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1
McCluskey, Emmet Gerard. "Rule-based automatic PID controller tuning." Thesis, Queen's University Belfast, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.335433.
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Chin, Hui Hui. "ALL DIGITAL DESIGN AND IMPLEMENTAION OF PROPORTIONAL-INTEGRAL-DERIVATIVE (PID) CONTROLLER." UKnowledge, 2006. http://uknowledge.uky.edu/gradschool_theses/272.
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Due to the prevalence of pulse encoders for system state information, an all-digital proportional-integral-derivative (ADPID) is proposed as an alternative to traditional analog and digital PID controllers. The basic concept of an ADPID stems from the use of pulse-width-modulation (PWM) control signals for continuous-time dynamical systems, in that the controllers proportional, integral and derivative actions are converted into pulses by means of standard up-down digital counters and other digital logic devices. An ADPID eliminates the need for analog-digital and digital-analog conversion, which can be costly and may introduce error and delay into the system. In the proposed ADPID, the unaltered output from a pulse encoder attached to the systems output can be interpreted directly. After defining a pulse train to represent the desired output of the encoder, an error signal is formed then processed by the ADPID. The resulting ADPID output or control signal is in PWM format, and can be fed directly into the target system without digital-to-analog conversion. In addition to proposing an architecture for the ADPID, rules are presented to enable control engineers to design ADPIDs for a variety of applications.
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Chopra, Shubham. "Evolved Design of a Nonlinear Proportional Integral Derivative (NPID) Controller." PDXScholar, 2012. https://pdxscholar.library.pdx.edu/open_access_etds/512.
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This research presents a solution to the problem of tuning a PID controller for a nonlinear system. Many systems in industrial applications use a PID controller to control a plant or the process. Conventional PID controllers work in linear systems but are less effective when the plant or the process is nonlinear because PID controllers cannot adapt the gain parameters as needed. In this research we design a Nonlinear PID (NPID) controller using a fuzzy logic system based on the Mamdani type Fuzzy Inference System to control three different DC motor systems. This fuzzy system is responsible for adapting the gain parameters of a conventional PID controller. This fuzzy system's rule base was heuristically evolved using an Evolutionary Algorithm (Differential Evolution). Our results show that a NPID controller can restore a moderately or a heavily under-damped DC motor system under consideration to a desired behavior (slightly under-damped).
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Chin, Hui Hui. "All digital design and implementation of proportional-integral-derivative (PID) controllers." Lexington, Ky. : [University of Kentucky Libraries], 2006. http://lib.uky.edu/ETD/ukyelen2006t00394/Thesis.pdf.
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Thesis (M.S.)--University of Kentucky, 2006.Title from document title page (viewed on March 28, 2006). Document formatted into pages; contains viii, 88 p. : ill. Includes abstract and vita. Includes bibliographical references (p. 85-87).
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Ramamurthi, Indu. "A versatile simulation tool for virtual implementation of proportional integral and derivative (PID) controllers." Thesis, Texas A&M University, 2003. http://hdl.handle.net/1969.1/5961.
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This thesis proposes an interactive software tool that can be used to compute complete sets of Proportional Integral Derivative (PID) Controllers from knowledge of the plant transfer function/frequency response data. This is based on research results and algorithms developed by Bhattacharyya and others. Until these research results were published, it was not known if a nominal system could be stabilized using PID Controllers, and current PID Controller designs are carried out using ad hoc tuning rules. By using simulations, engineers can best plan for and observe the stabilizing effect each of the variables has on system performance in a realistic environment. The software application developed calculates and optimizes complete stabilizing sets of PID Controllers for a rational Linear Time Invariant (LTI) system, and has been developed for analytical models of plants with and without time delay. Further, these PID Controller sets are optimized to project subsets simultaneously satisfying multiple performance index specifications. Sets of PID Controllers that stabilize a system are also calculated automatically from knowledge of the frequency response of the plant. It allows the user ease of design and the ability to customize the final solution while permitting full control over source parameters. This thesis includes an introduction to the algorithms that have been developed for plant stabilization, a complete description of the graphical user interface, the simulation of the algorithms performed using LabVIEW, and a summary of future work.
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Gogoi, Manoj. "Proportional-Integral-Derivative (PID) controller design for robust stability of arbitrary order plants with time-delay and additive uncertainty." Thesis, Wichita State University, 2010. http://hdl.handle.net/10057/3478.
