Table of contents

PREFACE

We are pleased to introduce the Proceedings of the 30th International Conference of Young Scientists and Students "Topical Problems of Mechanical Engineering 2018" (TopME 2018).

The Conference was held from November 20th to November 23rd, 2018 in Moscow, Russia. It was organized by the Blagonravov Mechanical Engineering Research Institute of the Russian Academy of Sciences (IMASH RAS). The Russian Foundation of Basic Research supported the Conference.

The scientific sections of the Conference covered a wide range of topics on materials science, strength, survivability and safety of machines, tribology, vibration processes and systems, machines mechanics and biomechanics.

List of Chairman of Program Committee, Chairman of Organizing Committee, Program Committee and Organizing Committee are available in this pdf.

All papers published in this volume of IOP Conference Series: Materials Science and Engineering have been peer reviewed through processes administered by the proceedings Editors. Reviews were conducted by expert referees to the professional and scientific standards expected of a proceedings journal published by IOP Publishing.

The aim of the present paper is to construct a mathematical model describing the impact of a rigid sphere upon a linear Kirchhoff-Love plate, made of viscoelastic auxetic with fractional viscosity. Auxetic's Poisson's ratio is a time-dependent value changing from negative to positive magnitudes with time. In the case of a linear plate, the solution out of the contact domain is found through the Green function, and within the contact zone via the modified Hertz contact theory. Integral equations for the contact force and local indentation have been obtained.

Shaping of workpieces by the methods of plastic deformation is an advanced technology of fabrication of large dimension parts. In order to optimize the process of manufacturing, the optimal conditions of plastic deformation should be chosen based on knowledge of low carbon martensitic steel specific properties. In the present paper the influence of microstructure on high temperature deformation is investigated based on experimental data for 03Cr13Ni4Mo steel.

The article discusses the deformation behaviour of T1_49.3Ni_50.7 alloy in the austenitic state during tensile tests under pulsed current and ultrasound at ambient temperature and 200 °C. The stress jumps from a combination of ultrasound and / or single pulse current are analyzed. The direction and magnitude of stress jumps are determined by the phase state of the material, the degree of deformation and the presence of electroplastic (EPE) and acoustoplastic (APE) effects. The different direction of the stress jumps in this shape memory alloy is related to the position of the deformation temperature relative to the deformation martensite formation temperature.

In this study, samples of composite wire with a matrix of aluminum alloy, reinforced with continuous carbon fibers were obtained by the method of liquid-phase infiltration with ultrasonic treatment. Mechanical tests for three-point bending were carried out and the structure of the composite was studied. The qualitative relationship between the strength of the CF/Al composite and the relief of the fracture surface is shown.

The article discusses the modeling of hydrodynamic processes in the FlowVision software package, taking into account the influence on the capillary effect of changing various parameters of a liquid, such as capillary diameter, wetting angle, surface tension force and fluid viscosity. Authors solved test tasks about the effect of the above parameters on the difference between the values obtained by mathematical methods and modeling. A qualitative and quantitative analyses of the results were made, and conclusions were drawn about the possibility of using the FlowVision software to simulate the infiltration process of the frame of reinforcing fibers with a binder when forming products from metal-matrix composites.

The article presents the study results of parameters of the macroporous composite cohesion with glass composite parameters, basalt composite and metal reinforcement elements by the pull-out of the bar from a concrete cube. It has been established that the best joint operation of reinforcement element with macroporous composite can be ensured by the use of glass composite reinforcement element. Ultimate strength of its cohesion with macroporous composite of B7.5 (D1400), B10 (D1600) classes is 20-45% higher than the values of cohesion strength of basalt composite and metal reinforcement elements for all options of combining the classes by strength and diameter of reinforcement elements (∅ 6,8,10 mm). With increased strength class of the composite, ultimate strength of all the studied types of reinforcement elements is growing consistently. The change in strength of reinforcement elements cohesion with macroporous composite through variation of their diameter has different patterns for the studied types of reinforcement elements.

