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Статті в журналах з теми "Hydraulic drive system"

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Ivanov, Konstantin Samson, and Baurjan Tultayev. "Adaptive Hydraulic Drive of Manipulator." Applied Mechanics and Materials 841 (June 2016): 215–20. http://dx.doi.org/10.4028/www.scientific.net/amm.841.215.

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Анотація:
At present in manipulators the hydraulic drives with one degree of freedom are used. Such drive provides single-valued function of constraint between input and output links motion. However for overcoming of variable force of resistance it is necessary to use the variable transfer ratio between input and output links. The adjustable drive should contain the controlled gear box. Such drive contradicts the demand of minimization of weight and sizes of modules of the manipulator. Use of electronic control systems for force regulating leads to extreme complication of drives, decrease in their reliability, raise of cost of manufacturing and maintenance.Recently the adaptive self-controlled mechanical systems were appeared. By analogy to the adaptive mechanism the hydraulic adaptive mechanism which provides force self-regulation without a control system has been developed and the patent for invention was received.In paper the description and research of the adaptive hydraulic mechanism and creation of the manipulator module with the simplest compact hydraulic drive are adduced.
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INOGUCHI, Rikiya, Kazuhisa ITO, and Shigeru IKEO. "Pure-Hydraulic Hybrid Cylinder Drive System with Hydraulic Transformer." JFPS International Journal of Fluid Power System 5, no. 1 (2012): 1–5. http://dx.doi.org/10.5739/jfpsij.5.1.

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Wang, Hua Bing, and Jun Ke Hu. "Durability Testing System with Power Recycle for the Variable Displacement Closed-Loop Hydraulic Pumps." Applied Mechanics and Materials 241-244 (December 2012): 1333–37. http://dx.doi.org/10.4028/www.scientific.net/amm.241-244.1333.

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Анотація:
A testing system scheme with power recycle for hydraulic pumps’ durability is present, which is based on a hydraulic motor with hydraulicly overridden pressure compensation. The hydraulic motor can adaptively adjust its displacement to meet the demand of displacement match of the power feedback in the system. The system pressure can be set by adjusting the starting control pressure of the motor. The rotating speed of the pump is guaranteed by the control of the driven electrical motor. A hydraulic bridge unit is used to guide the flow from the outport of the pump to the fixed inlet port of the hydraulic motor and thus causes the motor to rotate in a certain direction to drive the pump in order to recycle the power.
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KOSUGI, Akira, Mizuho NAKAMURA, Shigenobu SUZUKI, Masanobu CHIBA, and Keigo HARA. "Research on Interlock System in Hydraulic drive system." Proceedings of Mechanical Engineering Congress, Japan 2016 (2016): G1700203. http://dx.doi.org/10.1299/jsmemecj.2016.g1700203.

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Xu, Ming, Xiao-meng Wu, Xin Yu, and Guo-jin Chen. "Dynamic performance of auxiliary hydraulic power unit based electro-hydraulic variable speed drive system." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 232, no. 16 (August 24, 2017): 2926–36. http://dx.doi.org/10.1177/0954406217727770.

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Анотація:
Inability of dynamic performances, especially the acceleration response, strongly inhibits the application of electro-hydraulic variable speed drive, even though its intrinsic energy-saving potential. In contrast to variable speed drive, the valve-controlled actuator system shows the capacity of fast response and accurate control precision, but it consumes more energy. The controllable auxiliary power unit based electro-hydraulic variable speed drive system is probably a solution to enhance dynamic performance of variable speed drive on the basis of energy-saving. Except for the principal variable speed power source, there is an auxiliary power source—auxiliary power unit, which is actually a semi-active hydraulic accumulator unit. The auxiliary power unit can detect the relation between the supplied power by power source and the demanded power by actuator, and then release or absorb hydraulic power to improve actuator dynamic response. The dynamic performance of auxiliary power unit based variable speed drive system was investigated experimentally. Firstly, the set-up of proposed drive system was introduced. Dedicated to the complicated characteristics of multi-input-multi-output and strongly nonlinearity, the mathematical model was deduced, and a hierarchical control strategy was illustrated. The experimental results under two typical variable-load conditions were discussed. Furthermore, the comparisons were explained with the other three drive systems, which were valve-controlled motor drive, conventional variable speed drive, and pump-valve compound drive. Based on the experimental results, it is concluded that the auxiliary power unit based variable speed drive demonstrates an excellent dynamic performance, which can significantly improve the actuator response and control precision, as well as obtain a good energy-saving behavior.
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Devisilov, V., and E. Sharai. "Hydrodynamic filters in hydraulic fluid cleaning system of hydraulic drive." IOP Conference Series: Materials Science and Engineering 492 (March 13, 2019): 012025. http://dx.doi.org/10.1088/1757-899x/492/1/012025.

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Cao, You Hui, Jin Liu, Li Fu Shao, Fei Liu, and Wen Qun Xu. "Intelligent Driver Designing for Electro-Hydraulic Proportional Valve of Engineering Machine." Advanced Materials Research 562-564 (August 2012): 1108–12. http://dx.doi.org/10.4028/www.scientific.net/amr.562-564.1108.

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Intelligent driver based on C8051F500 and TLE7242-2G for electro-hydraulic proportional valve was designed in this paper. The driver has CAN interface, and can drive four channel electro-hydraulic proportional valves. The system scheme, power unit, MCU unit, drive unit and software were analyzed in detail. At last the system performance was simulated with MATLAB. The Intelligent driver is suit for modern engineering machine’s control system, which demands networking and distributed control.
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Rutkevych, Volodymyr. "INVESTIGATION OF TRANSITIONAL PROCESSES IN THE ADAPTIVE SYSTEM OF HYDRAULIC DRIVES OF THE MECHANISM FOR CUTTING AND UNLOADING STALK FODDER." Vibrations in engineering and technology, no. 2(101) (June 29, 2021): 107–14. http://dx.doi.org/10.37128/2306-8744-2021-2-12.