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In the process control industry, majority of control loops are based on Proportional-Integral-Derivative (PID) controllers. The basic structure of the PID controllers makes it easy to regulate the process output. Design methods leading to an optimal and effective operation of the PID controllers are economically vital for process industries. Robust control has been a recent addition to the field of control engineering that primarily deals with obtaining system robustness in presences of uncertainties. In this thesis, a graphical design method for obtaining the entire range of PID controller gains that robustly stabilize a system in the presence of time delays and additive uncertainty is introduced. This design method primarily depends on the frequency response of the system, which can serve to reduce the complexities involved in plant modeling. The fact that time-delays and parametric uncertainties are almost always present in real time processes makes our controller design method very vital for process control. We have applied our design method to a DC motor model with a communication delay and a single area non-reheat steam generation unit. The results were satisfactory and robust stability was achieved for the perturbed plants.Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Electrical Engineering and Computer Science.
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Narasimhan, Bharat. "An automated virtual tool to compute the entire set of proportional integral derivative controllers for a continuous linear time invariant system." Texas A&M University, 2007. http://hdl.handle.net/1969.1/85831.
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This thesis presents the very practical and novel approach of using the Graphical User
Interface (GUI) to compute the entire set of Proportional Integral Derivative (PID)
controllers given the transfer function or the frequency response of the system under
consideration.
Though there is a wide spread usage of PID controllers in the industry, until
recently no formal algorithm existed on determining a set of PID values that will
stabilize the given system. The industry still relies on algorithms like the Ziegler-
Nicholas or ad-hoc approaches in determining the value of PID controllers. Also
when it comes to model free approaches, the use of Fuzzy logic and Neural network
do not guarantee stability of the system.
For a continuous Linear Time Invariant system Bhattacharyya and others have
developed an algorithm that determines the entire set of PID controllers given the
transfer function or just the frequency response of the system. The GUI has been
developed based on this theory. The GUI also evaluates the user input performance
specifications and generates a subset of stable controllers given the performance criteria for the system.
This thesis presents an approach of automating the computation of entire set of stabilizing Proportional Integral Derivative (PID) controllers given the system
transfer function or the frequency response data of the system. The Graphical User
Interface (GUI) developed bridges the gap between the developed theory and the
industry.
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Pereira, Kleber Batistela. "Projeto e desenvolvimento de uma unidade didática de apoio ao ensino da teoria clássica de controle PID." Universidade de Taubaté, 2012. http://www.bdtd.unitau.br/tedesimplificado/tde_busca/arquivo.php?codArquivo=566.
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Este trabalho foi concebido inicialmente através de projeto, montagem e ensaios preliminares de uma unidade analógica, para propósito didático, composta de um servomecanismo controlado pelas clássicas estratégias Proporcional, Integral e Derivativa (PID). Com este equipamento foi demonstrado os conceitos fundamentais da engenharia de controle com seus ensaios e medidas que permitem exemplificar, de forma simples e
bastante pedagógica, o funcionamento e os limites operacionais de um controlador prático. Os valores medidos em experimento foram comparados com valores obtidos pela simulação numérica de um modelo equivalente implementado no software MatLab. Utilizando-se da tecnologia PIC (Controlador de Interface Programável), o hardware analógico foi substituído, com a intenção de comparar os resultados para melhor ilustrar os abstratos conceitos da ação PID sobre um dispositivo eletromecânico razoavelmente linear. A unidade desenvolvida permite estabelecer um elo valioso à aprendizagem, buscando unir a teoria clássica, a simulação numérica, a aplicação digital e o comportamento real em uma situação física. Tivemos êxito nos resultados, conseguindo comprovar as modelagens matemáticas em aplicações práticas, além de poder comparar os desempenhos dos resultados analógicos com os resultados digitais.This work was initially conceived by design, assembly and preliminary tests of an analogic unit, for didactic purpose, composed of a servomechanism controlled by the classic strategies Proportional, Integral and Derivative (PID). With this device was demonstrated the fundamental concepts of control engineering and its trials and measures allow exemplify, in a simple and very interactive way, the functioning and the operational limits of a practical controller. The values measured in assay were compared with values obtained by numerical simulation of an equivalent model implemented in MatLab. By using the technology PIC (Programmable Interface Controller), the analogical hardware will be substituted, in order to compare the results to better explain the abstract concepts of the PID action over a sufficiently linear electromechanical device. The developed unit enables a valuable link to the learning, seeking to unite the classical theory, numerical simulation, digital application and real performance in a physical case. We were successful in results, obtaining proof of the mathematical models in practical applications, besides being able to compare the performances of analogic results with digital ones.