The elastic properties of composites are mainly determined by the characteristics of reinforcing inclusions. This work addresses the dependence of the elastic properties of inclusion-reinforced composites on the inclusion shape. Specifically, ball-shaped, spherical and cubic inclusions are considered.

The use of string and string elements find widespread practical application in technology. In the field of measuring technology, there are many devices in which the sensitive elements are elements in the form of strings: strain gauges, accelerometers, crack meters, etc. String sensors are widely used due to its simplicity and low cost. The present paper demonstrates that preliminary studies of structural materials for the parameters of structural materials caused by a group of factors, such as surface properties, chemical composition, processing technology, can be achieved using modern methods of scanning probe, confocal, electron raster microscopy, spectroscopy, and x-ray.

The article presents the method of determining the position of the modules of surfaces that manufactured on the machine in its working space. The method is based on the use of rectangular coordinate systems of the machine working space, the module of surfaces and establishment of dimensional connections between them.

Today, when manufacturing and restoring bulk products of almost any shape and complexity degree, additive technologies are in demand, which use metal-powder compositions of various alloys as a building material. In the present work, the possibility of obtaining powder by gas atomization from batch products of high-nitrogen 04Cr20Ni6Mn11Mo2NVNb steel used for selective laser melting is shown, its structure and properties are evaluated.

The results of the study of the structure and properties of the coating based on a particulate mixture of Cu and Zn deposited by the method of cold gas-dynamic spraying are presented. The presence of diffusion during the deposition of a coating with the formation of a solid solution of copper in zinc is shown. The process of predominant diffusion of copper into zinc with a slight exposure time in the furnace with the formation of intermetallic compounds Cu5 Zn8 and CuZn, the mass fraction of which reaches 44% and 28%, respectively, is revealed. The diffusion coefficient of copper to zinc is not less than 1.56×10⁻¹³ m²·s⁻¹. An increase in the exposure time leads to a decrease in the content of beta (β ' ) and gamma (γ) phases to ≈ 15% and the formation of a solid solution of zinc in copper (α phase, 58%) with a different ratio of initial components. The formation of electronic compounds reduces the cohesive strength of the coating metal by almost two times, and an increase in the proportion of the phase leads to an increase in the cohesion above the initial value.

The analysis of extrication of stuck track vehicles methods available led to the conclusion that in case of light or moderate sticking it is justified to employ the self-extrication method using the drive wheels of the vehicle as winch heads. However, it is seldom resorted to taking into account high labor intensity and complexity of the efforts necessary to accomplish it. To exclude this drawback the authors propose a structure containing a drum with a wire wound on it that is attached to the drive wheel externally. To increase the efficiency rate and to reduce the load on the wire and the head with the wheel a fixed block is used. Essentially, this results in a winch with a tackle system whose ratio is 2. For self-extrication it is necessary to mount the mechanism on the drive wheels of the track vehicle (without removing the tracks), to fasten the blocks on fixed bearing(s), such as a stump, a tree or an anchor log, located at a distance from the vehicle, to pass the wire from the head through the block and to fasten it on the vehicle's towing shackle. The authors use the example of a 14-ton heavy vehicle to determine the main geometrical parameters of the mechanism and provide the fields of equivalent stress distribution calculated using the finite element method.

This paper addresses the operating experience of a small wind-driven power plant at Saint Petersburg Mining University. The paper describes the wind power generator operation, the deficiencies, revealed during the exploitation, as well as provides the recommendations for the plant improvement.

The article describes some aspects of strength calculation for the differential variable speed drive body of a hybrid bicycle in bodywork of Skolkovo residents' implementation of the design on the construction of hybrid bicycle for the civil and military mission.

This paper presents the methodogical approach to the assessment of geometrical and localization parameters for crack-type defects (including hidden subsurface flaws) by means mathematical treatment of experimental information represented by the amplitude displacement fields of researchable object registered by optic-interference methods.

