Dissertations / Theses: 'Hydraulic servo system'

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Kennedy, Joseph L. Fales Roger. "Force control of a hydraulic servo system." Diss., Columbia, Mo. : University of Missouri--Columbia, 2009. http://hdl.handle.net/10355/6582.

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The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Title from PDF of title page (University of Missouri--Columbia, viewed on November 18, 2009). Thesis advisor: Dr. Roger Fales. Includes bibliographical references.

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Jackson, Philip Richard. "Optically-powered normally-closed fail-safe hydraulic valves." Thesis, Brunel University, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.288768.

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KOWTA, SRINIVAS. "ROBUST STABILITY ANALYSIS OF SERVO-HYDRAULIC SYSTEM IN PARAMETER SPACE." University of Cincinnati / OhioLINK, 2003. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1060970575.

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Lu, C. "On-line self-optimisation of an electro-hydraulic servo control system." Thesis, University of Salford, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.381828.

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Efe, Yalcin. "Dynamic Model of a Hydraulic Servo System for a Manipulator Robot." Thesis, KTH, Elektrisk energiomvandling, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-152800.

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In this master thesis, a mathematical model of a hydraulic servo system for a manipulator robot is completed by using several different methodologies. The models proposed are particularly tuned for the DeLaval VMS robotic arm. The parameter identification of the robotic arm is accomplished by dividing the model into several subsystems and investigating each system separately by using catalogue data, experimental data and construction drawings. Furthermore, the assumptions are proposed based on the literature review and the expertise of in-house engineers. After completion of parameter identification several different mathematical models including linear and nonlinear methodologies are introduced. It is demonstrated that the improvednonlinear model can successfully mimic the movement of the robotic arm with relatively small errors and it is found to be fairly reliable. Moreover, the errors incurred when chamber pressures are compared with experimental data are found to be relatively small. Furthermore, the improved linear model have successfully delivered an accurate position estimation especially for the medium valve opening, while the chamber pressures are relatively less accurately predicted. The study further carries out sensitivity (uncertainty) analyses to investigate the crucial parameters of the model since it is sometimes very problematic to precisely estimate these parameters. It is found out that the flow coefficient and supply pressures have remarkable impact on the results of the simulations. Therefore, it is strongly advised that these parameters should be very carefully evaluated during the modeling process. Finally the bulk modulus models are compared and the influence of the bulk modulus is revealed.

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Valilou, Shirin. "Nonlinear Model and Control of Electro Hydraulic Servo-Systems." Doctoral thesis, Università degli studi di Bergamo, 2018. http://hdl.handle.net/10446/104971.

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In many applications, the use of hydraulic drives is still preferable to other driving powers. For instance, in shaking table systems for simulating earthquake signal, hydraulic actuators are still widely applied, because the technology of electrical actuators does not(yet) provide the superior performance of hydraulic actuators in generating high power to weight ratio. However, with increasing demands on the performance of complex motion systems, the limits of performance of hydraulic servo-systems, due to the nonlinear and dynamic characteristics of these systems, come into the picture. Most nonlinearities of these systems arise from compressibility of the hydraulic fluid, the complex flow properties of the servo-valve, valve overlap and friction in the hydraulic cylinder. Aside from the nonlinear nature of the hydraulic dynamics, there are many considerable model uncertainties, such as internal and external leakages and external disturbances which cannot be modeled exactly. Therefore, in order to design a high performance controller for simulating the earthquake signal which is the goal of a servo-hydraulic shaking table, a suitable dynamical model of the system needs to be formulated. In this thesis beside a specific application of hydraulic actuator, a shaking table servo system, an integrated approach to the modeling and control of a hydraulic servo system is presented. The application of servo-hydraulic shaking table shows that the dynamics and nonlinearities of the servo-valve and the compressibility of hydraulic oil which basically constitute the limits of the performance of the controlled servo-system. Especially, in case of acceleration model and control of a hydraulic servo-system. In the shaking table application, for modeling and identification of the system, in contrary of the previous works which in them position and pressure sensors are used, only the position and acceleration sensor are available. In order to obtain structural insight in the way that the performance is limited by the properties of (the subsystems of) the hydraulic servo-system, the modeling of this system has been treated thoroughly in this thesis. At the one hand, this has opened the way to model-based control design, so that unavoidable limits of performance can be narrowly approached. At the other hand, the obtained insight appears to be useful in the system design stage, such that potential control problems may be avoided by proper system design. Because of the twofold purpose of the modeling, with control design requiring quantitatively accurate models and simulating the behavior of the system precisely which requiring qualitative insight in the system behavior, the so-called grey-box modeling approach has been applied. This approach comprises physical modeling including model analysis by means of simulation, and subsequent identification and validation of the obtained physical models, using experimental data. In the physical modeling stage, a consistent integration of the nonlinear dynamic modeling of the different subsystems of the hydraulic servo-system, namely servo-valve and actuator are presented. In this model, the most nonlinearities of the system which arise from compressibility of the hydraulic fluid, the complex flow properties of the servo-valve, valve overlap and friction in the hydraulic cylinder are simulated. Four different kinds of friction model are considered and the accuracy of these models for simulating the behavior of the system are compared experimentally. However, due to the limitation of these models in high velocity and bandwidth, it has been shown that for simulating the behavior of the system, nonlinear modeling of the friction is not enough. Then, by gathering some position and acceleration information of the real system, the sensitivity of the model to different nonlinearity of the system are investigated. This led to the insight, that only some of the modeled nonlinear effects are really relevant, such as the nonlinear flow characteristic of the servo-valve spool due to non-ideal port geometries and the compressibility of hydraulic oil, and the position dependence of the actuator dynamics. Based on the experimental results, two new nonlinear dynamic models for simulating the behavior of the servo-hydraulic shaking table are proposed. First, with defining 6 main parameters of the model and identifying them for different sinusoidal inputs, a neural network model is proposed. Second, a new empirical nonlinear model for effective bulk modulus of hydraulic oil is proposed which increase the accuracy of the model to predict the behavior of the position and acceleration output of the system. In this approach, the link between the physical and the system theoretic interpretation of the properties of the hydraulic servo system are strongly emphasized. This makes, that the presented models are not only useful for shaking table design, but also for the design of the hydraulic servo-system. Based on the task specification of the shaking table which is tracking the position and velocity reference signals with considering uncertain load conditions, different kinds of robust controller design are presented. For control designing purpose, the full order dynamic model of the system is simplified in a new approach and then due to the availability of only the position sensor on the experimental setup, a robust sliding mode observer is designed which can estimate the velocity and acceleration states of the system from the position sensor. Finally, experiments with a hydraulic actuator in a single degree-of-freedom setup have shown the validity of the approach for control design. The experimental results of the closed loop system controlling by three different controllers (feed forward PI controller, sliding mode and super twisting controller) with considering different load condition and reference signals are presented. An analysis of different control strategies for this setup led to the conclusion, that super twisting sliding mode controller shows a smaller error and smother response for position and velocity trajectory tracking with respect to sliding mode and feedforward PI controller.

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Viennet, Emmanuel, and Loïc Bouchardy. "Preliminary design and testing of a servo-hydraulic actuation system for an autonomous ankle exoskeleton." Technische Universität Dresden, 2020. https://tud.qucosa.de/id/qucosa%3A71229.

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The work presented in this paper aims at developing a hydraulic actuation system for an ankle exoskeleton that is able to deliver a peak power of 250 W, with a maximum torque of 90 N.m and maximum speed of 320 deg/s. After justifying the choice of a servo hydraulic actuator (SHA) over an electro hydrostatic actuator (EHA) for the targeted application, some test results of a first functional prototype are presented. The closed-loop unloaded displacement frequency response of the prototype shows a bandwidth ranging from 5 Hz to 8 Hz for displacement amplitudes between +/-5mm and +/- 20mm, thus demonstrating adequate dynamic performance for normal walking speed. Then, a detailed design is proposed as a combination of commercially available components (in particular a miniature servo valve and a membrane accumulator) and a custom aluminium manifold that incorporates the hydraulic cylinder. The actuator design achieves a total weight of 1.0 kg worn at the ankle.