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Holgersson, Anton, and Johan Gustafsson. "Trajectory Tracking for Automated Guided Vehicle." Thesis, Linköpings universitet, Reglerteknik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-176423.
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The purpose of this thesis is to investigate different control strategies on a differential drive vehicle. The vehicle should be able to drive in turns at high speed and slowly when it should park next to a charger. In both these cases, good precision in both orientation and distance to the path is important. A PID and an LQ controller have been implemented for this purpose. The two controllers were first implemented in a simulation environment. After implementing the controllers on the system itself, tests to evaluate the controllers were made to imitate real-life situations. This includes tests regarding driving with different speeds in different turns, tests with load distributions, and tests with stopping accuracy. The existing controller on the system was also tested and compared to the new controllers. After evaluating the controllers, it was stated that the existing controller was the most robust. It was not affected much by the load distribution compared to the new controllers. However, the LQ controller was slightly better in most cases, even though it was highly affected by the load distribution. The PID controller performed best regarding stopping accuracy but was the least robust controller by the three. Since the existing controller has a similar performance as the LQ controller but is more robust, the existing controller was chosen as the best one.
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André, Simon. "Design and Optimization of Controllers for an Electro-Hydraulic System." Thesis, Linköpings universitet, Reglerteknik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-107620.
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Electro-Hydraulic (EH) systems are commonly used in the industry for applications that require high power-weight ratios and large driving forces. The EH system studied in this master thesis have recently been upgraded with new hardware components and as a part of this upgrade a new controller was requested. The system consists of a controller that computes a control signal for an electric motor. The motor drives a gear pump that generates a flow of hydraulic fluid. The flow is then directed to a cylinder. The movements of a piston in the cylinder is affected by the flow and the piston position can be measured. The measured piston position is then fed back to the controller and the control loop is complete. The system was previously controlled using a Proportional-Integral-Derivative (PID) controller and the purpose of this thesis is to compare the old controller with alternative control strategies suitable for this application. The evaluation of the controllers is based on both software and hardware simulations and results in a recommendation for final implementation of the best suited controller. The control strategies chosen for investigation are: a retuned PID controller, a PID controller with feed forward from reference, a PID based cascade controller, a Linear Quadratic (LQ) controller, and a Model Predictive Controller (MPC). To synthesize the controllers an approximate model of the system is formed and implemented in the software environment Matlab Simulink. The model is tuned to fit recorded data and provides a decent estimation of the actual system. The proposed control strategies are then simulated and evaluated in Simulink with the model posing as the real system. These simulations resulted in the elimination of the cascade controller as a possible candidate since it proved unstable for large steps in the reference signal. The remaining four controllers were all selected for simulation on the real hardware system. Unfortunately the MPC was never successfully implemented on the hardware due to some unknown compatibility error and hence eliminated as a possible candidate. The three remaining control strategies, PID, PID with feed forward from reference and the LQ controller, were all successfully implemented and simulated on hardware. The results from the hardware simulations compared to simulations made with the old controller, as well as the results from the software simulations, were then evaluated. Depending on the purpose one of two control strategies is recommended for this application. The LQ controller achieved the best overall performance and is presented as the control strategy best suited for this application.
11
Enbiya, Saleh A. "Automatic Control Strategies of Mean Arterial Pressure and Cardiac Output. MIMO controllers, PID, internal model control, adaptive model reference, and neural nets are developed to regulate mean arterial pressure and cardiac output using the drugs sodium Nitroprusside and dopamine." Thesis, University of Bradford, 2013. http://hdl.handle.net/10454/13421.
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High blood pressure, also called hypertension is one of the most common worldwide diseases afflicting humans and is a major risk factor for stroke, myocardial infarction, vascular disease, and chronic kidney disease. If blood pressure is controlled and oscillations in the hemodynamic variables are reduced, patients experience fewer complications after surgery. In clinical practice, this is usually achieved using manual drug delivery. Given that different patients have different sensitivity and reaction time to drugs, determining manually the right drug infusion rates may be difficult. This is a problem where automatic drug delivery can provide a solution, especially if it is designed to adapt to variations in the patient’s conditions.