This article is devoted to the issue of technical diagnostics in urban electric transport. To resolve the issue, it is necessary to translate the qualitative determination of the TS on some quantitative basis. The formalization of qualitative definitions is a necessary condition for the construction of formal (computable) diagnostic algorithms.

Nowadays automobile transport plays the main role nationwide. That's why transport efficiency increasing is the pressing issue of technical automobile transport operation. To assess and compare the different enterprises' operation vehicle (automobile) fleets efficiency, the production coefficients, automobile vehicles and vehicle (automobile) fleets technical readiness and other. The proposed type of expressions facilitates the calculation and relationship understanding for determining the technical readiness coefficient and determines the main factors relationship characterizing the automobile vehicles and vehicle (automobile) fleets operation efficiency.

One of the most demonstrative examples of fibrous composites application in the vehicle power structures is a spring. Fiberglass springs are not uncommon, the existing analytical design methods allow calculating its overall dimensions under the conditions of strength and stiffness, but the behavior of leaf springs with defects under load is the point of interest. At the same time, the enormously approach is extremely complicated, but modern calculation methods allow to model defects, their growth and the process of destruction, taking into account the specifics of fibrous composites. In the paper considered the process of modeling the progressive destruction of fiber reinforcement plastic (FRP) leaf spring. The here presented calculation procedure is for one-leaf spring. The features of the calculation using MSC Patran are described.

The article deals with the main points of the research on the electric motors influenced by impact and imbalance. Equipment for securing load determining the imbalance was manufactured to obtain asymmetry on the motor shaft. The results of the study on external influence on the phasechronometric profile of the asynchronous electric motors operation are obtained and processed.

The method of experimental and calculation determination of a stressed state in the NPP cases coolant input units in the conditions of rapid temperature changes is considered. A monitoring algorithm using strain gauge control and an algorithm based on solving direct and inverse problems of experimental mechanics is proposed.

The paper addresses techniques of optical compensation for rigid body displacements of objects undergoing deformation in measurement of in-plane displacements using electronic digital speckle pattern interferometry. Results of demonstration tests are presented. The proposed approaches may be useful, in particular, in study of mechanical properties of materials involving samples with stress concentrators.

Biaxial stress state obtaining in the flat tensile specimen is the main subject of this paper. Numerical simulation is the main method of investigation. All calculations were performed in ANSYS. The specimens with different geometry and location of the pairs of raisers stresses are considered. The choices of small plastic strains are shown. The interrelation of actual geometry of the specimen and the shape and size of advanced biaxial area is investigated. The experimental verification of the numerical simulation results is presented.

Simple analytical calculations of rectangular-sectioned composite console beams loaded with concentrated force, spread load or dead load are presented. The simplicity of originate expression for maximum deflections by energy methods is shown.

A computational and experimental method for determining the real hardness of the coating material and the effective (composite) hardness of the surface of engineering products hardened with hard protective coatings is developed. This method can be used to control the quality and reproduction of the technology of constructing parts with protective coatings.

A numerical calculation of a uniaxial extension of a rod is carried out in terms of the nonlocal integral theory of elasticity using the finite element method for various parameters of the material, taking into account its microstructure, and contributions of nonlocal effects. The dependencies of the strain energy are presented with increasing number of finite elements, which confirm the convergence and correctness of the mathematical model and method.

The article provides an overview of the friction surfaces microprofiling main types of the «piston-cylinder» tribounit. The calculation model is created and the program of the tribounit calculation analysis is developed. Calculations of the tribounit hydro-mechanical characteristics for different types of microgeometry are performed.

Plane problem of contact interaction for a viscoelastic foundation with multilayer coating and a rigid punch is considered. It is assumed that thin coating consists of several different elastic layers. The rigidity of the each layer depends on longitudial coordinate and can be described by own rapidly changing function. We obtain basic integral equation and additional conditions for this problem. The analytic solution of the problem is presented.

The results of studies of wear resistance and friction coefficient of polyurethane grade PT-74 filled with solid lubricant powders are presented. The abrasion patterns of the obtained polyurethanes are presented. The type and quantity of the filler providing smaller wear of a sealing element are defined. The regression analysis revealed the physical and mechanical properties of the material that have the greatest effect on wear.