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The problem of creating an energy-efficient and competitive mechanism for cutting and unloading stalk fodder from trench storage, by developing and justifying the parameters and modes of operation of the adaptive system of hydraulic drives of the mechanism is researched. The principal implementation of the adaptive system of hydraulic drive of the mechanism for cutting and unloading is proposed, in which a spool flow divider is placed between two executive hydraulic motors, which allows to regulate the supply of a U–shaped frame according to the load change which affects the cutting mechanism. The adaptive system of the hydraulic drive of the mechanism allows to stabilize energy consumption for separation of a portion of a stalk fodder under the condition of change and fluctuation of parameters which essentially influence the process of separation and unloading of a stalk fodder from the monolith. The transients in the adaptive systems of hydraulic drives of the mechanism for cutting and unloading of stalk fodder are received and analyzed. As a result of the study, it was found that by changing the operating widths of the slide valve of the separator in the direction of reduction, a significant increase in the responsiveness of the hydraulic drive system of the mechanism for cutting and unloading to the changes in the loading on the cutting apparatus. As a result, the range of the adjustment of the feeding of the hydraulic cylinder of the U–shaped frame, which increases the efficiency of stabilizing the separation process from the monolith of block-portion of stalk fodder with a minimum power of the hydraulic drive system, is substantially expanded. It is noted that the dynamic characteristics of the hydraulic drive of the mechanism for cutting and unloading stalk fodder adaptive to the load are influenced by the design parameters of the spool flow divider which implements feedback. On the basis of the conducted experimental research recommendations on the choice of constructive parameters of the spool flow divider are given.
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Khristoforov, Evgeniy, Nataliya Sakovich, and Aleksandr Kuznecov. "SAFETY SUPPORT IN TRANSPORT CONSTRUCTION MACHINERY WITH HYDRAULIC DRIVE." Bulletin of Bryansk state technical university 2021, no. 7 (June 16, 2021): 38–49. http://dx.doi.org/10.30987/1999-8775-2021-7-38-49.

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Work purpose: the investigation of transport process safety in construction industry of the Bryansk region, the substantiation of reasons, factors and circumstances of accidents in the construction companies of the region, the substantiation of the impact of hydraulic drive unit failures upon safety of transport construction machinery with the hydraulic drive with the purpose of driver safety. Investigation problem: on the basis of the obtained results of the safety investigations of transport processes, reasons defined, revealed injury factors of drivers during the operation of the load flat car hydraulic drive of transport means to develop motion parameters of the “hydraulic drive-load flat car” system which will not allow arising oscillations of the system resulting in hydraulic drive failure arising which has influence upon driver’s work safety. The investigations were carried out on the basis of a system analysis of accident examinations in the regional construction industry which on the basis of statistical data allows the defining safety state of transport construction machinery. By means of investigations it is defined that 90% of transport construction machines are equipped with a hydraulic drive. In the hydraulic drive the most significant element is a hydraulic cylinder – the most loaded element performing all basic operations of a working process of loading and unloading. In the hydraulic drive there is used a telescopic hydraulic cylinder in which during operation there are revealed design-production defects (DPD) which result in injury of machine service personnel. One of DPD manifestations is oscillation formation in the hydraulic drive which results in the destruction of hydraulic cylinder attachment fitting. It is defined that the support of hydraulic drive reliability and safety is a difficult problem which needs a complex solution still at designing and creation, and during the operation. The complexity of the problem causes the necessity of design and operation parameter optimization, in the first place, that of an executing hydraulic cylinder of the hydraulic drive with the use of mathematical modeling. The review of the mathematical modeling methods of hydraulic cylinder parameters allows drawing the conclusion that the existing methods have many assumptions and do not allow creating completely reliable and safe transport construction engineering. The investigation novelty consists in the offered procedure for the solution of motion equations of the “hydraulic drive – load flat car” system which allows calculating the motion system parameters, defining the development of system oscillation above critical able to destruct a fitting unit of the hydraulic cylinder to the load flat car. Conclusion. The algorithm offered for the solution of mathematical equations allows making a conclusion on the stability and safety of the “hydraulic cylinder – load flat car” system, finding optimum values of motion parameters at any time moment of a transitional process.
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Popov, A. Y. U. "Simulation modeling of the volumetric hydraulic drive." Traktory i sel hozmashiny 85, no. 3 (June 15, 2018): 45–53. http://dx.doi.org/10.17816/0321-4443-66397.

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Анотація:
In the design of a variety of the modern agricultural machines, the hydraulic drive with reciprocating motion for lifting, lowering and moving the working bodies has obtained a wide application. One of the important stages in the design of hydraulic drives and transmissions is a simulation. In connection with the laboriousness of carrying out the full-scale experiment and the cumbersome calculation of mathematical models of hydrosystems, as well as the development of the computing machinery, the simulation modeling has obtained a widespread usage. This type of computer simulation allows to investigate complex systems based on the development of multilink factor models with the visualization of a numerical experiment. The article presents the procedure for the simulation modeling of dynamic processes occurring in the volumetric hydraulic drive. The model is developed on the basis of standard libraries of the computing system MATLAB Simulink. The volumetric hydraulic drive is presented in the form of a structural model and consists of interconnected blocks that on the base of differential equations modeling the operation of a pumping station with a mechanical drive, a safety valve, a three-section four-line hydraulic distributor, double-acting power cylinder with special rod, a hydraulic tank. During the calculation of the simulation model takes into account a change of the modulus of elasticity of the fluid depending on the pressure in the hydraulic system, the parameters of the working fluid, the stiff stop when the extreme positions are reached by the rod of the hydraulic cylinder, the friction between the moving parts in the power hydrocylinder. The developed program allows to simulate working processes at the design stage and obtain the necessary data on the dynamic properties of the hydraulic system in all modes of operation, to demonstrate in the form of graphs and oscillograms, to simplify the analysis of transient processes in the hydraulic system, and also to select the rational design parameters of constituent elements of the volumetric hydraulic drive.
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Дисертації з теми "Hydraulic drive system"

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Lodewyks, Johann, and Pascal Zurbrügg. "Decentralized energy-saving hydraulic concepts for mobile working machines." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-199996.

