the mechatronic control system has been developed in the software package Imagine Lab AMESim because its power unit including a diesel engine, a dry frictional two-disc clutch, a main mechanical stepped gearbox and an additional gearbox has electrical components besides mechanical and pneumatic ones. The given model allows to test complex control algorithms and analyze the behavior of intelligent systems in the early designing stages. The research has been carried out on the basis of the test complex at Department “Automobiles”, Automotive and Tractor Faculty, Belarusian National Technical University. Research results confirm an adequacy of the AMESim developed multidisciplinary model. Feedback on the increment of an angular velocity difference between driving and driven parts of the friction clutch has been introduced for precise friction clutch control. Threshold values of a feedback parameter have been determined on the basis of the developed computer model and these values will be used for programming a microprocessor unit when implementing an adaptive algorithm for a truck start-up process

The world industry is on a threshold of a new development cycle which is characterized by emergence of breakthrough technologies: distributed ledger technology, drone-type devices, 3D printing, virtual reality, Internet of things, augmented reality etc. Due to these technologies fundamental changes will take place in the majority of economic branches. The automotive industry is not an exception. This industry plays one of the key roles in economy in a great number of countries and changes occurring in it lead not only to creation of new products, technical processes but these changes also entail improvement of the industrial base which has been already created. The Republic of Belarus considers an automotive industry as one of key industries for its economy and its efficiency has a high dependency factor pertaining to speed of innovation emergence and implementation that is strategically important aspect of increase in competitiveness both on current sales markets and on potential ones. The paper pays a special attention to two main trends arising in the course of forming a new industrialization: increase in environmentally-friendly fuel systems and digital transformation. Problems of world ecology have exerted a considerable impact on developments in the field of alternative energy sources. Speed of development and promotion of electric vehicles considerably exceed “breakthrough” innovation developments of the past. However a great number of factors can have a significant effect on the future of electric vehicles and two of them are thoroughly considered in the paper: cost of energy (batteries) and price of oil (at the price of about 20 USD for barrel the development rate will considerably decrease). Besides the matter of environmental friendliness the paper pays attention to services of digital transformation. The world has already presented examples pertaining to usage of remote control for dump trucks, telematics etc. Such an approach makes it possible for organizations to optimize substantially an expenditure budget and doing so we increase resource use efficiency. The paper also contains a review of innovations in the automotive industry of the Republic of Belarus: BelGee electric cars, Belkommunmash electrobuses, developments of large industrial equipment.

The paper deals with a workflow of a proportional pressure modulator equipped with a linear electric motor of electromagnetic type (LEMET). A schematic diagram consisting of a power supply and control system has been constructed to determine the performance of LEMET. The power supply system is a self-contained half-bridge inverter. The converter input is supplied with 12 V DC voltage. The motor phase is powered by an inverter which includes transistor switches and diodes. The control system of the autonomous inverter consists of two channels – a current limiting channel and a linear transfer channel. The study is based on the results of numerical and simulation modeling of LEMET workflows. Numerical simulation is performed and investigated by a finite element method in the FEMM environment. Geometry of the LEMET model lies in the region of air with an electromagnetic permeability of 1. An initial radius of the grid generation for the working gap area is 0.5 mm, while for other areas an adaptive generation method has been applied. In order to determine a continuous power function at any point within a current variation interval i and a displacement x current linkage and electromagnetic force functions have been approximated by polynomials use of the Curve Fitting application. The simulation LEMET model of a proportional modulator has been built in the MatLab Simulink environment. The implicit Runge-Kutta method using the secondorder inverse differentiation formulas with a variable step has been applied for solution of a mathematical model in the MatLab Simulink system. The equation of an electrical circuit for an inductor motor phase has been compiled according to the second law of Kirchhoff. The LEMET traction characteristics have been obtained by moving a locking and adjusting element (LCE) from 0 to 6 mm in steps of 1 mm while changing the MMF in the winding from 0 to 2 A in steps of 0.1 A. It has been established that in order to move the LCE by 6 mm with the speed of 40 mm/s with a resolution of 0.15 mm, the maximum value of the current in the LEMET winding is equal to 2.5 A. In this case the value of the electromagnetic force is 120 N. This makes it possible to improve an accuracy of the brake drive pressure regulation by 12.3 %. Solutions have been proposed to increase the LEMET speedwork. Characteristics of the engine have been described and numerical parameters of LEMET have been determined in the paper. The developed simulation model allows to investigate functional properties and dynamic characteristics of the proportional modulator with a relative error of 4.07 %.