Modern gas turbine bearings operate at high rotational speeds, with a speed index of up to 3· 10⁶ mmrpm. The methods currently used to calculate heat generation in aero-engine split-inner-ring ball bearings do not always give correct results, because they were developed based on tests at relatively slow speeds. To solve this problem, a number of split inner-ring ball bearings with three-point contact bearings have been tested at various levels of load, rotational speed and oil flow rate. The following bearings are tested: 126114 (d = 70 mm), 126126 (d = 130 mm) and 126130 (d = 150 mm). Tests results allowed authors to develop an empirical correlation for heat generation in split inner-ring ball bearings. Comparison with experimental data, presented in the domestic and foreign literature, shows that the coefficients in the empirical formula are selected correctly and accurately describe the thermal state of the bearing.

In the last ten years enterprises producing tyres for cars have had a tendency to the full automation that includes not only development of an independent line on tyre production, but also digital design based on the creation of a whole set of pneumatic tyres computer models with a series of calculations of their main characteristics at the car movement. Special attention is paid to the influence of the protector geometry, as well as the structure and properties of the materials of the tyre basic elements on its stress-strain state in the course of stationary rolling. To define these characteristics within the conditions of quasistatic rolling, the Abaqus program complex is used. The finite element modelling of a car tyre is carried out in the three-dimensional statement. The analysis of inflation and pressing is made both in the static state and during dynamic rolling. The results of modelling are epures of contact pressure distribution on the tyre surface.

The research paper describes a centrifugal stand and a methodology of materials testing for erosive wear in a simulative medium, which contains water, abrasive particles, and corrosive-active elements, which are analogous to the formation fluid of oil wells. There are test results in water with abrasive of four types powder materials based on iron and copper, alloyed with N1, Cr, Mo. The experiment parameters: the fluid jet speed is 11...16 ms⁻¹, the impact angle is 45°...90°, silica sand and corundum particles of different dispersion F100, F40, F24. A linear dependence of the relative wear rate on the experiment time at various impact was revealed. The wear of powder materials in liquid with corundum F100 is approximately 5 times more than with similar fraction silica. The material PK90N4MG2KD15 has the greatest erosion wear resistance under the influence of F100 fine particles.

In the work experiments on the beam of a multichannel CO₂-laser (ALTCU-3) with a unique layout within 25-130 mm using a full factorial experiment, we constructed the surface to depth and width of the zones of hardening through varying the speed of the beam in the range of 10-20 mm/s, a power of 1-2 kW and a beam diameter of 4-14 mm. Comparative wear tests showed that with the increase in the hardening area to 50% of the surface friction, the wear resistance increases by 3.2 times in comparison with the normalized steel 40Cr. It is shown that the value of the average microhardness decreases with increasing power and reducing the processing speed by 300 MPa, and the depth of the quenching zone increases up to 2.5 times.

Nonlinear force driven vibrations of thin cylindrical shells in a viscoelastic medium, the damping properties of which are described by the fractional derivative Kelvin-Voigt model, are studied. A comparative analysis has been carried out for numerical results of both free and forced shell's oscillations using two different numerical methods for the case of the combination internal resonance.

The motion of a heavy rigid body is considered, with a point (suspension point) performing high-frequency horizontal vibration. The center of mass of the body is on the principal axis of inertia for this point. Within the framework of an approximate autonomous system, pendulum-type motions of the body are studied, they occur in a vertical plane containing the axis of vibration or in a plane perpendicular to it. For a body with a mass geometry corresponding to S. V. Kovalevskaya case, a linear orbital stability analysis of these motions is performed.

This paper is dedicated to active damping of gas turbine engine blades forced vibrations using the capabilities of piezoelements. Experimental investigations are carried out with a non-rotating compressor blade, rigidly clamped on a shaker. Vibration damping was carried out by using of feedback based on a piezoelement pair fixed on the blade surface and used as a sensor and an actuator. A significant decrease of resonant stresses in the blade is shown.