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Wang, Lijian. "Force equalization for active/active redundant actuation system involving servo-hydraulic and electro-mechanical technologies." Thesis, Toulouse, INSA, 2012. http://www.theses.fr/2012ISAT0038/document.

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L'évolution vers les avions plus électriques engendre des efforts importants pour développer des actionneurs à source de puissance électrique pour les commandes de vol. Pour de telles applications critiques, il est peut être intéressant dans le futur d'associer à une même surface de contrôle un actionneur conventionnel à source de puissance hydraulique et un actionneur à source de puissance électrique mais ceci pose un problème important lorsque les deux actionneurs sont actifs simultanément: comme chacun essaye d'imposer sa position à l'autre,les deux actionneurs luttent l'un contre l'autre en développant des efforts néfastes qui ne sont pas utilisés par la charge. L'objet du présent travail est de proposer des stratégies d’égalisation d’effort pour un système d'actionnement impliquant ces deux types d''actionneurs opérant en mode actif-actif. La première étape est de concevoir leur commande en position et de la valider sur banc d'essai. Un banc d'essai virtuel fidèle à la réalité est ensuite réalisé dans l'environnement de simulation AMESim pour pouvoir évaluer facilement les différentes stratégies d'égalisation d'effort entre les deux actionneurs. Ces stratégies sont proposées et évaluées virtuellement en deux étapes, statique puis dynamique. Pour finir, une étude de robustesse est réalisée a posteriori pour évaluer la sensibilité des indicateurs de performance aux incertitudes sur les modèles de simulation et sur les points et les conditions de fonctionnement
On the way to more electric aircraft (MEA), more and more power-by-wire (PBW) actuators are involved in the flight control system. For a hybrid redundant actuation system composed by the conventional hydraulically powered actuators and the PBW actuators, one major issue while they operate on active/active mode is the force fighting between channels. As the grave influence of force fighting on accelerating material fatigue and increasing power consumption,it must be addressed with attention. This thesis was aiming at proposing some effective force equalization control strategies for the hybrid actuation system involving one servo-hydraulic actuator (SHA) and one electro-mechanical actuator (EMA). For this objective, the position controllers for SHA and EMA were designed and validated as a first step. Then, a virtual test bench regarding to the realistic behaviors was built in the AMESim simulation environment to accelerate the controller design and enable the robustness study. Following this, 2 static force equalization control strategies were proposed and experimentally validated. The first strategy hat introduced integral force fighting signal to compensate the actuator position control was proved a good candidate solution. In the next part, 3 dynamic force equalization strategies were proposed and assessed on the virtual test bench. Their performance sensitivities to the parameter uncertainties were studied through Monte-Carlo method. The first strategy that introduced velocity and acceleration feed-forwards to force the SHA and EMA having similar pursuit dynamics showed a good force equalization performance as well as good segregation and good robustness. In the end, the work presented in thesis was concluded and perspective was given to the ongoing work

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Hochwallner, Martin. "On Motion Control of Linear Incremental Hydraulic Actuators." Doctoral thesis, Linköpings universitet, Industriell Produktion, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-142264.

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Linear Incremental Hydraulic Actuators combine one or more short-stroke cylinders, and two or more engaging/disengaging mechanisms into one actuator with long, medium, or even unlimited stroke length. The motion of each single short-stroke actuator concatenated by the engaging/disengaging mechanisms forms the motion of the linear incremental hydraulic actuator. The patterns of how these motions are concatenated form the gaits of a specific linear incremental hydraulic actuator. Linear incremental hydraulic actuators may have more than one gait. In an application, the gaits may be combined to achieve optimal performance at various operating points. The distinguishing characteristic of linear incremental hydraulic actuators is the incremental motion. The term incremental actuator is seen as analogous to the incremental versus absolute position sensor. Incremental actuators realize naturally relative positioning. Incremental motion means also that the behavior does not depend on an absolute position but only on the relative position within a cycle or step. Incremental actuators may realize discrete incremental or continuous incremental motion. Discrete incremental actuators can only approach discrete positions, whereby stepper drives are one prominent example. In contrast, continuous incremental actuators may approach any position. Linear electric motors are one example of continuous incremental actuators. The actuator has no inherent limitation in stroke length, as every step or cycle adds only to the state at the beginning of the step or cycle and does not depend on the absolute position. This led to the alternative working title Hydraulic Infinite Linear Actuator. Linear incremental hydraulic actuator provides long stroke, high force, and linear motion and has the potential to decrease the necessary resource usage, minimize environmental impact, e.g. from potential oil spillage, extend the range of feasible products: longer, stiffer, better, etc. This thesis presents an analysis of the characteristics and properties of linear incremental hydraulic actuators as well as the gaits and possible realizations of some gaits. The gait for continuous, smooth motion with two cylinders is comprehensively studied and a control concept for the tracking problem is proposed. The control concept encapsulates the complexity of the linear incremental hydraulic actuator so that an application does not have to deal with it. One other gait, the ballistic gait, which realizes fast, energy-efficient motion, enabling energy recuperation is studied.

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Ho, Hon Ping. "The Influence of Braking System Component Design Parameters on Pedal Force and Displacement Characteristics. Simulation of a passenger car brake system, focusing on the prediction of brake pedal force and displacement based on the system components and their design characteristics." Thesis, University of Bradford, 2009. http://hdl.handle.net/10454/7447.

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This thesis presents an investigation of braking system characteristics, brake system performance and brake system component design parameters that influence brake pedal force / displacement characteristics as ‘felt’ by the driver in a passenger car. It includes detailed studies of individual brake system component design parameters, operation, and the linear and nonlinear characteristics of internal components through experimental study and simulation modelling. The prediction of brake pedal ‘feel’ in brake system simulation has been achieved using the simulation modelling package AMESim. Each individual brake system component was modelled individually before combining them into the whole brake system in order to identify the parameters and the internal components characteristics that influence the brake pedal ‘feel’. The simulation predictions were validated by experimentally measured data and demonstrated the accuracy of simulation modelling. Axisymmetric Finite Element Analysis (using the ABAQUS software) was used to predict the behaviour of nonlinear elastomeric internal components such as the piston seal and the booster reaction disc which was then included in the AMESim simulation model. The seal model FEA highlighted the effects of master cylinder and caliper seal deformation on the brake pedal ‘feel’. The characteristics of the brake booster reaction disc were predicted by the FEA and AMESim simulation modelling and these results highlighted the importance of the nonlinear material characteristics, and their potential contribution to brake pedal ‘feel’ improvement. A full brake system simulation model was designed, prepared, and used to predict brake system performance and to design a system with better brake pedal ‘feel’. Each of the brake system component design parameters was validated to ensure that the braking system performance was accurately predicted. The critical parameter of brake booster air valve spring stiffness was identified to improve the brake ‘pedal ‘feel’. This research has contributed to the advancement of automotive engineering by providing a method for brake system engineers to design a braking system with improved pedal ‘feel’. The simulation model can be used in the future to provide an accurate prediction of brake system performance at the design stage thereby saving time and cost.

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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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Oliver, Danielle Simonette. "Power Requirements of Control Surface Actuators Towards Active Aeroelastic Control Using the Method of Receptances." Miami University / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=miami159601703575348.

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ALVA, JUAN GERARDO CASTILLO. "LEARNING CONTROL OF HIGH FREQUENCY SERVO: HYDRAULIC SYSTEMS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2008. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=12419@1.

