Центральноукраїнський науковий вісник. Технічні науки. Випуск 7. Частина 1. - 2023
Permanent URI for this collectionhttps://dspace.kntu.kr.ua/handle/123456789/13308
Browse
Search Results
Item Оцінка ергономічної стійкості транспортного потоку на дільницях дорожньої мережі. Ідентифікація математичної моделі(ЦНТУ, 2023) Войтов, В. А.; Кравцов, А. Г.; Карнаух, М. В.; Горяїнов, О. М.; Козенок, А. С.; Бабич, І. А.; Vojtov, V.; Кravtsov, А.; Karnaukh, М.; Goryayinov, О.; Kozenok, А.; Babych, І.Обґрунтовано структуру математичної моделі оцінки ергономічної стійкості транспортного потоку на різних ділянках дорожньої мережі при дії зовнішніх збурень. Математична модель враховує динаміку розвитку процесу. Крім градієнтів швидкості та щільності транспортних потоків враховуються динамічні властивості транспортних засобів та багатосмугова дорожня мережа, а також час затримок на пішохідних переходах та світлофорах. Показано, що динамічні характеристики транспортного потоку описуються диференційним рівнянням третього порядку. Отримано вирази для визначення коефіцієнтів підсилення та постійних часу, що входять у диференційне рівняння. Обґрунтовані параметри, які є вхідним впливом та визначають стійкість транспортного потоку, – це градієнти щільності та швидкості потоку. Обґрунтовані параметри, що характеризують реакцію транспортного потоку на обурення, – це постійні часу, фізичний сенс яких полягає в інерційності всіх ланок, що входять у модель. The paper discusses the structure of the mathematical model featuring assessment of the ergonomic stability of the traffic flow in various sections of the road network under the influence of external disturbances, which is the result of structural identification. The mathematical model differs from the known ones in that it takes into account the dynamics of the process development. In addition to the gradients of speed and density of traffic flows, the research takes into account the dynamic properties of vehicles and the multi-lane road network, as well as the time of delays at pedestrian crossings and traffic lights. The dynamic properties of the traffic flow are described with a third-order differential equation. The mathematical model is parametrically identified; expressions for determining the gains and time constants included in the differential equation are obtained. The input parameters impacting and affecting the stability of the traffic flow are substantiated – these are the gradients of the density and speed of the flow. The parameters characterizing the response of the traffic flow to disturbances are substantiated – these are time constants, the physical meaning of which is the inertia of all links included in the model. The study presents expressions for determining the gains and time constants included in the differential equation. The gain coefficient K1 characterizes the degree of influence of the density of the traffic flow on the reaction time of the driver. The gain coefficient K2 characterizes the influence of the degree of dynamism of the traffic flow on the time of delays during movement and loss of stability. The gain coefficient K3 characterizes the degree of influence of a change in the traffic situation on the delay time when moving in the stream and loss of stability. The value of the time constant T1 characterizes the inertia of the driver depending on the density and intensity of the traffic flow. The value of the time constant T2 characterizes the inertia of the car and is expressed in the ability to maneuver. The value of the time constant T3 characterizes the inertia of changing the traffic situation.Item Обґрунтування механізму функціонування мехатронної системи склоочищення автомобіля(ЦНТУ, 2023) Аулін, В. В.; Голуб, Д. В.; Aulin, V.; Holub, D.В статті обґрунтовано чотирьохланковий механізм мехатронної системи склоочищення автомобіля на основі аналізу параметрів закономірності руху щітки по склу і визначення можливості управління ними через мехатронні інтерфейси даної системи. Представлено математичну модель механізму склоочищення в середовищі Matlab/Simulink та проведений його кінематичний синтез. The four-link mechanism of the car's mechatronic windshield cleaning system is substantiated using different ratios of links and analysis of their kinematic and dynamic characteristics. A mathematical model of the glass cleaning mechanism in the Matlab/Simulink environment is presented and its kinematic synthesis is carried out. A mathematical model of the movement of the brush on the glass was developed for the case of close to uniform pressure distribution along the length of the brush, taking into account the unevenness of the law of movement associated with the operation of the transmission mechanism. The influence of the material properties of the rubber element on the quality of glass cleaning and the obtained values of the values characterizing the elastic and dissipative properties of the neck in the limit modes of the system are considered. The possibility of regeneration self-oscillations is shown when the dissipative properties of the neck are reduced as a result of wear or an aggressive environment. The processes of dry friction and hydraulic movement resistance occurring in the system are clarified, the limits of possible visually noticeable self-oscillations depending on the parameters of the friction mode and system operation are shown. It was found that the presence in the system of the possibility of regenerative selfoscillations in critical operating modes requires the introduction of micro-oscillations into the law of movement of the brush on the glass, which can effectively reduce the amplitudes of these self-oscillations. Analytical dependencies are proposed for calculating the parameters of the software, which implements the management of the dynamic characteristics of the system by superimposing the law of motion of microoscillations. The necessary hardware and software requirements for the controller are shown, as well as the possibility of saving the windshield wiper control unit as a functional unit of the mechatronic system for ensuring the comfort of movement.Item Удосконалення технології розбирання металоконструкцій механізованого шахтного кріплення(ЦНТУ, 2023) Боков, В. М.; Сіса, О. Ф.; Мірзак, В. Я.; Телюта, Р. В.; Пукалов, В. В.; Bokov, V.; Sisa, О.; Mirzak, V.; Teliuta, R.; Pukalov, V.Запропоновано технологію для розбирання металоконструкцій шахтного кріплення, що дозволяє замінити фізично важку та небезпечну працю оператора на більш легкий, механізований процес з використанням потужного гідравлічного біпреса. During operation, the hinge connections of mine supports practically stop rotating. This is due to the fact that, as a result of the aggressive mine water and strong dustiness, the diametrical clearance of 1-2 mm between the axis and the bushing is tightly filled with oxides and coal dust, especially in the connections of the base. This circumstance leads to the fact that the axes (pins) in the hinges lose their mobility and require significant effort for their dismantling. To repair the mechanized mine support, it is necessary to dismantle the hinge connections, which are formed by axes and holes in levers (traverses), base ears, and overlaps. Currently, the dismantling of hinge connections of mine supports is carried out using manual impact tools. This operation is extremely labor-intensive, physically heavy, and belongs to hazardous work. The goal of the study is to improve the working conditions of the operator during the dismantling process of axes in hinge connections of mine supports by using a mechanized specialized hydraulic press. To achieve the set goal, the following tasks must be solved: to determine the maximum permissible disassembly force of the axes, taking into account the strength of the load-bearing structure elements; to develop a concept of a mechanized hydraulic press, including the composition of the installation, the general technical description, the principle of operation, the kinematic scheme, and the tool. Studies have been carried out on the deformation modeling of mine support elements under load using the SOLIDWORKS Simulation calculation module to determine the maximum permissible disassembly force of the axes. It has been shown that the disassembly load of the shaft support axis with a force of more than 1000 kN leads to the loss of the structural strength reserve, which is unacceptable. An effective technology for dismantling the axes of a mechanized mine support has been proposed. A concept of an original specialized hydraulic press "Kit-100" for dismantling axes has been developed, which allows replacing the physically heavy and dangerous work of the operator with a lighter, mechanized process.