In this paper, the dynamics of multi-edge trepanning vibration drilling is considered as multi-edges cutting with regenerative mechanism of oscillations excitation. The equations of new surface formation, the equations of motion for a system with one degree of freedom, and the fractional-rational cutting law are used for the numerical simulation of the dynamics of the cutting process. It presents the results of modeling the variation in chip thickness and shape of the chips.

Nonlinear forced vibrations of suspension bridges, when the frequency of an external force is approaching one of the natural frequencies of the suspension system, which, in its turn, undergoes the conditions of the one-to-one internal resonance, are investigated. The generalized method of multiple time scales is used as the method of solution. The damping features are described by the fractional derivative, which is interpreted as the fractional power of the differentiation operator. An approximate analytical solution has been obtained by the method of successive approximations.

Impact induced geometrically non-linear vibrations of a viscoelastic plate are investigated for the case when the shear operator is governed by the fractional derivative Kelvin-Voigt model in conjunction with the time-independent coefficient of volume extension-compression. Such a model could describe the behavior of so-called auxetic materials with negative Poisson's ratios. The modified method of multiple time scales involving the expansion of the fractional derivative in terms of a small parameter has been utilized for solving nonlinear governing equations of motion. The asymptotic behavior of the roots of the characteristic equation for determining the frequencies of the system as a function of the retardation time is studied and three modes of vibration in the process of impact interaction are described.

The article represents the results of mathematical modelling of behaviour of the granular medium on an oscillating rough surface. Granular medium under the action of vibration is considered as a non-Newtonian (dilatant) fluid. The system of differential equations of continuum mechanics is solved using the modified large particles method. An algorithm for solving the problem for granular media with different properties under external influences is proposed.

The probability of fan blade destruction is extremely small but not equal to zero. The consequences of fan blade-out (FBO) can be catastrophic. The absence of dangerous consequences during FBO event should be confirmed by expensive tests. This causes urgency of developing accurate computational techniques for engine structural frame vibrations analysis. In this paper, we propose an approach to determining rotor-casing system dynamic response to unbalance associated with FBO. The problem is solved in a nonlinear non-stationary formulation. Rotor-casing contact interaction, blades crown stiffness and changes in rotational speed are taken into account.

Mathematical model for the flexible rotor which has static and dynamic unbalance and enabled slip rolling on the compliant stator is developed. Also, rotation inertia, gyroscopic effect, bearings characteristics, internal hysteresis, and external viscous friction are included. The matrix approaches are used. The proposed model allows investigating the dynamic effect of total unbalance and stator displacements as an elastic and solid body on basis of the ordinary differential equations.

The article is dedicated to thermographic bench inspection of the rubber-cord pneumatic spring with or without air damper at different operating volumes. It also describes an experimental model, a procedure and results of thermographic bench tests of the rubber-cord pneumatic spring.

In the present paper, force driven vibrations of a physically nonlinear plate are studied by the method of multiple time scales when the plate is subjected to the conditions of the one-to-one internal resonance. The damping features of the surrounding medium are described by the fractional derivative Kelvin-Voight model. The influence of viscosity on the energy exchange mechanism between interacting nonlinear modes has been analyzed. For the one-to-one internal resonance, the nonlinear set of resolving equations in terms of amplitudes and phase differences has been obtained, and a comparative analysis of numerical calculations of free and forced vibrations are presented.

A model of a vibratory jaw crusher in the form of four-mass chain-type oscillating system, which oscillations are excited by self-synchronizing inertial vibration exciters installed on the working bodies is considered. Modes of the crusher motion without separating cheeks from processed medium are analyzed. Possible types of synchronization of the vibration exciters rotation and corresponding modes of the system's oscillations depending on the inertia and elasticity characteristics of the processed medium are identified.

In this paper vibrations of a thin elastic moving plate are investigated. The plate is fixed between vibrating mill rolls. Cases of cylindrical and general bending are considered. Natural frequencies and natural modes of the plate are obtained numerically. It is shown that a resonance is possible in this system under certain boundary conditions.