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Анотація:
The high price of batteries in working machines with electric drives offer a potential for investment in energy-saving hydraulic systems. The decentralized power network opens up new approaches for hydraulic- and hybrid circuits. In addition, the regeneration of energy can be used at any point of the machine. For the example of an excavator arm drive with a double cylinder two compact hydraulic circuits are presented, which relieve a central hydraulic system.
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Sagström, Johan. "Streamlined LCA model and complete assessment of a hydraulic drive system." Thesis, KTH, Skolan för industriell teknik och management (ITM), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-217801.

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This master thesis was commissioned by Bosch Rexroth AB and carried out over the course of 20 weeks between January and May 2017. The company produces hydraulic drive systems for different industrial applications, mostly for rotating heavy loads under constant, low speed and high torque. The products have a long life span and thus, optimizing the design of their products can have a considerable impact in terms of energy efficiency and environmental performance. In order to gain a better understanding of what role individual parts of the system have in terms of sustainability and to further investigate the entire life-cycles and environmental footprints of their products, Bosch Rexroth looked to the Life Cycle Assessment (LCA) method. There were two different major aims to this thesis project. The first aim was to provide Bosch Rexroth with in-depth knowledge around how their product systems perform from an environmental point of view, and more specifically one particular hydraulic drive. The second aim was to develop a tool tailor-made for Bosch Rexroth, capable of delivering simplified LCAs in a quick and easy fashion. The purpose of the tool was to assist Bosch Rexroth in decisionmaking during product development. In addition, the simplified tool should come with an interface easy to understand and use. The study was done according to a life cycle assessment approach and followed applicable international standards ISO 14040 and 14044. The LCA was simulated in the SimaPro 8 software, which was also used for all calculations including impact assessment according to the ReCiPe methodology. The results of the LCA were considered stable and representative for a specific case study of a hydraulic drive in operation at a paper mill in Sweden. The results from the simplified LCA model were considered satisfactory and within desired tolerance. One of the key conclusions of the thesis was a take-back system for some of the parts of the hydraulic drive could benefit the environment to a large extent, which should encourage Bosch Rexroth to examine such possibilities further.
Detta examensarbete genomfördes på uppdrag av Bosch Rexroth AB under 20 veckor mellan januari och maj 2017. Företaget producerar hydrauliska drivsystem för många olika industriella applikationer, främst för att rotera tunga laster under konstant, låg hastighet och högt vridmoment. Produkterna har en lång livslängd vilket innebär att optimering av designen kan ha en betydande inverkan på energieffektivitet och miljöprestanda. Detta examensarbete utfördes i syfte att ge Bosch Rexroth en bättre förståelse för vilken roll enskilda delar av systemet har när det gäller miljöpåverkan. Projektet hade två huvudmål. Det första målet var att ge Bosch Rexroth en djupare kunskap om hur deras produktsystem påverkar miljön, och mer specifikt en särskild hydraulisk motor. Det andra målet var att utveckla ett verktyg som var skräddarsytt för Bosch Rexroth och som kunde leverera förenklade livscykelanalyser på ett snabbare och enklare sätt än den som avhandlas i denna rapport. Dessa förenklade analyser skulle sedan kunna användas som beslutsunderlag i anknytning till produktutveckling. Utöver det skulle det skräddarsydda verktyget ha ett grafiskt gränssnitt som skulle vara lätt att förstå och använda. Livscykelanalysen gjordes enligt gällande internationella standarder ISO 14040 och 14044. Analysen simulerades i mjukvaran SimaPro 8, som också användes för alla påverkansberäkningar och konsekvensbedömning enligt ReCiPe-metoden. Resultaten ansågs stabila med avseende på den genomförda fallstudien av en motor i drift vid ett pappersbruk i Sverige. Resultaten från den förenklad LCA-modellen betraktades som tillfredsställande och inom den önskade toleransen. En av de viktigaste slutsatserna av arbetet var att ett strukturerat återanvändningssystem för vissa av detaljerna i motorerna skulle kunna ge en potentiellt mycket fördelaktig miljömässig påverkansförbättring. Bosch Rexroth uppmuntras därför att vidare undersöka möjligheterna med ett sådant system, både i Sverige och på de globala marknaderna.
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Shimizu, Juri, Takuya Otani, Kenji Hashimoto, and Atsuo Takanishi. "Simulation of an interlocking hydraulic direct-drive system for a biped walking robot." Technische Universität Dresden, 2020. https://tud.qucosa.de/id/qucosa%3A71091.

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Biped robots with serial links driven by an electric motor experience problems because the motor and transmission are installed in each joint, causing the legs to become very heavy. Previous solutions involved robots using servo valves, a type of highly responsive proportional valve. However, high supply pressure is necessary to realize high responsiveness and the resulting energy losses are large. To address this problem, we proposed a hydraulic direct-drive system in which the pump controls the cylinder meter-in flow, while a proportional valve controls the meter-out flow. Furthermore, our hydraulic interlocking drive system connects two hydraulic direct-drive systems for biped humanoid robots and concentrates the pump output on one side cylinder. The meter-in flow rate of the other side cylinder is controlled by the meter-out flow rate of the cylinder on which the pump is concentrated. A comparison of the walking simulation performance with that of the conventional independent system shows that our proposed system reduces the motor output power by 24.3%. These results prove the feasibility of constructing a two-legged robot without having to incorporate highly responsive servo valves.
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Fernandes, Rita. "Efficient Volvo Bus Cooling System,Using Electrical Fans : A comparison between hydraulic and electrical fans." Thesis, KTH, Kraft- och värmeteknologi, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-155901.