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COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
Sistemas hidráulicos são usados onde se requerem forças e torques relativamente altos, alta velocidade de resposta para o início, parada e reversão da velocidade. Eles são usados em sistemas industriais, em robótica, simuladores de movimento, plantas automatizadas, exploração de minérios, prensas, e especialmente em sistemas de testes de fadiga de materiais. As máquinas de testes de fadiga baseadas em sistemas servo-hidráulicos têm como propósito fazer ensaios nos materiais para prever a vida útil em serviço. Os ensaios de fadiga são quase sempre independentes da freqüência de trabalho. Para uma dada resistência do material e magnitudes das tensões alternadas e médias aplicadas, a vida à fadiga depende essencialmente do número de ciclos de carga aplicados ao material testado. Por esse motivo, trabalhar com a máquina de ensaios de materiais a uma freqüência elevada traz vantagens de redução de tempo e custo dos ensaios, sem interferir nos resultados. A aplicação da carga pode ser repetida milhões de vezes, em freqüências típicas de até cem vezes por segundo para metais. Para se atingirem estas freqüências, relativamente altas para um teste de fadiga, é necessário um sistema de controle eficiente. Nesta dissertação, técnicas de controle por aprendizado são desenvolvidas e aplicadas a uma máquina de ensaios de materiais, permitindo a aplicação de carregamentos de amplitude variável em alta freqüência. A metodologia proposta consiste em fazer um controle do tipo bang-bang, restringindo à servo-válvula do sistema a trabalhar sempre nos seus limites extremos de operação, i.e., procurando mantê-la sempre completamente aberta em uma ou outra direção. Devido à dinâmica do sistema, os pontos de reversão devem ficar antes dos picos e vales de força ou tensão desejada. O instante de reversão é um parâmetro que depende de diversos fatores, como a amplitude e carga média da solicitação, e também é influenciado por zonas mortas causadas, e.g., por folgas na fixação dos corpos de prova. Para que a servo-válvula trabalhe no limite de seu funcionamento, o algoritmo de aprendizado obtém os instantes ótimos para as reversões, associados a variáveis adimensionais com valores entre 0 e 1, armazenados em tabelas específicas para cada tipo de carregamento. A lei de aprendizado preenche e atualiza constantemente os valores das tabelas durante a execução dos testes, melhorando a resposta do sistema a cada evento. Apresentam-se a modelagem dinâmica de uma máquina servohidráulica e de sua malha de controle, e simulações comparando o controle PID com o controle por aprendizado proposto. A validação experimental é feita em uma máquina servo-hidráulica de ensaios de fadiga. Para este fim, um software de controle em tempo real foi especialmente desenvolvido e implementado em um sistema computacional CompactRIO. Os resultados demonstram a eficiência da metodologia proposta.
Hydraulic systems are used where relatively high forces and torques are required, or when high response speeds are necessary. They are used in industrial systems, robotics, movement simulators, automated plants, ore exploration, presses, and especially in fatigue testing systems. Fatigue tests are usually performed on servo-hydraulic systems, in order to predict the behavior of materials and their life in service. Fatigue tests are almost always independent of the loading frequency. For a given material and magnitudes of alternate and mean stresses, the fatigue life depends essentially on the number of applied load cycles on the tested material. For this reason, working with the material testing machine at high frequencies brings the advantages of reduction in time and cost, without altering the results. The application of the load can be repeated millions of times, in frequencies of up to one hundred times per second for metals, or even more. To achieve such frequencies, relatively high for a fatigue test, it is necessary to use an efficient control system. In this thesis, learning control techniques are developed and applied to a materials testing machine, allowing the application of constant or variable amplitude loads in high frequency. The proposed methodology consists of implementing a bang-bang type control, restricting the system servo-valve to always work at its extreme limits of operation, i.e., always keeping it completely open in one or the other direction. Due to the system dynamics, the reversion instant must happen before achieving the peaks and valleys of desired force (or stress, strain, etc.). The reversion instant is a parameter that depends on several factors, such as the alternate and mean loading components. It is also influenced by dead zones caused, e.g., by the slack in the mounting between a CTS specimen and the machine pins. As the servo-valve works in its limits of operation, the learning algorithm tries to obtain the optimal instants for the reversions, associating them to a non dimensional variable with values between 0 and 1, stored in specific tables. The learning law constantly updates the values of the table during the execution of the tests, improving the system response. In this work, the dynamic modeling of a servo-hydraulic machine is presented, together with its control scheme. Simulations are performed to compare results from PID and learning controls. The experimental validation is made using a servohydraulic testing machine. For this purpose, real time control software is developed and implemented in a CompactRIO computational system. The results demonstrate the efficiency of the proposed methodology.

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Shukla, Amit. "Stability Analysis and Design of Servo-Hydraulic Systems." University of Cincinnati / OhioLINK, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1030385056.

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Corteline, Carlos Henrique. "On the air in servo valve hydraulic control systems." Instituto Tecnológico de Aeronáutica, 2009. http://www.bd.bibl.ita.br/tde_busca/arquivo.php?codArquivo=1256.

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The present work is a study of the effects of air in hydraulic control system. The study is based on models of: the mixture of air with hydraulic fluid, the servo hydraulic control system and experimental identification. The air mixture model is to evaluate the impact on the fluid properties, the hydraulic system';s one is to assess the impact of changes in the fluid properties in the system performance and identification to estimate the amount of air in the system.

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Jindra, Pavel. "Řízení polohového servomechanismu s nespojitou přestavnou rychlostí." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2012. http://www.nusl.cz/ntk/nusl-230208.

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Diploma thesis work includes simulation of compensation of control for discrete. The aim of the work is a solution positioning control of servomotor drive piston, which is controlled by pass of the pressure oil with the help of several electromagnetically controlled switchboards with the orifice in the output channels. The verification activities of the regulated system is done using simulation in Matlab/Simulink and Matlab/Simulink, Matlab/Hydrosim. The requirement on the created model is to verify the behavior of the system to be modified to be used for the further development of the issue

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Wang, Xiao. "AN ACTIVE DISTURBANCE REJECTION CONTROL SOLUTION FOR ELECTRO-HYDRAULIC SERVO SYSTEMS." Cleveland State University / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=csu1336680153.

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SANCHEZ, ELEAZAR CRISTIAN MEJIA. "ACCELERATED LEARNING AND NEURO-FUZZY CONTROL OF HIGH FREQUENCY SERVO-HYDRAULIC SYSTEMS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2009. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=32823@1.