This research work presents an investigation into the development of abnormal blood pressure (hypertension) controllers for postoperative patients. Control of the drugs infusion rates is used to simultaneously regulate the hemodynamic variables such as the Mean Arterial Pressure (MAP) and the Cardiac Output (CO) at the desired level. The implementation of optimal control system is very essential to improve the quality of patient care and also to reduce the workload of healthcare staff and costs. Many researchers have conducted studies earlier on modelling and/or control of abnormal blood pressure for postoperative patients. However, there are still many concerns about smooth transition of blood pressure without any side effect.
The blood pressure is classified in two categories: high blood pressure (Hypertension) and low blood pressure (Hypotension). The hypertension often occurred after cardiac surgery, and the hypotension occurred during cardiac surgery. To achieve the optimal control solution for these abnormal blood pressures, many methods are proposed, one of the common methods is infusing the drug related to blood pressure to maintain it at the desired level. There are several kinds of vasodilating drugs such as Sodium Nitroprusside (SNP), Dopamine (DPM), Nitro-glycerine (NTG), and so on, which can be used to treat postoperative patients, also used for hypertensive emergencies to keep the blood pressure at safety level.
A comparative performance of two types of algorithms has been presented in chapter four. These include the Internal Model Control (IMC), and Proportional-Integral-Derivative (PID) controller. The resulting controllers are implemented, tested and verified for three sensitivity patient response. SNP is used for all three patients’ situation in order to reduce the pressure smoothly and maintain it at the desire level. A Genetic Algorithms (GAs) optimization technique has been implemented to optimise the controllers’ parameters. A set of experiments are presented to demonstrate the merits and capabilities of the control algorithms. The simulation results in chapter four have demonstrated that the performance criteria are satisfied with the IMC, and PID controllers. On the other hand, the settling time for the PID control of all three patients’ response is shorter than the settling time with IMC controller.
Using multiple interacting drugs to control both the MAP and CO of patients with different sensitivity to drugs is a challenging task. A Multivariable Model Reference Adaptive Control (MMRAC) algorithm is developed using a two-input, two-output patient model. Because of the difference in patient’s sensitivity to the drug, and in order to cover the wide ranges of patients, Model Reference Adaptive Control (MRAC) has been implemented to obtain the optimal infusion rates of DPM and SNP. This is developed in chapters five and six.
Computer simulations were carried out to investigate the performance of this controller. The results show that the proposed adaptive scheme is robust with respect to disturbances and variations in model parameters, the simulation results have demonstrated that this algorithm cannot cover the wide range of patient’s sensitivity to drugs, due to that shortcoming, a PID controller using a Neural Network that tunes the controller parameters was designed and implemented. The parameters of the PID controller were optimised offline using Matlab genetic algorithm. The proposed Neuro-PID controller has been tested and validated to demonstrate its merits and capabilities compared to the existing approaches to cover wide range of patients.Libyan Ministry of Higher Education scholarship
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Enbiya, Saleh Abdalla. "Automatic control strategies of mean arterial pressure and cardiac output : MIMO controllers, PID, internal model control, adaptive model reference, and neural nets are developed to regulate mean arterial pressure and cardiac output using the drugs Sodium Nitroprusside and Dopamine." Thesis, University of Bradford, 2013. http://hdl.handle.net/10454/13421.