The three-dimensional finite element model of biomechanical system was built. The model includes the fixer, tibia bone's simulator, callus and porous scaffold. By using author's program code the bone tissue regeneration was calculated in the volume of porous scaffold with increasing external loading. The obtained results allow us to estimate the influence of mechanical loading on the process of regeneration. The presented data can be used in a clinical condition for treatment of the injured bone.

Currently, high-tech service robotics is increasingly developing. Service robots perform various tasks: patient care, condition monitoring and alert medical personnel and patient registration. In connection with the urgency of the task, this article will consider a distributed control system for mobile complexes, which task is to control, manage, and distribute tasks for complexes for the operation of re-equipping hospital wards and transporting mobile equipment in a medical institution. For more accurate route building, a local positioning system can be used. Now there are no ready-made algorithms for solving such problems. There are algorithms for managing single complexes, complexes in a closed space, and the problems of transition from the initial state to the final state have not been considered either. In this connection, a number of problems arise, which are considered in this article: transfer of medical complexes from the initial state to the final state, determination of initial parameters and conditions, determination of final parameters and conditions. During the task creation with a distributed control system, the following factors should be taken into account: the availability of the resource required for delivery on the mobile complex, the priority of the task being performed. The practical significance of the work will be determined by the result of the development of a mathematical model that will take into account all current problems and factors. As a result, a theory was determined by which the theoretical aspects were analysed and the closest toolkit of interactions within the control system in a distributed environment was selected.

Unitary operators are the basis of all calculations in quantum computers and play an important role in quantum mechanics. The presented results show that matrix forms of representation of structured DNA and RNA alphabets can be considered as a set of sparse unitary matrices. These results are useful for the development of models of quantum-algorithmic genetics, from the point of view of which living organisms are quantum-information entities.

Examples of invariants in the system of molecular genetic coding are given. Models and methods of algebraic biology based on matrix genetics (Petukhov, 2008) with the transition from matrix algebra to discrete geometry and visualization are presented. Algorithms based on genetic sub-alphabets allow displaying geometrically the biochemical composition of polynucleotide chains in spaces of different dimensions using Walsh orthogonal functions of physicochemical parameters. The visualization method makes it possible to substantiate the relationship between the parameters of DNA and RNA molecules with fractal clusters and geometric mosaics, reveals the orderliness and symmetry of polynucleotides and the noise immunity of their visual representations in the orthogonal coordinate system. A scale-parametric model of nucleic acid visualization is proposed. The developed methods can serve to simplify the perception by researchers of polynucleotide chains by visualizing them in spaces of various dimensions. Examples of visualization of the nucleotide composition of the various species of living organisms genomes are given

In two-dimensional and three-dimensional statements, a generalization of the pursuit problem is considered, when the object being pursued moves in a circle (plane case) or in a helical line (three-dimensional case), and various cases of dependence of object velocities in the problem are considered. Conditions are analytically obtained for the stability of the trajectories of motion of objects in the problem. Possible realization of this problem - the pursuit of one drone by another one as flying objects.

A method of automating the process of controlling strain gauge measurements of parameters of elastic objects using a manipulation robot is considered. The subjects of the study are elastic objects whose structure is multilayered, and individual layers have the properties of heterogeneity and nonlinearity. An example of such objects is soft biological tissue. Currently available diagnostic tools have insufficient accuracy because of the fact that the measurement results significantly affected by the errors arising from the explorer's errors during automated diagnostics and accidental interference on the part of the research object. Strain gauge measurements relate to the subject area of assessment of the state of elastic structures. The paper discusses the implementation of the algorithm for controlling the procedure of tensometric measurement of soft biological tissues, proposes engineering solutions to eliminate these drawbacks. Elimination of inaccuracies in the development of force and speed tasks causing the greatest errors achieved by using a manipulation robotics equipped with a strain gauge measurement device. A prototype of a robotic system equipped with a power sensor, a compensation mechanism and a software control algorithm is given. The results of the study are presented in the form of characteristic dependences of forces on displacements.