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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO
COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO
PROGRAMA DE EXCELENCIA ACADEMICA
Nesta dissertação foram desenvolvidas técnicas de controle por aprendizado acelerado e Neuro-Fuzzy, aplicadas em um sistema servo-hidráulico para ensaio de fadiga. Este sistema tem o propósito de fazer ensaios em materiais para prever a resistência à fadiga dos materiais. O trabalho envolveu quatro etapas principais: levantamento bibliográfico, desenvolvimento de um controle por aprendizado acelerado, desenvolvimento de um controle por aprendizado Neuro-Fuzzy, e implementação experimental dos modelos de controle por aprendizado proposto em uma máquina de ensaios de materiais. A implementação do controle por aprendizado acelerado foi feita a partir do modelo de controle desenvolvido por Alva, com o objetivo de acelerar o processo de aprendizagem. Esta metodologia consiste em fazer um controle do tipo bang-bang, restringindo a servo-válvula a trabalhar sempre em seus limites extremos de operação, i.e., procurando mantê-la sempre completamente aberta em uma ou outra direção. Para manter a servo-válvula trabalhando em seus limites de seu funcionamento, os instantes ótimos para as reversões são obtidos pelo algoritmo de aprendizado, e armazenados em tabelas específicas para cada tipo de carregamento. Estes pontos de reversão dependem de diversos fatores, como a amplitude e carga média da solicitação, e são influenciados pela dinâmica do sistema. Na metodologia proposta, a lei de aprendizado inclui um termo de momentum que permite acelerar a aprendizagem dos valores das tabelas constantemente durante a execução dos testes, melhorando a resposta a cada evento. O desenvolvimento de um controle por aprendizado Neuro-Fuzzy foi motivado pela necessidade de ter um agente com a capacidade de aprendizado e armazenamento dos pontos ótimos de reversão. Este modelo de controle também consiste na implementação de um controle do tipo bang-bang, trabalhando com a servo-válvula sempre nos seus limites extremos de operação. O instante de reversão é determinado pelo sistema Neuro-Fuzzy, o qual tem como entradas a gama (dobro da amplitude) e o valor mínimo do carregamento solicitado. O processo de aprendizado é feito pelas atualizações dos pesos do sistema Neuro-Fuzzy, baseado nos erros obtidos durante a execução dos testes, melhorando a resposta do sistema a cada evento. A validação experimental dos modelos propostos é feita em uma máquina servohidráulica de ensaios de fadiga. Para este fim, o algoritmo de controle proposto foi implementado em tempo real em um módulo de controle CompactRIO da National Instruments. Os testes efetuados demonstraram a eficiência da metodologia proposta.
In this thesis, accelerated learning and Neuro-Fuzzy control techniques were developed and applied to a servo-hydraulic system used in fatigue tests. This work involved four main stages: literature review, development of an accelerated learning control, development of a Neuro-Fuzzy control, and implementation of the learning control models into a fatigue testing machine. The accelerated learning control was implemented based on a learning control developed in previous works, introducing a faster learning law. Both learning control methodologies consist on implementing a bang-bang control, forcing the servovalve to always work in its operational limits. As the servo-valve works in its operational limits, the reversion points to achieve every peak or valley in the desired history are obtained by the learning algorithm, and stored in a specific table for each combination of minimum and mean load. The servo-valve reversion points depend on a few factors, such as alternate and mean loading components, while they are as well influenced by the system dynamics. In the proposed accelerated methodology, the learning law includes one momentum term that allows to speed up the learning process of the table cell values during the execution of the tests. The developed Neuro-Fuzzy control also consists on a bang-bang control, making the servo-valve work in its operational limits. However, here the instant of each reversion is determined by the Neuro-Fuzzy system, which has the load range and minimum load required as inputs. The learning process is made by the update of the Neuro-Fuzzy system weights, based on the errors obtained during the execution of the test.The experimental validation of the proposed models was made using a servo-hydraulic testing machine. The control algorithm was implemented in real time in a C-RIO computational system. The tests demonstrated the efficiency of the proposed methodology.

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Jesus, Sidney Nogueira Pereira de. "Controlador de posição linear hidro-pneumático." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/3/3151/tde-30052008-125213/.

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Nessa pesquisa é apresentada uma inovação tecnológica em aplicações de controle de posição em máquinas e/ou dispositivos: o Controlador de Posição Linear Hidro- Pneumático. Para os casos nos quais têm-se grandes esforços combinados com pequenos deslocamentos, normalmente esse trabalho é feito com o uso de Sistemas Servo-Hidráulcos nos quais, devido às características mencionadas do nicho de mercado visado pela presente proposta, representam um custo elevado quando comparado com a solução Hidro-Pneumática aqui descrita. Salienta-se a simplicidade da infra-estrutura requerida para a instalação dessa alternativa, e também a redução do desperdício energético com relação à tecnologia tradicional com a Servo-Hidráulica. Observou-se nos testes com o protótipo, um excelente desempenho do sistema em termos de rapidez de resposta, como ainda no quesito resolução de posicionamento cujos valores encontrados apresentam-se na casa de 0,05 segundos e 0,01 mm, respectivamente. O pequeno tamanho físico obtido com essa nova tecnologia é outro item relevante, permitindo-se o seu emprego em locais de reduzido espaço disponível. . Resultados de simulações numéricas e de testes experimentais são apresentadas, bem como perspectivas de desenvolvimentos futuros.
This research presents a technological innovation for applications in machine / device position control: the Hydro-Pneumatic Linear Position controller. In cases where great efforts are combined with small dislocations, this task is normally accomplished by means of Servo Hydraulic Systems that, due to particular characteristics of the market envisaged by the present proposition, represent elevated costs, when compared to those of the hydro-pneumatic solution described here. This work presents an analytical numerical model for the devise as well as an experimental prototype. It worth noting the infra-structure simplicity required for this alternative implementation, and also the reduction in energy waste when compared to the traditional servo-hydraulic technology. The prototype experimental tests demonstrated the system excellent behavior in what concerns answer speed and position resolution whose values were respectively in range 0.05 s and 0,01 mm. The small physical size obtained with this technology is another relevant item, which allows the device use in places of reduced available space. Numerical simulation and experimental test results are presented as well as perspectives of future developments

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Wang, Chi-Wei, and 王麒維. "Implementation of Hydraulic Servo Control System." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/33627302981614219015.

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碩士
國立高雄應用科技大學
機械與精密工程研究所
101
In this thesis, to stabilize the liquid pressure-controlled in a water cleaning system, planed and designed of a hydraulic servo control system. The control module is based on the microprocessor and planed PC Based the interface of transmission by RS232 to monitor the pressure value and calculated pressurizing pump differential pressure values and transmit control commands to the microprocessor then drive the servo motor to achieve the stable liquid pressure in a hydraulic servo control system. On the PC side, the design is based on the C# to do compare and correct between the target pressure value and servo motor speeds, while the design of the pressure regulator control method allows hydraulic servo control system can be done effectively stable pressure regulator controls the pressure of the entire system sensing component is the use of pressure transmitters, and pressure value is to capture by A/D card. In the simulation, the motion analyzing of a hydraulic servo control system motion based on PID and Fuzzy controller was done by MATLAB/SIMULINK software. On the experiment, we use C# to create a man-machine interface with the RS232 protocol to send control commands, while using pressure transmitters pass back and forth a hydraulic servo control system pressure values, In the hardware configuration, mainly including a pressurizing pump, serial unit, the power conversion unit, I/O hydraulic pressure sensors(transmitters), the DC motor drive unit(drive and speed control). In this thesis we have built a set of hydraulic servo control system presses by reaching a stability to control of purpose, at the same time letting to add to press system can ensure its clean water effect and stabilize water and add the service life of pressing the system. Rise the function of clean water system further because this system considers to add to press fluctuation and long term that the pressuring pump passes in and out water pressure to supervise and control at the same time, can also consequently reach the pipeline pressure of the hydraulic system variation supervision in addition.

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21

Lai, Chien-Pang, and 賴建邦. "Circuit Realization and Control of Electro-Hydraulic Servo System in Hydraulic Punch." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/rs8dbu.

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碩士
國立勤益科技大學
電機工程系
105
In this paper, the dynamics and control of an electro-hydraulic servo system for a hydraulic press are studied, including modeling, data analysis, optimization of proportional-integral-derivative (PID) control and sliding model control (SMC) and circuit implementation. The electro-hydraulic servo system inside a hydraulic press turns into a nonlinear and unstable system when affected by the nonlinear friction force. In this paper, the system’s motion behaviors are studied through theoretical derivation, modeling and data analysis. Particle swarm optimization (PSO) is also used to determine the optimized PID control parameters that further help control and stabilize the system. Another control method, SMC, is used for comparison. Experimental results indicate that the system can be controlled and its stable periodic motion can be maintained with each of PID and SMC control methods. Finally, the system is implemented with circuit design to verify the feasibility of the experiment, which can be used as reference for future study on an electro-hydraulic servo system for a hydraulic press.