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Economical and environmental factors together with energy policies towards more efficient systemsare the driving force for the development of the vehicle industry. Significant changes have beenmade to fulfill new emissions legislation but the basic internal combustion vehicle architecture hasbeen kept. New emission treatment systems that increase the thermal loading of the cooling systemhad been added within the same package envelope as before, which means less space to place coolingfans and a greater need for airflow. Changes in the cooling system, namely the replacement of thehydraulic fan drive system by electrical fans is one of the energy efficient alternatives for severalcity buses under certain environments, like the ”typical red city buses”, well-known in the UnitedKingdom. In this thesis study, hydraulic fans are compared with electrical fans and a road-mapof the benefits and drawbacks of the two systems is developed, based on real traffic performanceperformance data and the results of existing simulations and tests. In addition, new simulations arepresented in order to find the most efficient design for the cooling system as well as a comparisonof these results with previous ones. This road map will be used later by Volvo-Buses Group as atool to better understand in which circumstances electrical fans can be beneficial, in terms of fuelconsumption, noise production, cooling performance, control of the fans and associated costs.
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Lammers, Zachary A. "Thermal Management of Electromechanical Actuation System for Aircraft Primary Flight Control Surfaces." University of Dayton / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1399021324.

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Бурлига, Михайло Борисович. "Розвиток методів розрахунку та вибір раціональних схем двопотокових безступінчастих гідрооб'ємно-механічних трансмісій колісних тракторів". Thesis, НТУ "ХПІ", 2017. http://repository.kpi.kharkov.ua/handle/KhPI-Press/35538.

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Дисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю 05.22.02 – автомобілі та трактори. Національний технічний університет "Харківський політехнічний інститут", Харків, 2017. Дисертація присвячена розвитку методів розрахунку для аналізу робочих параметрів безступінчастих ГОМТ і їх основних елементів ГОП, прогнозуванню техніко-економічних показників машинно-тракторного агрегату для визначення раціональних схемних рішень ГОМТ. Актуальність роботи полягає у необхідності забезпечення конкурентоспроможності вітчизняних тракторів. Здійснено аналіз роботи двопотокових ГОМТ колісних тракторів зарубіжних аналогів. Уточнено на підставі новітніх експериментальних даних щодо втрат і ККД математичну модель об’ємних аксіально-поршневих гідромашин, як основних елементів тракторних ГОМТ. Розроблено алгоритм і обчислювальну процедуру щодо встановлення взаємно однозначної відповідності між робочими параметрами, втратами і ККД ГОП в прямому і зворотному потоках потужності крізь ГОП під час їх роботи у складі двопотокових ГОМТ. Вперше розроблено розрахунково-теоретичну методику і програмну реалізацію з визначення параметрів ГОП, ГОМТ і основних техніко-економічних показників МТА з урахуванням режимів циркуляції потужності, втрат в ГОП, ГОМТ і буксування трактора для аналізу і прогнозування характеристик альтернативних тракторних ГОМТ та наукового обґрунтування найраціональнішої трансмісії для конкретного трактора. Вперше вирішено задачу побудови універсальних характеристик тракторів з ГОМТ і візуалізації робочих параметрів ГОМТ у всьому діапазоні експлуатаційних режимів трактора для порівняння альтернативних схемних рішень ГОМТ і вибору найраціональнішого з них. Побудовано універсальні характеристики першого в Україні трактора ХТЗ-21021 з ГОМТ-1С розробки НТУ "ХПІ" і АТ "ХТЗ". За результатами чисельного і натурного експериментів зроблено висновок, що математичні моделі й запропоновані методики є адекватними і спрямованими на підвищення ефективності та конкурентоспроможності вітчизняних тракторів.
Thesis for Scientific degree of candidate of technical sciences, specialty 05.22.02 – vehicles and tractors. National Technical University "Kharkiv Polytechnic Institute", Kharkiv, 2017. The work is devoted to solving the technical problem of development of calculation methods and choice of rational schemes of dual path hydraulic volume mechanical transmission (HVMT) wheeled tractors, which allows you to select the optimal scheme HVMT at the design stage. Actuality of work consists in the necessity of providing of competitiveness of Ukraine tractors. The analysis of work of the dual path HVMT tractors of foreign analogues is carried out. Refined mathematical model of hydrostatic axial-piston hydraulic machines as the main HVMT elements identity-based loss coefficients with the latest experimental data loss and coefficient of performance (COP). The algorithm and the computational procedure for the establishment of a oneto-one correspondence between the operating parameters and the efficiency of hydraulic drive system (HDS) losses in forward and reverse flow of power through the HDS for her work in the dual path tractor HVMT. Calculation-theoretical methodology and her programmatic realization is first worked out for determination of HDS parameters, dual path HVMT and basic technical and economic indexes of tractor-aggregate taking into account the modes of circulation of power, losses in HDS, HVMT and skidding of tractor for an analysis and prognostication of descriptions alternative tractor HVMT and scientific ground of the most rational transmission for a certain tractor. The problem of construction of universal descriptions of tractor is first set and decided with dual path HVMT. Original solution of task offers on visualization of kinematics, power and power parameters of dual path HVMT of the perspective Ukrainian tractors in all range of their operating modes as an important criterion for comparison of alternative schematics of HVMT. Universal descriptions of first in Ukraine and on post-soviet space of tractor of XTZ-21021 from stepless HVMT-1S development of NТU "KhPI" and propulsion MODULE of "XTZ" are built. Results numeral and natural experiments allow to draw conclusion, that the calculation-theoretical methodologies and constituents of them worked out in dissertation mathematical models are adequate and directed to on an increase efficiency and competitiveness of the Ukrainian tractors.
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Бурлига, Михайло Борисович. "Розвиток методів розрахунку та вибір раціональних схем двопотокових безступінчастих гідрооб'ємно-механічних трансмісій колісних тракторів". Thesis, НТУ "ХПІ", 2018. http://repository.kpi.kharkov.ua/handle/KhPI-Press/35536.