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High blood pressure, also called hypertension is one of the most common worldwide diseases afflicting humans and is a major risk factor for stroke, myocardial infarction, vascular disease, and chronic kidney disease. If blood pressure is controlled and oscillations in the hemodynamic variables are reduced, patients experience fewer complications after surgery. In clinical practice, this is usually achieved using manual drug delivery. Given that different patients have different sensitivity and reaction time to drugs, determining manually the right drug infusion rates may be difficult. This is a problem where automatic drug delivery can provide a solution, especially if it is designed to adapt to variations in the patient’s conditions. This research work presents an investigation into the development of abnormal blood pressure (hypertension) controllers for postoperative patients. Control of the drugs infusion rates is used to simultaneously regulate the hemodynamic variables such as the Mean Arterial Pressure (MAP) and the Cardiac Output (CO) at the desired level. The implementation of optimal control system is very essential to improve the quality of patient care and also to reduce the workload of healthcare staff and costs. Many researchers have conducted studies earlier on modelling and/or control of abnormal blood pressure for postoperative patients. However, there are still many concerns about smooth transition of blood pressure without any side effect. The blood pressure is classified in two categories: high blood pressure (Hypertension) and low blood pressure (Hypotension). The hypertension often occurred after cardiac surgery, and the hypotension occurred during cardiac surgery. To achieve the optimal control solution for these abnormal blood pressures, many methods are proposed, one of the common methods is infusing the drug related to blood pressure to maintain it at the desired level. There are several kinds of vasodilating drugs such as Sodium Nitroprusside (SNP), Dopamine (DPM), Nitro-glycerine (NTG), and so on, which can be used to treat postoperative patients, also used for hypertensive emergencies to keep the blood pressure at safety level. A comparative performance of two types of algorithms has been presented in chapter four. These include the Internal Model Control (IMC), and Proportional-Integral-Derivative (PID) controller. The resulting controllers are implemented, tested and verified for three sensitivity patient response. SNP is used for all three patients’ situation in order to reduce the pressure smoothly and maintain it at the desire level. A Genetic Algorithms (GAs) optimization technique has been implemented to optimise the controllers’ parameters. A set of experiments are presented to demonstrate the merits and capabilities of the control algorithms. The simulation results in chapter four have demonstrated that the performance criteria are satisfied with the IMC, and PID controllers. On the other hand, the settling time for the PID control of all three patients’ response is shorter than the settling time with IMC controller. Using multiple interacting drugs to control both the MAP and CO of patients with different sensitivity to drugs is a challenging task. A Multivariable Model Reference Adaptive Control (MMRAC) algorithm is developed using a two-input, two-output patient model. Because of the difference in patient’s sensitivity to the drug, and in order to cover the wide ranges of patients, Model Reference Adaptive Control (MRAC) has been implemented to obtain the optimal infusion rates of DPM and SNP. This is developed in chapters five and six. Computer simulations were carried out to investigate the performance of this controller. The results show that the proposed adaptive scheme is robust with respect to disturbances and variations in model parameters, the simulation results have demonstrated that this algorithm cannot cover the wide range of patient’s sensitivity to drugs, due to that shortcoming, a PID controller using a Neural Network that tunes the controller parameters was designed and implemented. The parameters of the PID controller were optimised offline using Matlab genetic algorithm. The proposed Neuro-PID controller has been tested and validated to demonstrate its merits and capabilities compared to the existing approaches to cover wide range of patients.
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Benigno, Tayara Crystina Pereira. "Modelagem matemática e controle de atitude e posição do quadrotor." Universidade Federal Rural do Semi-Árido, 2015. http://bdtd.ufersa.edu.br:80/tede/handle/tede/538.
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With advances in technology and the popularization of the use of Unmanned Aerial Vehicles (UAV's) so does the need to use more robust and more effective control techniques. Among the various types of unmanned aerial vehicles, this paper will focus on quadrotor model, which has a mechanical structure in the form of x, whose ends have an engine and propeller assembly, where the rotation of this group is responsible for the lift and the movements developed by quadrotor. This feeling, aiming to apply drivers that provide stability to the dynamic system. This study aims to conduct mathematical modeling using the Euler-Lagrange. With this, it is proposed a PID controller (Proportional Integral Derivative) to maintain stable the three orientation angles and height to a desired value. The development of the proposed controller will be validated via simulation confirming the application feasibility of the technique presented stability
Com o avanço tecnológico e a popularização do uso dos Veículos Aéreos Não Tripulados (VANT s) cresce também a necessidade do uso de técnicas de controle mais robustas e mais eficazes. Dentre os mais diversos tipos de veículos aéreos não tripulados, este trabalho irá focar no modelo do quadrotor, que possui uma estrutura mecânica em forma de cruz, cujas extremidades têm um conjunto de motor e hélice, onde a rotação desse conjunto é responsável pela força de sustentação e pelos movimentos desenvolvidos pelo mesmo. Objetivando aplicar controladores que proporcione estabilidade ao sistema dinâmico deste veiculo aéreo. O presente trabalho tem como objetivo realizar a modelagem matemática deste sistema usando as equações de Euler-Lagrange. Tendo isso, é proposto um controlador PID (Proporcional Integral Derivativo) para manter os três ângulos de orientação estáveis e a altura em um valor desejado. O desenvolvimento do controlador proposto será validado via simulação confirmando a viabilidade da aplicação da técnica de estabilidade apresentada
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Sá, Denis Fabrício Sousa de. "MODELOS BASEADOS EM REDES NEURAIS ARTIFICIAIS COM APLICAÇÃO EM CONTROLE INDIRETO DE TEMPERATURA." Universidade Federal do Maranhão, 2015. http://tedebc.ufma.br:8080/jspui/handle/tede/295.