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22

Chen, Chun-Ming, and 陳俊銘. "A PLC-Based Fuzzy PID Controlled Hydraulic Servo System." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/a4xd4g.

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碩士
國立臺北科技大學
自動化科技研究所
93
High nonlinearity and time variation are very common in hydraulic servo systems. The system parameters are varying from time to time and due to different operation conditions. Demands for wide range of operation conditions, such as different positioning range, make a linearization model, linearized around a single operation point, inaccurate to describe the system dynamic behavior. Therefore, a traditional PID controller, which used to work well in a linear system, will not be able to work satisfactorily for the highly nonlinear system with time varying system parameters. In order to counter the problem, we proposed a nonlinear controller of an architecture of fuzzy PID, to dynamically tune the PID gains so that an optimal performance outcome can be obtained. In the past, there are plenty of advanced control strategies have been proposed in literatures to solve the hydraulic servo system, such as fuzzy controller, self-tuning adaptive controller, self-tuning PID controller and robust controller etc. However, most of them were using the PC-based framework. At the time being, PLC is the most popular controller used for manufacturing machines. In this paper, a framework of using PLC as the controller unit, combining the fuzzy PID control strategy, will provide a very high potential solution in practice for the industry of hydraulic servo system applications. This technology will also help domestic companies to build up their own core technology in servo control aspects.

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23

Lo, Wei-Chi, and 羅偉吉. "Application of Adaptive Hybrid Control for Adymmetric Hydraulic Servo System." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/01958157218124065321.

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碩士
龍華科技大學
機械系碩士班
93
Hydraulic devices have been utilized in the industry extensively. It can provide features on production and modernization for the machinery. In general, close loop control within hydraulic servo system, it contains several instabilities such as high-degree, nonlinearity, time-variant and asymmetry; therefore, mathematical model and location control are not easily established by the conventional controller. With consistent developing on adaptive control theories, those instabilities have been resolved gradually from the last decade. Recently, adaptive control is capable of on-line tuning for control parameters in order to achieve performing satisfaction. In this study, adaptive control theorem has been implemented within close loop control for the hydraulic device incorporating with Lyapunov’s stability theorem and Normalized Algorithms into an integrated adjustable type of adaptive switch. With these initiating achievements on the switch, discuss its own advantages and disadvantages then make comparison between Lyapunov’s stability theorem and Normalized Algorithms.

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24

Cheng, Tun-Jen, and 鄭敦仁. "Neural Network Self-Tuning PID Control For Hydraulic Servo System." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/30272423125943887059.

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碩士
東南科技大學
機電整合研究所
99
The high performance electro-hydraulic servo systems (EHSV) need be applied to modern industry. The modern requirements of parameters variations and operation conditions variations become the new challenges for convention PID controls, which have used to be applied to electro-hydraulic servo systems. This paper is concerned with a new architecture of a self-tuning neural-PID control system and its application to control the displacement of an electro hydraulic servo system. This study proposed the three layers back propagation network to auto tuning the parameters of a conventional PID controller. The cylinder displacement of EHSV investigated by simulations, and simulation results reveal the proposed method is available for the EHSV system, and the appropriate PID control parameters can be on-line tuning by the proposed neural networks.

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25

Ye, Kuo Ann, and 葉國安. "Comparison of using proportional and servo valves on position control in a hydraulic servo system." Thesis, 1995. http://ndltd.ncl.edu.tw/handle/82052559507003332329.

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JIANG, JIH-KAI, and 江繼開. "A Study on Hydraulic Servo Position Control System with Hybrid Controller." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/11719570726680477222.

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碩士
逢甲大學
自動控制工程所
92
It is difficult to achieve efficient control time variable and nonlinear hydraulic system with conventional PID controllers. A novel fuzzy PID controller and a fuzzy logic parameter regulator are presented in this paper for design and apply to plant of position control. The emphasis is mainly on the tracking performance. For such a reason, an advanced method to improve the tracking accuracy with low pass filter. In general, the actual electro-hydraulic servomechanism will usually have an unavoidable operating delay time in the solid valve. This may sometimes cause close-loop instability if it was not treated carefully in the control system designs. Therefore, in the proposed control system, an adaptable wavelet network compensator used to compensate for the reduced time delay. In order to realize the proposed design and to evaluate the performance in practical applications, there is construct NI LabVIEW and DAQ card for a high-speed simulation platform with real-time capability. The SIMULINK simulation environment accompanied by LabVIEW Simulation Interface Toolkit（SIT）software package will used as a simulation platform on which a plant under controlled is constructed. Both simulation and experimental results are provided to show the effectiveness of the proposed method. .

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Lin, Chia-ying, and 林佳穎. "Image-Based Servo Control System of 5-DOF Underwater Hydraulic Manipulator." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/64539030614288347733.

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碩士
國立中山大學
海下科技研究所
103
The manipulator control system used in the work-class ROVs (Remotely Operated Vehicles, ROVs) nowadays is the Master-Slave control system. The master side uses a small replica arm to control the underwater manipulator (Slave side). This kind of system is equipped with servo valve or proportional valve pack along with position-feedback provided by rotary encoder. When the operator changes the position of the master controller, it sends the position signal to the slave arm, and the position of the joints would be sensed and fed back to the master controller. The two positions are compared, and the required signal is sended to the valves to activate and adjust the position until the error is reduced to zero. However, the cost of the overall system is high and mass of the hydraulic section is too heavy for observation-class ROVs. The hydraulic manipulators without sensors and valves that can use servo control are lighter, yet, can only be able to move each joint separately through corresponded toggle switches or joysticks. This paper provides an image-based visual servo (IBVS) control system of 5-DOF underwater hydraulic manipulator. By utilizing the visual information we can calculate the actual angle of the joints, and feed back to the controller. On the other hand, introduce the inverse Jacobian matrix to convert the distance between target point and the end-effector of the manipulator into target angles of each joints. Thus, we can compare the two angle signals to adjust each joint of the arm at the same time.

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Tsai, Chung-Pin, and 蔡崇彬. "Servo-hydraulic cylinder position control system using neuro- fuzzy control method." Thesis, 1993. http://ndltd.ncl.edu.tw/handle/57005291642867179035.

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Wang, Yu-Sheng, and 王友聖. "The Investigation of Hydraulic Servo System Design for High-Speed Injection Molding." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/25341812235227930922.

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碩士
中原大學
機械工程研究所
89
3C thin-wall products require to be molded by a high-speed injection molding machines. In this study, we the structure and design of hydraulic proportional-servo valve system in a high-speed injection molding is investigated. The proportional-servo valve was used to build hydraulic platform system. The system can actuate hydraulic forward speed and provide enough flow rate to keep up system stable under the aid of accumulation with and without loading. The human interface was also developed using LabVIEW. HyPneu simulation software used to simulate the system function and compare with experimental data. According to experimental data, we know that the reaction characteristic of proportional-servo valve that used in injection unit will influence the high-speed injection characteristic. Simulation shows well coincidence with measurement.

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30

Chu, Ming-Huei, and 朱明輝. "Direct Neural Controller Applied to DC Motor and Electro-Hydraulic Servo System." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/86772659610172931050.

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博士
中原大學
機械工程學系
90
A direct adaptive neural network controller with specialized learning architecture and its applications are studied in this research. The adaptation law is applied to the direct neural controller for approximating the term of the output layer so that the back propagation iteration can be executed. An arctangent function is applied to be the activation function so that the neural network controller output has negative or positive value. The proposed direct adaptive neural network controllers without reference model are applied to speed and position control of DC motors and position control of Electro-hydraulic servo systems. Simulation shows that a previous training of the neural controller can learn the approximate behavior of the plant and create better initial weights, then followed by on-line trained to fine-tune the network in the operating process. Experiment shows stable and fast responses can be achieved. The same controller with reference model is applied to control the swash plate angle of a variable displacement axial piston pump, which is nonlinear, time variant and with load disturbance. Mathematic simulation and experiment show that the direct adaptive neural network controllers enhance adaptability and robustness of the system and improve the pump performance.