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Дисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю 05.22.02 – автомобілі та трактори. Національний технічний університет "Харківський політехнічний інститут", Харків, 2017. Дисертація присвячена розвитку методів розрахунку для аналізу робочих параметрів безступінчастих ГОМТ і їх основних елементів ГОП, прогнозуванню техніко-економічних показників машинно-тракторного агрегату для визначення раціональних схемних рішень ГОМТ. Актуальність роботи полягає у необхідності забезпечення конкурентоспроможності вітчизняних тракторів. Здійснено аналіз роботи двопотокових ГОМТ колісних тракторів зарубіжних аналогів. Уточнено на підставі новітніх експериментальних даних щодо втрат і ККД математичну модель об’ємних аксіально-поршневих гідромашин, як основних елементів тракторних ГОМТ. Розроблено алгоритм і обчислювальну процедуру щодо встановлення взаємно однозначної відповідності між робочими параметрами, втратами і ККД ГОП в прямому і зворотному потоках потужності крізь ГОП під час їх роботи у складі двопотокових ГОМТ. Вперше розроблено розрахунково-теоретичну методику і програмну реалізацію з визначення параметрів ГОП, ГОМТ і основних техніко-економічних показників МТА з урахуванням режимів циркуляції потужності, втрат в ГОП, ГОМТ і буксування трактора для аналізу і прогнозування характеристик альтернативних тракторних ГОМТ та наукового обґрунтування найраціональнішої трансмісії для конкретного трактора. Вперше вирішено задачу побудови універсальних характеристик тракторів з ГОМТ і візуалізації робочих параметрів ГОМТ у всьому діапазоні експлуатаційних режимів трактора для порівняння альтернативних схемних рішень ГОМТ і вибору найраціональнішого з них. Побудовано універсальні характеристики першого в Україні трактора ХТЗ-21021 з ГОМТ-1С розробки НТУ "ХПІ" і АТ "ХТЗ". За результатами чисельного і натурного експериментів зроблено висновок, що математичні моделі й запропоновані методики є адекватними і спрямованими на підвищення ефективності та конкурентоспроможності вітчизняних тракторів.
Thesis for Scientific degree of candidate of technical sciences, specialty 05.22.02 – vehicles and tractors. National Technical University "Kharkiv Polytechnic Institute", Kharkiv, 2017. The work is devoted to solving the technical problem of development of calculation methods and choice of rational schemes of dual path hydraulic volume mechanical transmission (HVMT) wheeled tractors, which allows you to select the optimal scheme HVMT at the design stage. Actuality of work consists in the necessity of providing of competitiveness of Ukraine tractors. The analysis of work of the dual path HVMT tractors of foreign analogues is carried out. Refined mathematical model of hydrostatic axial-piston hydraulic machines as the main HVMT elements identity-based loss coefficients with the latest experimental data loss and coefficient of performance (COP). The algorithm and the computational procedure for the establishment of a oneto-one correspondence between the operating parameters and the efficiency of hydraulic drive system (HDS) losses in forward and reverse flow of power through the HDS for her work in the dual path tractor HVMT. Calculation-theoretical methodology and her programmatic realization is first worked out for determination of HDS parameters, dual path HVMT and basic technical and economic indexes of tractor-aggregate taking into account the modes of circulation of power, losses in HDS, HVMT and skidding of tractor for an analysis and prognostication of descriptions alternative tractor HVMT and scientific ground of the most rational transmission for a certain tractor. The problem of construction of universal descriptions of tractor is first set and decided with dual path HVMT. Original solution of task offers on visualization of kinematics, power and power parameters of dual path HVMT of the perspective Ukrainian tractors in all range of their operating modes as an important criterion for comparison of alternative schematics of HVMT. Universal descriptions of first in Ukraine and on post-soviet space of tractor of XTZ-21021 from stepless HVMT-1S development of NТU "KhPI" and propulsion MODULE of "XTZ" are built. Results numeral and natural experiments allow to draw conclusion, that the calculation-theoretical methodologies and constituents of them worked out in dissertation mathematical models are adequate and directed to on an increase efficiency and competitiveness of the Ukrainian tractors.
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Pokorný, Jan. "Interakce mobilních pracovních strojů a pojížděného podloží." Doctoral thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2010. http://www.nusl.cz/ntk/nusl-233912.

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This dissertation thesis is concerning with an interaction between mobile working machines and rolled surfaces. Machines and their constructions parts behavior were observed. There are some machines that can change state of surface. And due to these change of surface the machine is in different conditions for drive and also for works. The interaction of working machines and rolled surfaces was categorized in this work and for each category here is a methodic work flow for solution of various cases. Three examples are described in this work. Some simulating programs were used for all cases and therefore there is a methodic work flow for creating and simulating of models. Three described examples include a complex solution of hydraulic drive for vibration exciter of vibration roller, small cleaner of canalizations with aim on load case to frame of this cart. The third example describes solution of undercarriage frames of agricultural semi-trailers. This example is the most extensive chapter from this work due to including of marketing research at the beginning of development and also verification of simulated results with results from real prototype tests at the end of development of these undercarriage frames.
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9

Gerec, Matúš. "Pohonný a brzdový systém motorového vozu železnice pro muzeum průmyslových železnic." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2017. http://www.nusl.cz/ntk/nusl-318852.

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This thesis deals with the design of the propulsion and braking system for narrow gauge railcar. It contains the design of hydrostatic drive system with closed-loop hydraulic circuit. Then thesis describes the concept of propulsion system placement in the frame of the railcar and design of the braking system.
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10

Онуцький, Віталій Григорович, Віталій Олегович Колодій, Vitaly Onutsky та Vitaly Kolodiy. "Розроблення автоматизованого стенду для дослідження вібростійкості електрообладнання". Master's thesis, Тернопільський національний технічний університет ім. І. Пулюя, Факультет прикладних інформаційних технологій та електроінженерії, Кафедра автоматизації технологічних процесів і виробництв, 2021. http://elartu.tntu.edu.ua/handle/lib/36718.