This paper addresses a 3DoF parallel robot. A kinematic scheme and joint types are proposed. Kinematic analysis of the mechanism is done. Aspects of robot control are considered: a power supply, a controller.

In the present work the problem of controlling the elements of a hydropneumatic suspension of a multi-axle vehicle is considered. Control algorithms are proposed that provide the required law of clearance change in various conditions. A computer simulation was carried out, which showed the correctness of the work of the presented algorithms.

The article discusses the issue of determining program forces in drives of a four-wheel robotic platform - the issue of opening the uncertainty of the equations system. The motion laws are synthesized on the basis of application of the calculus of variations. The method of determining the program forces is based on the compilation of equations of the dynamics of a rigid body motion and additional equations - "zero-functions" (displacements) of the points of the application of redundant reactions.

There is the solution of one of the problems arising in the design of mobile walking robots: the problem of achievement of minimum of energy costs at displacement of a walking robot, increasing the efficiency of a multi-legged mechanism and a reduction of the developed power due to a change in the mode of motion of the multi-legged walking apparatus.

The paper presents the rationale for the structure, the calculation of the geometric and kinematic parameters of the robot for point removal of weeds. The working area of the output link of the weeding robot was obtained, and limitations were determined to prevent its falling into the dead position.

Milling process of machining aerospace parts with cellular structure by using mirror milling system was examined. Different types of errors during machining were considered. Various techniques of reducing errors were defined.

A calculation scheme and a mathematical model of the translational motion dynamics of a solid body, simulating the movement of the underwater platform with the help of anchor-cable thrusters, are proposed. Features of motor control, DC and stepper in the structure of the actuators of the anchor-rope propulsion have been set.

This paper proposes a new method of visual automated control based on optical measurements. In this article, we investigate a number of questions concerning the organization of measurements, calibration of the data obtained, and interpretation of results. An experimental scheme is given, the coordinates of the gripper of a robotic manipulator are obtained by different methods, the accuracy is estimated. It is concluded that the use of the proposed method based on visual markers for obtaining coordinates based on visual markers has high accuracy, good repeatability of results and can be used to control the positioning of new robotic mechanisms at the testing and commissioning stage.

The article describes the method the trajectory planning of a 3-RPR robot, using the numerical solution of the forward kinematics. An algorithm for determining the position of a mobile robot platform based on the method of non-uniform coverings has been synthesized. The zones of singularity arising at some positions of the robot are investigated. The conditions for the emergence of singularity zones corresponding to its special provisions are revealed. It is shown that the solution of the forward kinematics is not unambiguous i.e. with the same change in the length of the rods there are different positions of the platform. The issues of planning the trajectory for a mobile platform are described while taking into account the zones of singularity. To implement the algorithm, a software package in the C++ language has been developed. The results of mathematical simulation are presented.

The more speeds in the automatic transmission, the better the fuel economy and the vehicle drivability. More speeds in conventional transmissions consisting only of planetary gear sets or only of gears with fixed axles lead to increase gears and shifting elements, which complicating the transmission design and growing the overall dimensions and weight. One of the ways to obtain simple transmission designs providing a great number of speeds with a relatively small number of gears and shifting elements is to use combinations of planetary gear sets and gears with fixed axles (planetary-layshaft transmissions). The main disadvantage that limits the use of planetary-layshaft transmissions is the presence of double and triple transition shifts in which 2 or 3 pairs of shifting elements are switched on and off at the same time. The problem to find out a set of speed ratios realized by the transmission with single transition shift sequences is solved in the paper on example of a planetary-layshaft transmissions consisting of two differentials and three sets of gears with fixed axles. The gear ratios magnitudes which satisfying obtained set of transmission speed ratios were found.

The objects of development were a universal loader mounted on the base of the manipulator-tripod, the algorithm and method of the "copy" control, which allows to ensure the movement of cargoes along a predetermined path.