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31

郭天舜. "H∞ Control of an Electrol-hydraulic Acceleration Servo System with a Vertical Load." Thesis, 1997. http://ndltd.ncl.edu.tw/handle/35649811113239402369.

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碩士
國立臺灣大學
造船及海洋工程學研究所
85
Due to the nonlinear and time variant characteristics, the accelerating motion of the electro-hydraulic controlled cylinder system is difficult to control. The purpose of this thesis is to design a mixed sensitivity controller using the H-infmity theorem for the motion control of an electro-hydraulic cylinder system. The design criteria is to achieve good response and robustness for the vertical accelerating motion of the cylinder. The controller is tested by both the numerical simulation and laboratory experiments. The performance of the controller is further compared with experimental results using a controller design by pole-zero cancellation. It is verified that under the temperature, supply pressure and loading variations, the H-infmity controller can overcome system uncertainties and achieve better performance.

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32

SHIH, CHENG-YU, and 施承佑. "Using Taguchi Experimental Method in PID Parameters Adjustment for a Hydraulic Servo System." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/96897332808272733635.

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碩士
臺北城市科技大學
機電整合研究所
104
This thesis deals with a hydraulic servo system by using the tradi-tional PID control technology to investigate the effects of controller parameters with the experimental analysis. In order to achieve the best combination parameters of the controller, the variance analysis is used. During the experiment, a user interface control software is developed by the C++ programming language in Windows system. Once the hydraulic servo system is setting required parameters, such as position, time, error, and controller parameters, the optical device will sample the current position of the hydraulic cylinder and converts this measurement into an electric signal that it passes back to the controller. Then the controller can make necessary adjustments to keep the hydraulic cylinder to meet the setting position. For this goal, Taguchi experimental design is used to find the optimal PID controller parameters, therefore, the positioning quality will be improved by these specified optimal parameters.

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33

Shen, Chun-Sheng, and 沈椿勝. "Implementation of Precision Force Control for an Electro-hydraulic Servo Press Machine System." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/24938506703192438241.

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碩士
建國科技大學
電子工程系暨研究所
100
In this paper object is designing a PC-Based control system for an electro-hydraulic servo press machine system to realize precision force control. The key future is using a release pressure valve and a flow servo valve cooperated and a force sensor feedback to obtain hybrid pressure control. And using LabVIEW software designed fuzzy controller to obtain the hydraulic cylinder moving and output force precision control. Owing the hydraulic system can be accomplished small volume output high-power, such that it is used popularly to the industry. However, in the hydraulic system the oil is compressible and the system parameter variable can be affected by the oil temperature, the hydraulic servo system performances can be more affected by these disadvantages. We design a fuzzy controller to deal with this nonlinear and variable parameter hydraulic system to implement hydraulic cylinder position and force control performances. Through the constructed electro-hydraulic servo press machine system experimental testing, in the cases of step, multi-step, and sinusoidal force command inputs, the test results show that the proposed control scheme is capable of improving the tracking precision.

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34

Liu, Yuan-Liang, and 劉源良. "Model Reference Adaptive Control based on Neural Network for Electro-Hydraulic Servo System." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/tya53m.

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博士
中原大學
機械工程研究所
91
In this study, a novel adaptive control using multiple neural networks is proposed, which consist of neural controller, neural emulator and neural tuner, to control the swashplate angle of a variable displacement axial piston pump (VDAPP) with a three-way electro-hydraulic proportional valve (EHPV) and the position of an actuator with one electro-hydraulic servo valve (EHSV). The neural controller with specialized learning architecture utilizes the linear combination of error and its derivative to approximate the back propagation error (BPE) for weights update. The neural tuner adjusts the parameters of this linear combination. The nonlinear model of VDAPP and EHSV actuator were identified beforehand, and updated on-line by the neural emulator. The triple networks and the plant were integrated to an adaptive control system, which was designed by Lyapunov theorem for the guarantee of global stability. The simulation and experiment results showed that the time responses of control system with square commands of various amplitudes were stable and with fast convergent speed. The mean square error (MSE) of control process was smaller than those of the direct neural, indirect neural and neural tuner parameter controls.

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35

HSIAU, GWO-RONG, and 蕭國榮. "Application of fuzzy control to a hydraulic position servo system using proportional valve." Thesis, 1993. http://ndltd.ncl.edu.tw/handle/82180241863740178889.

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36

Chien-JungChen and 陳建融. "Development of a Servo Hydraulic System with a Self-tuning Fuzzy PID Controller." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/37747k.

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37

Cheng, Ping-Chang, and 陳秉昌. "A Study of High Precision Servo Position Control of Hydraulic System under Low Speed." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/07621367260372578613.

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碩士
國立成功大學
機械工程學系碩博士班
91
The study sets up a vertical hydraulic servo control system, and controls the positioning and tracking task of the hydraulic cylinder under low speed with a small flow servo valve. For the simulation of the load force in the experiment, in order to get the result of constant or variable load force, a pressure servo valve is used, which controls the pressure of the chamber of the load cylinder. About the nonlinearity of the hydraulic servo system, many papers in recent years used the linearization at the operation point or system identification to get the approximate linear mathematical model, and then design the controller according to the model. Also, some papers based on expert experience, applied the fuzzy controller design on this nonlinear system. This paper sets up a nonlinear mathematical model, and designs a controller using input-output linearization, then compares the results with traditional linear controller. From the observation of the experiment, the tracking performance and the disturbance rejection of nonlinear controller is better than traditional linear controller.

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38

劉士榕. "Limit cycle prediction for a hydraulic position servo system with valve-controled single-rod cylinder." Thesis, 1990. http://ndltd.ncl.edu.tw/handle/72853816235437974907.

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39

Chen, Po-Chi, and 陳柏祺. "Study on the Response Time for a Super High Speed Servo-Hydraulic System and Components." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/86pkcg.

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碩士
中原大學
機械工程研究所
91
Abstract This study is about the hydraulic servo system for the Super high-speed injection molding. The purpose of research is to study the key influence on characteristics of system response by measuring delay and reaction time under different processed setting during high speed injection. In this study, we utilized PID control by digital V/P control cards to understand the response characteristics of system. The human-machine interface was built by LabVIEW software to input the command and capture the feedback signals to calculate the delay time and reaction time of the high speed injection system. The results show that under speed closed-loop control, stable and stepping up the PID speed control, the response time increases as load and speed command increasing, but it decreases as hydraulic pressure increases. Actually, the influence factors of the hydraulic system were included electric components and hydraulic components. Different PID controllers influences the speed curve and response. The results of this study provide a better design rule and function for designers and operators to develop a super high-speed injection molding machine with hydraulic servo system.

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40

Li, Zong-lun, and 李宗倫. "Neural Network Self-Organizing Sliding Mode Fuzzy Controller Applied in Double-Axial Electro-Hydraulic Servo System." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/04597090811990253117.

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碩士
國立臺灣科技大學
機械工程系
101
Based on sliding mode fuzzy control theorem, this thesis designs sliding mode fuzzy controller, self-organizing sliding mode fuzzy controller and neural network self-organizing sliding mode fuzzy controller for applications of double-axial electro-hydraulic control system. The self-organizing sliding mode fuzzy controller provides a learning mechanism to modify the fuzzy rule table online. The neural network self-organizing sliding mode fuzzy controller adds a neural network to modify the defuzzification gain. Different experiments, including step and sinusoidal commands, are performed to compare their transient and steady state performances of the above three controllers. Experimental results reveal that the neural network self-organizing sliding mode fuzzy controller has fast transient response and excellent accuracy in step command experiment. In the low frequency fatigue experiment, experimental results indicate that these are no significant difference among these three controllers. However, in high-frequency fatigue experiments, the neural network self-organizing sliding mode fuzzy controller has more significant robustness and better accuracy than the sliding mode fuzzy controller and the self-organizing sliding mode fuzzy controller.