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Робота виконана на кафедрі автоматизації технологічних процесів і виробництв факультету прикладних інформаційних технологій та електроінженерії Тернопільського національного технічного університету імені Івана Пулюя Міністерства освіти і науки України. Захист відбудеться «23» грудня 2021р. о 9.00год. на засіданні екзаменаційної комісії №22 у Тернопільському національному технічному університеті імені Івана Пулюя.
В кваліфікаційній роботі подано результати аналізу та синтезу системи автоматизованого керування стендом для вібраційних досліджень електротехнічних установок та агрегатів. Дослідження проводились з використанням методів імітаційного моделювання та статистичного аналізу. У результаті проведеного дослідження виконано умови щодо стійкості та якості роботи розробленої системи. Розроблено математичні моделі автоматизованої системи управління та доведено її достовірність.
The qualification work presents the results of analysis and synthesis of automated stand control system for vibration studies of electrical installations and units. The research was conducted using simulation methods and statistical analysis. As a result of the study, the conditions for the stability and quality of the developed system were met. Mathematical models of the automated control system are developed and its reliability is proved.
Анотація 4 Перелік основних позначень та скорочень 7 Вступ 8 1 Аналітична частина 10 1.1 Відпрацювання міцності електронної техніки методом дослідження вібростійкості 10 1.2 Системи для дослідження вібростійкості промислової продукції фірми Bruel & Kjaer 11 1.3 Системи дослідження вібростійкості компанії LDS 16 1.4 Принцип дії і характеристики сучасних вібродатчиків 17 2 Технологічна частина 30 2.1 Статистичний аналіз систем автоматичного управління 30 2.2 Детермінована та статистична ідентифікація САУ 40 2.3 Вибір і обгрунтування аналогів розроблюваної автоматизованої системи 49 3 Конструкторська частина 53 3.1 Особливості та область призначення установок для дослідження вібростійкості 53 3.2 Аналітичне дослідження системи і створення її математичної моделі 59 3.3 Розроблення засобів безпечної експлуатації віброустановки 65 4 Науково-дослідна частина 71 4.1 Статистична лінеаризація при дослідженні експлуатаційних режимів роботи слідкуючого вібраційного стенду 71 4.2 Результати моделювання та дослідження створених моделей у середовищі MathLab 80 4.3 Перевірка достовірності моделі системи згідно еталонного управляючого сигналу 84 5 Спеціальна частина 90 5.1 Розробка креслень в системі AutoCAD 90 5.2 Використання пакету прикладних програм MathLab для проведення дослідження 93 6 Охорона праці та безпека в надзвичайних ситуаціях 95 6.1 Заходи з охорони праці 95 6.2 Заходи з безпеки в надзвичайних ситуаціях 103 Висновки 109 Перелік посилань 110
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Книги з теми "Hydraulic drive system"

1

Mikkola, Aki. Studies on fatigue damage in a hydraulically driven boom system using virtual prototype simulations. Lappeenranta: Lappeenranta University of Technology, 1997.

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2

Vol'vak, Sergey. Hydraulics. Workshop. ru: INFRA-M Academic Publishing LLC., 2020. http://dx.doi.org/10.12737/1045068.

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Study guide corresponds to the program discipline "Hydraulics". Consists of two parts and is for carrying out practical and laboratory works. The first part provides material on the basics of the calculation of hydraulic machines, hydraulic drives of agricultural machinery, systems of land reclamation and hydraulic transport for development of skills of application of theoretical information to solve specific technical problems and development practices of hydraulic calculations. The second part contains material for the study of the methods and instruments for measuring pressure, the study of the equation of Bernoulli, determination of hydraulic resistance, the study of the structure and principles of operation of positive displacement pumps and dynamic-type, cylinders, volumetric hydraulic drive and hydrodynamic transmission elements and schemes of irrigation systems and agricultural water supply. To conduct practical and laboratory classes for students of all forms of training in the direction of training 35.03.06 "Agroengineering", as well as for graduate students, teachers and technical workers of agriculture.
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3

Mahaffy, Philip Robert. Replacement of the existing combined hydraulic and electro-mechanical controls on the Autoleveller system fitted to the Lummus Mackie Mark 3 Speedmack textile machine, with the latest in AC Servo drive technology, an industrial microprocessor and electronic hardware. [S.l: The Author], 1992.

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4

Beater, Peter. Pneumatic Drives: System Design, Modelling and Control. Springer, 2010.

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5

Beater, Peter. Pneumatic Drives: System Design, Modelling and Control. Springer, 2007.

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6

Technisches Englisch-Deutsch Wörterbuch Automobiltechnik Kraftfahrzeugtechnik Luftfahrt kfz-Mechatronik: Technische Fachbegriffe werden mit einer autocomplete-suche / auto-vervollständige suche gefunden. 63500 Seligenstadt, Germany: Verlag Lehrmittel Wagner, 2010.

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Частини книг з теми "Hydraulic drive system"

1

Demircioğlu, Pınar, İsmail Böğrekçi, and Mehmet Temel. "Development of Hydraulic Drive Railway Bearings Installation System." In Lecture Notes in Mechanical Engineering, 866–75. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-62784-3_72.

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2

Woś, Piotr, and Ryszard Dindorf. "Modeling and Analysis of the Hydraulic Servo Drive System." In Advances in Intelligent Systems and Computing, 253–62. Cham: Springer International Publishing, 2015. http://dx.doi.org/10.1007/978-3-319-26886-6_16.

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3

Fomenko, N. A., S. V. Aleksikov, and S. G. Artemova. "Actuation Control System of a Hydraulic Machine Drive Locking Device." In Lecture Notes in Mechanical Engineering, 1191–97. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-54817-9_138.

