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  • Ескіз
    Документ
    Use of analytical model for synthesis of algorithms for control of transport conveyor parameters
    (Khmelnytskyi national university, 2022) Pihnastyi, O. M.; Sobol, Maksym
    This study presents a methodology for synthesizing optimal control algorithms for the flow parameters of a conveyor-type transport system with a variable transport delay. A multi-section transport conveyor is a complex dynamic system with a variable transport delay. The transport conveyor is an important element of the production system, used to synchronize technological operations and move material. The Analytical PiKh-model of the conveyor section was used as a model for designing a control system for flow parameters. The characteristic dimensionless parameters of the conveyor section are introduced and the similarity criteria for the conveyor sections are determined. The model of a conveyor section in a dimensionless form is used to develop a methodology for synthesizing algorithms for optimal control of the flow parameters of a transport conveyor section. The dependencies between the value of the input and output material flow of the section are determined, taking into account the initial distribution of the material along the conveyor section, variable transport delay, restrictions on the specific density of the material, and restrictions on the speed of the belt. The dependencies between the value of the input and output material flow for the case of a constant transport delay are analyzed. A technique for synthesizing algorithms for optimal belt speed control based on the PiKh-model of a conveyor section is presented. As a simplification, a two-stage belt speed control is considered. Particular attention is paid to the methodology for synthesizing optimal control algorithms based on the energy management methodology (TOU-Tariffs). The criteria of control quality are introduced and problems of optimal control of flow parameters of the transport system are formulated. Taking into account differential connections and restrictions on phase variables and admissible controls, which are typical for the conveyor section, the Pontryagin function and the adjoint system of equations are written. As examples demonstrating the design of optimal control, algorithms for optimal control of the flow parameters of the transport system are synthesized and analysis of optimal controls is performed.
  • Ескіз
    Документ
    Construction of Control Systems of Flow Parameters of the Smart Conveyor using a Neural Network
    (University of Žilina, Slovakia, 2021) Sytnikova, Anastasiya; Pihnastyi, O. M.
    In this paper, the results of the model for forecasting the flow parameters of a distributed transport system of the conveyor type are briefly considered. It is shown that the model of the transport system based on the neural network can be successfully applied to predict the flow parameters of the transport system which consists of a very large number of sections.
  • Ескіз
    Публікація
    Analysis of stress in the conveyor belt (Maxwell-element model)
    (Дніпровська політехніка, 2021) Pihnastyi, O. M.; Cherniavska, S. M.
    Purpose. For a conveyor belt, the material of which corresponds to the Maxwell-element model, to analyze the causes of the occurrence of longitudinal dynamic stresses and investigate the peculiarities of the propagation of dynamic stresses along the route of material transportation. Methodology. To calculate the value of static and dynamic stresses arising in the conveyor belt, the apparatus of mathematical physics was used. Findings. A wave equation is written that determines the propagation of longitudinal vibrations in a conveyor belt, the material of which corresponds to the Maxwell-element model. An expression is obtained for calculating the speed of propagation of elastic vibrations along the conveyor belt, the frequency of vibrations and their wavelength. The characteristic relaxation time of disturbances is determined. The method of successive approximation was used to solve the wave equation. The estimation of the characteristic time of acceleration of the conveyor belt, at which there is no destruction of the material of the conveyor belt, is given. Originality. PDE-models of conveyor-type transport systems are improved, which are used to design belt speed control systems under restrictions on speed control modes. It is shown that under the modes of acceleration or deceleration of the conveyor belt, the effects associated with the occurrence and propagation of dynamic stresses along the conveyor belt, due to the characteristics of the material corresponding to the Maxwell-element model, are insignificant. Practical value. The results obtained make it possible to determine the limitations on the modes of acceleration or deceleration of the conveyor belt, preventing its damage and increased wear. This opens up prospects for designing effective control systems for the parameters of a conveyor belt, unevenly loaded with material along the transport route.
  • Ескіз
    Документ
    The information controlling model transport system during transient conditions
    (Institute of Electrical and Electronics Engineers, Inc., USA, 2019) Pihnastyi, O. M.; Kozhevnikov, G. K.; Bondarenko, Tetiana
    This article is devoted to designing an information management system for the conveyor line of mining enterprises. The analytical design method for the transient mode of the stepped speed control system of the conveyor line was developed. The partial differential equation was used in constructing the conveyor line model. The description of the production system is fulfilled in the single step approximation. A decision was obtained which determines the state of the parameters of the production line for a technological position specified as a function of time. Has been determined the length of the transition period during which the initial condition for the distribution of labour objects along the conveyor affects the parameters of the state of the conveyor line. The method for calculating the current parameters of a conveyor line with the use of partial differential equations allows the design of control systems for production lines of conveyor type for transient modes. The originality of the results obtained is to improve the PDE-models of the conveyor-type production systems used to design highly efficient production control systems operating in transient modes.
  • Ескіз
    Документ
    Neural model of conveyor type transport system
    (2020) Pihnastyi, O. M.; Khodusov, V. D.