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The representation of dynamic systems or plants via mathematical models occupies an important position in control system design that allow the performance evaluation of the controller during his development stage. These models are also used as an alternative to solve the problem of the hardness or impracticability to install sensors that measure the controlled variables, the dynamic systems representations enable non-invasive measurement of these variables. As consequence the designer has an alternative way to perform adaptive and optimal sensorless control for a given process. In this dissertation is presented a proposal for control systems schemas and algorithms, based on recurrent neural networks (ANN) and Box-Jenkins models, that are dedicated to sensorless or indirect control of dynamic systems. The proposed models and algorithms are associated with the systems identification and recurrent ANN approaches. The algorithms developed for the AAN training are Backpropagation Accelerated and RLS types that are compared with classical methods and strategies to obtain it online parameters of indirect control of system for a thermal plant, where the actuator is Peltier cell. The performance the parametric models of the plant and adaptive PID digital controllers and linear quadratic regulator (DLQR) that are the main elements of the sensorless temperature control system, are evaluated by means of hybrid simulations, where the algorithms implemented in micro controllers and the plant represented by mathematical models. The performance results of the proposed sensorless control algorithms are promissory, not only, in terms of the control system performance, but also due to the reexibility to deploy it in other dynamic systems.
A representação de sistemas dinâmicos ou plantas por meio modelos matemáticos ocupa uma posição relevante no projeto de sistemas de controle, permitindo que o projetista avalie o desempenho dos controladores durante a fase de desenvolvimento do projeto. Estes modelos também são utilizados para resolver o problema da dificuldade ou impossibilidade da inserção de sensores em plantas para medição de variáveis controladas, onde os modelos viabilizam a mediação não invasiva destas variáveis, fornecendo uma alternativa para realização do controle indireto adaptativo e ótimo de um dado processo. Nesta dissertação apresenta-se o desenvolvimento de modelos propostos baseados em redes neurais artificiais recorrentes para o controle sensorless ou indireto da planta. Os modelos propostos estão associados com as abordagens de Identificação de Sistemas e de RNA's recorrentes. OS algoritmos desenvolvidos para o treinamento das RNAs são do tipo Backpropagation acelerado e RLS, que são comparados com estratégias e métodos clássicos, para obtenção online dos parâmetros do sistema de controle indireto de uma planta térmica, tendo como atuador uma célula Peltier. Para uns de avaliação de desempenho do sistema de controle indireto da planta, os modelos paramétricos e controladores digitais adaptativos do tipo PID e regulador linear quadrático (DLQR) são avaliados por meio de simulações híbridas, sendo os algoritmos dos controladores implementados em microcontroladores e a planta representada por modelos matemáticos. Os resultados apresentados são promissores, não são sentido do desempenho do sistema de controle, mas também nos custos reduzidos para seu desenvolvimento, operação e flexibilidade de aplicação em outros sistemas dinâmicos.
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Feinauer, David Michael. "CONTROL CHARACTERISTICS OF AN ALL-DIGITAL PROPORTIONAL-INTEGRAL-DERIVATIVE (PID) COMPENSATOR." UKnowledge, 2011. http://uknowledge.uky.edu/ece_etds/3.
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The digitization of classical control systems presents a number of challenges and opportunities with respect to the miniaturization, distribution, reliability verification and obsolescence of both the controller and the underlying system under control. A method for the design of proportional-integral-derivative (PID) compensators realized in the form of all-digital components is presented. All-digital refers to a system implementation that is realizable with a wide range of digital logic components including discrete digital logic elements and programmable logic devices (PLDs) such as field-programmable gate arrays. The proportional, integral and derivative components of the classical PID control law were re-envisioned in terms of frequency of occurrences or counts for adaptation to combinatorial and sequential digital logic. Modification of the control scheme around this newly formed representation of system error enables the development of a PID-like FPGA-based or PLD-based controller. Details of the design of an all-digital PID-like controller including abstract, causal block diagrams and a MATLAB® and Simulink® based implementation are presented. The compensator was simulated in a velocity tracking DC motor control application and was found to perform comparably to that of a classical PID based control. Methods for assessing the resultant stability of an all-digital PID compensated system under control are discussed.