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4

Możaryn, Jakub, Arkadiusz Winnicki, and Damian Suski. "Modeling of Electro-Hydraulic Servo-Drive for Advanced Control System Design." In Springer Proceedings in Mathematics & Statistics, 183–91. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-77306-9_16.

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5

Knap, Lech, Wiesław Grzesikiewicz, and Michał Makowski. "A New Approach to Design of a Cyberphysical System Exemplified by Its Use in the Electro-Hydraulic Hybrid Drive." In Advances in Intelligent Systems and Computing, 22–31. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-97490-3_3.

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Mizukami, Hideki, Takuya Otani, Juri Shimizu, Kenji Hashimoto, Masanori Sakaguchi, Yasuo Kawakami, Hun-ok Lim, and Atsuo Takanishi. "Investigation of Parallel Connection Circuit by Hydraulic Direct-Drive System for Biped Humanoid Robot Focusing on Human Running Motion." In ROMANSY 23 - Robot Design, Dynamics and Control, 34–42. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-58380-4_5.

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Heinen, Frank, and Peter Eberspächer. "Hydraulic modulator." In Brakes, Brake Control and Driver Assistance Systems, 134–41. Wiesbaden: Springer Fachmedien Wiesbaden, 2014. http://dx.doi.org/10.1007/978-3-658-03978-3_10.

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Remfrey, James, Steffen Gruber, and Norbert Ocvirk. "Hydraulic Brake Systems for Passenger Vehicles." In Handbook of Driver Assistance Systems, 703–30. Cham: Springer International Publishing, 2015. http://dx.doi.org/10.1007/978-3-319-12352-3_30.

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Remfrey, James, Steffen Gruber, and Norbert Ocvirk. "Hydraulic Brake Systems for Passenger Vehicles." In Handbook of Driver Assistance Systems, 1–23. Cham: Springer International Publishing, 2015. http://dx.doi.org/10.1007/978-3-319-09840-1_30-1.

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10

Bitó, János F., József K. Tar, and Imre J. Rudas. "Novel Adaptive Control of Mechanical Systems Driven by Electromechanical Hydraulic Drives." In Knowledge and Technology Integration in Production and Services, 517–24. Boston, MA: Springer US, 2002. http://dx.doi.org/10.1007/978-0-387-35613-6_59.

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Тези доповідей конференцій з теми "Hydraulic drive system"

1

Minav, Tatiana A., Panu Sainio, and Matti Pietola. "Direct-Driven Hydraulic Drive Without Conventional Oil Tank." In ASME/BATH 2014 Symposium on Fluid Power and Motion Control. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/fpmc2014-7834.

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In the past few years, direct-driven hydraulic drive (DDH) has synthesized the advantages of compact high power of the hydraulic system and flexible control of the electric motor. This paper investigates the direct-driven hydraulic setup for the non-road mobile machinery (NRMM) application. In the proposed setup, the speed and position control of a double-acting cylinder is implemented directly with a Synchronous Torque Motor drive in a close-loop system without conventional control valves and oil tank. In relation to this, hydraulic accumulator is employed as a replacement of the conventional oil tank. For position and speed control of this closed-loop system, only single feedback is applied from motor’s rotor encoder. As a result, excellent control capabilities of a modern electric drive brings along safety functions and monitoring capabilities of the motor and controller to benefit the hydraulic system. Functionalities of motor controllers offer opportunities to duplicate conventional sensors based on either safety or reliability demands. The system is investigated by means of measurements and also simulation models.
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Štefane, Matevž, and Darko Lovrec. "Modern control system for servo hydraulic linear drive." In International conference Fluid Power 2017. University of Maribor Press, 2017. http://dx.doi.org/10.18690/978-961-286-086-8.8.

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3

Ruan, Xiao, Weiguo Zhu, and Chi Zhang. "Design and Calculation of Hydraulic System for Full Hydraulic Drive Paddy Field Transplanter." In 2nd International Conference on Computer Engineering, Information Science & Application Technology (ICCIA 2017). Paris, France: Atlantis Press, 2017. http://dx.doi.org/10.2991/iccia-17.2017.166.

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Gradl, Christoph, Ivo Kovacic, and Rudolf Scheidl. "Development of an Energy Saving Hydraulic Stepper Drive." In 8th FPNI Ph.D Symposium on Fluid Power. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/fpni2014-7809.

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Stepper drives can realize quite precise, incremental motions without position sensors. Sensorless hydraulic motion control is strongly demanded by industry and, therefore, is an established idea in hydraulics for a while. Some concepts have been proposed in the past and a few of them have also been realized and applied in specific cases. But it is expected that digital hydraulics — due to its intrinsic discrete nature — can create new, more advantageous hydraulic versions of stepper drives. In this paper, a new stepper drive is presented and investigated. It creates the steps by fixed fluid quanta generated by a so called digital flow unit. That unit is realized by a hydraulic cylinder-piston unit which displaces a defined fluid quantum by each limited forward stroke of that piston. The unit is controlled by a fast switching valve which connects the piston areas alternately with the pressure-, tank- and output-line. The return motion is generated by a return spring. Energy saving is accomplished by storing the supply pressure surplus intermediately in the kinetic energy of the piston and converting that energy to displace part of the quantum to the consumer line without hydraulic energy from the supply line. Different detail concepts of this stepper drive are theoretically assessed. The transient behavior, the performance characteristics and the energy efficiency of a preferred concept are investigated by mathematical modeling and simulation. Furthermore, the main system parameters are identified and corresponding basic dimensioning rules are presented. In a second step, the influence of finite switching times of the valves, the hydraulic impedances of the various flow channels and of the dead volumes and the dynamical properties of the hydraulic cylinder attached to the device, are discussed.
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Noskievic, Petr. "Control of the hydraulic drive using embedded control system." In 2013 14th International Carpathian Control Conference (ICCC). IEEE, 2013. http://dx.doi.org/10.1109/carpathiancc.2013.6560549.