    In this paper, a model of a transport conveyor system using a neural network is demonstrated. The analysis of the main parameters of modern conveyor systems is presented. The main models of the conveyor section, which are used for the design of control systems for flow parameters, are considered. The necessity of using neural networks in the design of conveyor transport control systems is substantiated. A review of conveyor models using a neural network is performed. The conditions of applicability of models using neural networks to describe conveyor systems are determined. A comparative analysis of the analytical model of the conveyor section and the model using the neural network is performed. The technique of forming a set of test data for the process of training a neural network is presented. The foundation for the formation of test data for learning neural network is an analytical model of the conveyor section. Using an analytical model allowed us to form a set of test data for transient dynamic modes of functioning of the transport system. The transport system is presented in the form of a directed graph without cycles. Analysis of the model using a neural network showed a high-quality relationship between the output flow for different conveyor sections of the transport system.
  • Ескіз
    Документ
    Control of the belt speed at unbalanced loading of the conveyor
    (Національний технічний університет "Дніпровська політехніка", 2019) Pihnastyi, O. M.
    Purpose. Development of algorithms for controlling the speed of the conveyor belt, based on the distributed model of the transport system, containing partial differential equations Methodology. To calculate the parameters of a conveyor line with a variable speed of material motion, an instrument of mathematical physics is used. Findings. Comparative analysis of conveyor transport system models is performed. Application of partial differential equations for simulating transport systems of conveyor type, which are complex dynamic distributed systems, is substantiated. A non-dimensional model of a conveyor system in instantaneous approximation with the use of partial-derivative equations is presented. A system of characteristic equations is recorded and a solution is developed which defines the value of material flow and material density at an arbitrary point of time for the given point of the transportation route. An expression is obtained which defines the value of material delay in the transport system depending on the velocity defect law for conveyor belt movement. Transition period time is determined during which the output material flow is defined by linear density of material disposition along the transportation route. Dependences for the material linear density and material flow for the steady state condition are defined. The performance criterion of control of flow parameters of the conveyor system is recorded and a solution of the problem of optimal control of conveyor belt speed providing the relay control mode with the minimum power consumption for material movement is found. An example of control algorithm development is given. Originality. PDE-models of transport systems of conveyor type and energy-saving algorithms for controlling such systems have been improved. Practical value. The proposed method for calculating the parameters of the conveyor line, which is a dynamic distributed system, can be used to design systems for optimal control of flow parameters of transport systems of conveyor type.
  • Ескіз
    Документ
    The optimal control problem for output material flow on conveyor belt with input accumulating bunker
    (Южно-Уральский государственный университет, 2019) Pihnastyi, O. M.; Khodusov, V. D.
    The article is devoted to the synthesis of optimal control of the conveyor belt with the accumulating input bunker. Much attention is given to the model of the conveyor belt with a constant speed of the belt. Simulation of the conveyor belt is carried out in the one-moment approximation using partial differential equations. The conveyor belt is represented as a distributed system. The used PDE-model of the conveyor belt allows determining the state of the flow parameters for a given technological position as a function of time. We consider the optimal control problem for flow parameters of the conveyor belt. The problem consists in ensuring the minimum deviation of the output material flow from a given target amount. The control is carried out by the material flow amount, which comes from the accumulating bunker into the conveyor belt input. In the synthesis of optimal control, we take into account the limitations on the size of the accumulating bunker, as well as on both max and min amounts of control. We construct optimal control of the material flow amount coming from the accumulating bunker. Also, we determine the conditions to switch control modes and estimate time period between the moments of the switching.
  • Ескіз
    Документ
    Optimal Control Problem for a Conveyor-Type Production Line
    (Springer Science+Business Media, 2018) Pihnastyi, O. M.; Khodusov, V. D.
    A method for constructing optimal control of the conveyor-type flow line parameters is developed. The model of the conveyor line is represented by the partial differential equation, which allows to take into account the distribution of products along the technological route as a function of time. Various variants of stepped speed control of the conveyor belt are investigated. The features of step control are determined. The divergence the rate of output by the flow line from the given demand for different parameters of step control is shown.
  • Ескіз
    Документ
    Calculation of the parameters of the composite conveyor line with a constant speed of movement of subjects of labour
    (National Mining University, 2018) Pihnastyi, O. M.; Khodusov, V. D.
    The development of analytical methods for calculating the parameters of a composite conveyor line using the models containing partial differential equations. To calculate the parameters of the conveyor line with a constant speed of movement of subjects of labour, the apparatus of mathematical physics is used. The solution is given in an analytic form that specifies the state parameters of the production line for a given technology's position as a function of time. The scientific novelty of the results is the improvement of PDE-models of production systems of a conveyor type. The method for calculating the parameters of conveyor production, consisting of two connecting conveyor lines with a constant speed of movement of subjects of labour is offered. The considered method of calculation of conveyor production can be extended in case of a system with an arbitrary number of connecting conveyor lines. The practical significance lies in the fact that the proposed method for calculating the parameters of conveyor production can be used to design control systems for conveyor production with an arbitrary number of conveyor lines. An essential advantage of this method is that each conveyor line is described by a single partial differential equation, the solution to which is obtained analytically. Such a representation makes it possible to use solutions for predicting the state parameters of a production line.