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41

Yang, Guo-Wei, and 楊國偉. "With Wireless Remote Control Technique to Implement of An Electro-Hydraulic Servo Precision Position Control System." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/46391190965491394106.

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碩士
建國科技大學
電子工程系暨研究所
102
In this paper object is designing a PC-Based control system for an electro-hydraulic servo press machine system to realize precision position control. The key future is using LabVIEW software designed discrete PID controller and discrete fuzzy controller to obtain the hydraulic cylinder moving control to realize precision position control. And, this project combined the wireless remote control technique and closed wrap transmission technique to realize remote control. However, in the hydraulic system the oil is compressible and the system parameter variable can be affected by the oil temperature, the hydraulic servo system performances can be more affected by these disadvantages, the proportional controller is difficult to achieve precision position control. The discrete controller has been designed to drive the servo valve shaft moving direction and opening the fluid hole area to implement hydraulic cylinder precision position control. However some workspace is very bad circumstances, people can’t manipulate on both sides of the machine. Using single-chip microcomputer with Xbee-PRO wireless communication module designed remote controller to realize the remote control. Whatever the remote control and the PC direct control, through the constructed electro-hydraulic servo press machine system experimental testing, in the cases of step, multi-step, sinusoidal, and repeat steps position command inputs, the test results show that the proposed control schemes have better tracking precision performance of the servo press machine.

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42

Yu, Chi-Yang, and 余啟揚. "A Study on the Regulating Response Characteristics of Hydraulic Servo System for the High-Speed Injection Molding." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/58633199246269207421.

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碩士
中原大學
機械工程研究所
90
Abstract This paper presents the study of hydraulic servo system for the high-speed injection molding. The purpose of research is study the influence of delay and reaction time to response characteristics of system. The methods of regulated injection speed collocate with and without melt load were addressed. In this study, we utilized PI control by analog and digital V/P control cards to understand the response characteristics of system. The human-computer interface through LabVIEW software was also developed to collect LVDT signal. In addition, to discuss the reason of effecting speed response through the HyPneu software simulation. The results show that under velocity closed-loop control, stable and stepping up the PI velocity control, the response time system will be quickly. On the other hand, large melt load will increase the response time. Moreover, under different velocity commands and V/P control cards, it can be seen that the maximum factor to affect delay time of system was initial velocity of spool. The results of this study provide a better design rule and function for designers and operators to develop a high-speed injection molding machine with hydraulic servo system.

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43

Shen, Shih-Tang, and 沈士棠. "Intelligent Parallel Control of Energy-Saving Control and Servo Control on a Hydraulic Valve-Controlled Cylinder System." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/33579955096288912335.

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碩士
國立臺灣科技大學
自動化及控制研究所
92
Conventional hydraulic valve-controlled systems with constant flow pump have better control response. Although supply pressure of pump of such systems is set by a relief valve according to the load of the hydraulic cylinder, the energy efficiency is lower. The objective of this research is to develop suitable controllers for combining servo control (i.e. path control, velocity control and force control) with energy-saving control (i.e. constant power control, load-sensing control and constant supply pressure control) in a hydraulic valve-controlled cylinder system so as to realize high energy efficiency and high servo control performance simultaneously. The integrated control system is a two-input two-output (TITO) system, that is composed of the servo control system and the energy-saving system. The coupling interaction exists in the complex integrated system such that decoupling compensators are used. Controllers of is integrated system were developed by fuzzy sliding mode control theory. Fuzzy sliding mode control theory is used for simplifying the complex fuzzy rule bases of the TITO system and guaranteeing the robustness and stability of fuzzy control systems. Furthemore, self-organizing modifiers are also used on the FSMC control for adapting the control rules according to the environment variation. The experimental results show that servo control, include path control, velocity control and force control, with load-sensing control can save energy substantially in comparison with the conventional system with relief valve and maintain excellent servo control performance. Thus the feasibility of the integration of servo control and energy-saving control on a hydraulic valve-controlled cylinder system is verified. Keywords: hydraulic valve controlled system, parallel control, load-sensing system, energy-saving control, servo control, decoupling control, fuzzy sliding mode control, self-organizing modifier.

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44

Tzu-HuaWang and 王子驊. "Design of an Adaptive Gain-Scheduling Fuzzy-PID Controller in Pressure Control of a Servo Hydraulic System." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/40205730923221696136.

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45

Wu, Ping-Ying, and 吳秉穎. "Development of a Hydraulic-Dual Piezoelectric Hybrid Servo Positioning System for Large Stroke High Loading and Nanometer Precision." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/20474045817057517623.

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碩士
國立臺灣大學
工程科學及海洋工程學研究所
96
The purpose of this thesis is to develop a hydraulic-dual piezoelectric hybrid positioning control system with bi-directional large stoke, high load, high response and high precision, in which the variable rotational speed hydraulic pump driving hydraulic cylinders combines dual piezoelectric actuators positioning system. Due to the structure limit of the stack type piezoelectric actuator, the piezoelectric actuator allows big compression force, but small tension force and torque. The dual piezoelectric positioning system developed in this paper makes the two piezoelectric actuators having only compression force for applying in bi-directional high loading condition. The hydraulic servo system serves to position in coarse range and the dual-piezoelectric positioning system works in fine range to reach nanometer range positioning accuracy. The control system contains dual-input and single output. For that, adaptive fuzzy controller with self-tuning fuzzy slide-mode compensation (AFT-STFSMC) is used to design the hydraulic position controller and the dual-piezoelectric positioning controller. To solve the coupling interaction between the two subsystems, a decoupling controller is added. The simulation and experiment results show that the proposed hydraulic-dual piezoelectric system can achieve 20 nm accuracy with the stroke of 300 mm and the max. loading of 130 kgf.

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46

Li, Mei-Tung, and 李梅東. "The Applications Of An Intelligent Fuzzy Weighted Input Estimation Controller To Control The Electrical And Hydraulic Servo System." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/10639790760621449410.

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碩士
國防大學理工學院
兵器系統工程碩士班
97
This work presents the applications of an intelligent fuzzy weighted input estimation controller to control the electrical and hydraulic servo system under the influence of unknown system variation and external interference maintain its high performance. This controller is composed of the adaptive fuzzy controller and the fuzzy weighted input estimation method. The adaptive fuzzy controller including the modification factor is mainly used to keep the system stable and prevent the system from vibrating. The robust fuzzy controller is the on-line estimation principle composed of the Kalman filter and the recursive least square estimator with the fuzzy weighting factor. By measuring the position and velocity of hydraulic strut and the pressure of hydraulic vessel, the displacement of valve shaft can be estimated. This method can be applied without using the stress sensors and can reduce the manufacturing cost. Besides, the system performance and adaptability can be enhanced. By simulating the parameters and comparing the simulation results with the ones using the adaptive fuzzy controller and the robust fuzzy controller, the method proposed in this paper can be verified to be capable of performing tracking rapidly and reducing the effects due to the noise under the influence of the environmental change. This method can resolve the control issue of the electrical and hydraulic servo within the weapon vehicle system by facilitating the readiness for firing and keeping the equipment balanced after the recoil force occurs.

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47

Chen, Cheng-Hong, and 陳承宏. "Design of Nonlinear Controllers of Precision Position Control and Power Saving Implement for a Hydraulic Servo Press Machine System." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/85243865623428267307.