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YANG, Jianxi, Liying WANG, and Jian HUANG. "Analysis of Dynamic Performances for Servo Drive Hydraulic System." In The 2015 International Conference on Mechanical Engineering and Control Systems (MECS2015). WORLD SCIENTIFIC, 2016. http://dx.doi.org/10.1142/9789814740616_0041.

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7

Daley, S. "Intelligent control of an electro-hydraulic rotary drive system." In International Conference on Control '94. IEE, 1994. http://dx.doi.org/10.1049/cp:19940217.

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8

Jianing Liang, Jin-Woo Ahn, and Dong-Hee Lee. "High performance hydraulic pump system using switched reluctance drive." In 2007 International Conference on Electrical Machines and Systems. IEEE, 2007. http://dx.doi.org/10.1109/icems12746.2007.4412272.

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9

Schmidt, Lasse, Henrik C. Pedersen, Viktor H. Donkov, and Torben O. Andersen. "Analysis and Control of a Self-Contained Hydraulic Winch Drive." In BATH/ASME 2018 Symposium on Fluid Power and Motion Control. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/fpmc2018-8889.

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This paper is considering the analysis and control of a self-contained hydraulic winch drive. Winch drives are used in various industries, and especially in offshore and marine applications such as fishing vessels, active heave compensation applications, cranes, oil- and gas drilling rigs, vessels for wind turbine installation and so forth. When high loads are present, such winches are typically actuated by use of hydraulics, and a main disadvantage of hydraulic actuation compared to electrical actuation is the potentially large installation space required due to the hydraulic power unit. In this paper the analysis of- and control design for a self-contained hydraulic winch drive are considered. The drive includes a single supply pump, fixed displacement motor, flow control valve, a boot-strap reservoir and integrated boost-flow functionality. Emphasis is placed on the analysis of the highly coupled dynamics, an approach to decouple the dynamics and a robust control structure able to handle various types of loads aided by model reference generation. The motion performance and robustness properties are demonstrated through simulation results, when the system is subjected to a strongly varying external load and motion reference from an offshore wind turbine blade installation system.
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Zhong Liu, Zhong, Zhanwei Zhanwei Gao, Neng Neng Yang, Yuanming Yuanming Huo, and Junjun Junjun Liu. "Research of Hydraulic Drive Control System in Hydraulic Elevator Based on P-Q Valve." In 2015 International Conference on Mechanical Science and Engineering. Paris, France: Atlantis Press, 2016. http://dx.doi.org/10.2991/mse-15.2016.5.

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Звіти організацій з теми "Hydraulic drive system"

1

Snyder, Victor A., Dani Or, Amos Hadas, and S. Assouline. Characterization of Post-Tillage Soil Fragmentation and Rejoining Affecting Soil Pore Space Evolution and Transport Properties. United States Department of Agriculture, April 2002. http://dx.doi.org/10.32747/2002.7580670.bard.

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Tillage modifies soil structure, altering conditions for plant growth and transport processes through the soil. However, the resulting loose structure is unstable and susceptible to collapse due to aggregate fragmentation during wetting and drying cycles, and coalescense of moist aggregates by internal capillary forces and external compactive stresses. Presently, limited understanding of these complex processes often leads to consideration of the soil plow layer as a static porous medium. With the purpose of filling some of this knowledge gap, the objectives of this Project were to: 1) Identify and quantify the major factors causing breakdown of primary soil fragments produced by tillage into smaller secondary fragments; 2) Identify and quantify the. physical processes involved in the coalescence of primary and secondary fragments and surfaces of weakness; 3) Measure temporal changes in pore-size distributions and hydraulic properties of reconstructed aggregate beds as a function of specified initial conditions and wetting/drying events; and 4) Construct a process-based model of post-tillage changes in soil structural and hydraulic properties of the plow layer and validate it against field experiments. A dynamic theory of capillary-driven plastic deformation of adjoining aggregates was developed, where instantaneous rate of change in geometry of aggregates and inter-aggregate pores was related to current geometry of the solid-gas-liquid system and measured soil rheological functions. The theory and supporting data showed that consolidation of aggregate beds is largely an event-driven process, restricted to a fairly narrow range of soil water contents where capillary suction is great enough to generate coalescence but where soil mechanical strength is still low enough to allow plastic deforn1ation of aggregates. The theory was also used to explain effects of transient external loading on compaction of aggregate beds. A stochastic forInalism was developed for modeling soil pore space evolution, based on the Fokker Planck equation (FPE). Analytical solutions for the FPE were developed, with parameters which can be measured empirically or related to the mechanistic aggregate deformation model. Pre-existing results from field experiments were used to illustrate how the FPE formalism can be applied to field data. Fragmentation of soil clods after tillage was observed to be an event-driven (as opposed to continuous) process that occurred only during wetting, and only as clods approached the saturation point. The major mechanism of fragmentation of large aggregates seemed to be differential soil swelling behind the wetting front. Aggregate "explosion" due to air entrapment seemed limited to small aggregates wetted simultaneously over their entire surface. Breakdown of large aggregates from 11 clay soils during successive wetting and drying cycles produced fragment size distributions which differed primarily by a scale factor l (essentially equivalent to the Van Bavel mean weight diameter), so that evolution of fragment size distributions could be modeled in terms of changes in l. For a given number of wetting and drying cycles, l decreased systematically with increasing plasticity index. When air-dry soil clods were slightly weakened by a single wetting event, and then allowed to "age" for six weeks at constant high water content, drop-shatter resistance in aged relative to non-aged clods was found to increase in proportion to plasticity index. This seemed consistent with the rheological model, which predicts faster plastic coalescence around small voids and sharp cracks (with resulting soil strengthening) in soils with low resistance to plastic yield and flow. A new theory of crack growth in "idealized" elastoplastic materials was formulated, with potential application to soil fracture phenomena. The theory was preliminarily (and successfully) tested using carbon steel, a ductile material which closely approximates ideal elastoplastic behavior, and for which the necessary fracture data existed in the literature.
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