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碩士
建國科技大學
電子工程系暨研究所
99
In this paper object, using Matlab/Simulink software designed PID controller, Fuzzy controller and Sliding mode controller for a hydraulic cylinder servo position system to realize precision position control and energy saving performance, and using LabVIEW software designed Fuzzy controller for hydraulic cylinder servo position system to realize precision position control and energy saving performance. The hydraulic system can be accomplished small volume output high-power, such that it is used popularly to the industry. However, in the hydraulic system the oil is compressible and the oil temperature can affect the system parameter variable, the hydraulic servo system performances can be more affected by these disadvantages. Therefore, the need of high precision position control in the hydraulic system can’t be fulfilled by using the traditional control methods, and the oil supply is fixed when hydraulic cylinder is reached position on the traditional of hydraulic control system, the hydraulic motor is full speed, it can be caused surplus of oil, the energy can be more waste by these disadvantage. In this paper, we design a fuzzy controller and sliding mode controller to deal with this nonlinear and variable parameter hydraulic system to implement hydraulic cylinder precision position control performances and control hydraulic motor speed by inverter to implement energy saving. Through the constructed electro-hydraulic servo press machine system experimental testing, in the cases of step and sinusoidal position command inputs, the test results show that the proposed control scheme is capable of improving the tracking precision and has a good energy saving by measured of power consumption.

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48

Chen, Chung-Chieh, and 陳宗傑. "THE RESEARCH OF NOVEL FLUID POWER SERVO SYSTEMS –High Response and High Efficiency Hydraulic Pump-Controlled System and High Precision Positioning Control of Pneumatic-Piezoelectric Hybrid System." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/82438195228679349401.

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博士
國立臺灣科技大學
自動化及控制研究所
97
Hydraulic systems have the advantages of high power-weight ratio, large driving forces, and high robustness. However, improving the response and energy-efficiency of hydraulic servo systems are essential problems. On the other hand, pneumatic systems have the advantages of high response, less expense and cleanliness. However, the non-linearity nature of pneumatic systems restricts positioning precision. Thus, this dissertation focuses on two researches: improving the response and energy-efficiency of hydraulic servo systems, and developing a high precision positioning control pneumatic systems. Part I of this dissertation develops an electro-hydraulic pump-controlled system for achieving high response and high energy-efficiency. The conventional hydraulic valve-controlled systems have high response but low energy-efficiency. Hydraulic pump-controlled servo systems have high-energy efficiency. However, the conventional pump-controlled systems have lower response. Therefore, this dissertation aims to develop a high response and high-energy efficiency electro-hydraulic pump-controlled system driven by a constant displacement piston pump with a variable rotational speed AC servomotor. Furthermore, the servo performance of the variable rotational speed pump-controlled system (VRS-PCS) is investigated experimentally in comparison with that of the variable displacement pump-controlled system (VD-PCS). A novel adaptive signed-distance fuzzy controller with self-tuning fuzzy sliding-mode compensation (ASDFC-STFSMC) is proposed for motion control of pump-controlled systems. The ASDFC-STFSMC combines the adaptive signed-distance fuzzy control with the self-tuning fuzzy sliding-mode control scheme. Thus, fuzzy rules can be reduced in number and adjusted automatically. Furthermore, the function approximation error of equivalent controller can be compensated for improving control performance. Subsequently, the motion controls of VRS-PCS and VD-PCS controlled by ASDFC-STFSMC are implemented respectively, which experimental results clarify that the VRS-PCS realizes the performance of both high response and high energy-efficiency. In addition, the performances of VRS-PCS are superior to that of VD-PCS in the motion controls. Part II of this dissertation investigates a novel pneumatic-piezoelectric hybrid positioning control system that contains a pneumatic cylinder and a piezoelectric actuator combined in cascade. The pneumatic cylinder positions with high speed and large strokes. The piezoelectric actuator positions in fine strokes to compensate for the influence of friction force. Thus, the pneumatic-piezoelectric hybrid control system can achieve large strokes, high response, and high positioning precision. The control strategies of the pneumatic-piezoelectric hybrid positioning control system are designed and verified in experiments using adaptive discrete variable structure controls (ADVSC) and decoupling self-organizing fuzzy sliding mode controls (DSOFSMC) in sequence. The ADVSC combines self-tuning adaptive controls and discrete variable structure controls, thus the control parameters can be adapted on-line to achieve an optimum sliding surface and reduce the chattering phenomenon of variable structure control. The DSOFSMC contains a self-organizing fuzzy sliding mode control (SOFSMC) and a decoupling controller. Thus, it can decrease the fuzzy rule numbers, on-line self-organize the fuzzy rules and on-line weight the two subsystems. Subsequently, the pneumatic-piezoelectric hybrid positioning control is implemented, which experimental results clarify that, the positioning precision of the pneumatic-piezoelectric hybrid system controlled by ADVSC can reach 0.1 μm with high response for the strokes of 10 mm and 180 mm. Furthermore, the pneumatic-piezoelectric hybrid system controlled by DSOFSMC can achieve positioning precision of 20 nm with high response for stroke of 250 mm.

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49

Chien, Yu-Wei, and 簡御偉. "Integration of Servo Control and Load-sensing Control on a Hydraulic Valve-controlled Cylinder System Using Fuzzy Sliding Surface control." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/73722473359539708705.

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碩士
國立臺灣科技大學
工程技術研究所自動化及控制學程
89
Electro-hydraulic valve controlled systems has better response, so they often are used in hydraulic servo control systems. However, in the traditional hydraulic valve-controlled system, supply pressure is set constant by a relief valve. The most serious disadvantage of such systems lies in the low energy efficiency. So electro-hydraulic load-sensing systems are used to improving the energy efficiency. Load-sensing systems adjust supply pressure depending on load-sensing pressure. The objective of the research project is to develop controllers to integrate the electro-hydraulic load-sensing system (ELS) and the hydraulic valve-controlled cylinder servo control system. Because the ELS is also a hydraulic valve-controlled cylinder control system, the overall control system is composed of the two valve-controlled hydraulic cylinder servo control systems and become a complex MIMO system. The control strategies are developed by fuzzy sliding surface theory (FSS) to improve the robust of the controllers. The sliding surface is used to simplify the complex rule base of the fuzzy controller. The self-organization modifier is also used on the FSS control to make the control rules adapting in accordance with the environment variation. The experiment results show that the integration of servo control and saving energy control e is available. The ELS saves more than 50% energy of the traditional hydraulic system with relief valve.

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50

Lee, Lian-wang, and 李聯旺. "Study of Integration of Servo Control and Energy-saving Control on a Hydraulic Value-controlled System Using H∞ Control with Genetic Algorithm." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/29493606573870672066.

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碩士
國立臺灣科技大學
工程技術研究所自動化及控制學程
89
ABSTRACT The objective of the research project is to develop an Electro-hydraulic Load-sensing System (ELS) used in a hydraulic valve-controlled cylinder servo control system. Because the ELS is also a hydraulic valve-controlled cylinder control system, the overall control system is composed of the two valve-controlled hydraulic cylinder servo control systems and become a complex MIMO system. For a hydraulic valve-controlled system, control system has better response if the supply pressure is higher. It has better performance and control accuracy. So, as the ELS adjusts the supply pressure of pump, the dynamic response of the working cylinder is influenced definitely. In this paper, Genetic Algorithm(GA) is used to solve -control problems by utilizing it to select the weighting function in -control formulation. This study proves the practicability of the integration of the electrical hydraulic loading sensing system and hydraulic valve controlled system at the same time. The experimental results reveal that the GA method can optimize the weighting functions in -control problems to get good feasibility and superiority. Key words：hydraulic valve-controlled system、load-sensing system、servo control、H-infinity theory、Genetic algorithm、velocity control、path control

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