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Bhambhani, Varsha. "Optimal Fractional Order Proportional And Integral Controller For Processes With Random Time Delays." DigitalCommons@USU, 2009. https://digitalcommons.usu.edu/etd/246.
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This thesis developed a new practical tuning method for fractional order proportional and integral controllers (FO-PI) for varying time-delay systems like networked control systems (NCS), sensor networks, etc. Based on previously proposed FO-PI controller tuning rules using fractional Ms constrained integral gain optimization (F-MIGO), simultaneous maximization of the jitter margin and integrated time weighted absolute error (ITAE) performance for a set of hundred gain delay time-constant (KLT) systems having different time-constants and time-delay values are achieved. A multi-objective optimization algorithm is used to simultaneously maximize the ITAE factor and jitter margin of the plants at initial F-MIGO gain parameters. The new values of controller gain parameters are generalized to give a new set of optimal fractional order proportional integral (OFOPI) tuning rules such that the jitter margin and system performance of closed-loop KLT systems are maximized and yet the closed-loop feedback system is stable. This is further tested and verified by simulation techniques. Comparisons are made with other existing proportional integral derivative (PID) and fractional order proportional integral (PI) tuning rules to prove the efficiency of the new technique. It is further shown that OFOPI tuning rules perform better than traditional tuning methods for lag-dominated FOPDT systems, because it can take the varying time-delay better into account. The tuning method is modified to work with discrete-time controllers in the context of NCSs. Furthermore, experimental results in a NCS platform, Stand-alone Smart Wheel (omnidirectional networked control robot wheel), are reported using the tuning rules developed in this thesis. The optimization tuning method performed almost equally well in practice as in simulations. The thesis also shows that the tuning rule development procedure for OFOPI is not only valid for FOPDT systems but is also applicable for other general classes of plants which could be reduced to first order plant systems. Temperature control in heat flow apparatus and water-level control in a coupled tank system using FO-PI tuning rules are other major contributions of this thesis work.
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Jebelli, Ali. "Development of Sensors and Microcontrollers for Underwater Robots." Thesis, Université d'Ottawa / University of Ottawa, 2014. http://hdl.handle.net/10393/31283.
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Nowadays, small autonomous underwater robots are strongly preferred for remote exploration of unknown and unstructured environments. Such robots allow the exploration and monitoring of underwater environments where a long term underwater presence is required to cover a large area. Furthermore, reducing the robot size, embedding electrical board inside and reducing cost are some of the challenges designers of autonomous underwater robots are facing. As a key device for reliable operation-decision process of autonomous underwater robots, a relatively fast and cost effective controller based on Fuzzy logic and proportional-integral-derivative method is proposed in this thesis. It efficiently models nonlinear system behaviors largely present in robot operation and for which mathematical models are difficult to obtain. To evaluate its response, the fault finding test approach was applied and the response of each task of the robot depicted under different operating conditions. The robot performance while combining all control programs and including sensors was also investigated while the number of program codes and inputs were increased.
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Cong, Jun. "Enhancing TCP traffic flow performance with a proportional and integral rate controller: Theory, design, and performance evaluation." Thesis, University of Ottawa (Canada), 2004. http://hdl.handle.net/10393/26615.
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This thesis proposes a new network traffic congestion control algorithm---the PIR (Proportional and Integral Rate) controller. It is designed to overcome the shortcomings of RED and some other related AQM (Active Queue Management) techniques developed in recent years. That is to avoid unnecessary packet losses and stabilize the queue length in the router. It can also prevent the throughput reduction in the presence of wireless links. We proved the stability of the PIR controller theoretically and conducted the performance analysis and comparison for the PIR controller and some other common traffic congestion control schemes.
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Samaranayake, Lilantha. "Distributed control of electric drives via Ehernet." Licentiate thesis, KTH, Electrical Systems, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-1656.
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This report presents the work carried out aiming towardsdistributed control of electric drives through a networkcommunication medium with temporal constraints, i.e, Ethernet.A general analysis on time delayed systems is carried out,using state space representation of systems in the discretetime domain. The effect of input time delays is identified andis used in the preceding controller designs. The main hardwareapplication focused in this study is a Brushless DC servomotor, whose speed control loop is closed via a 10 MbpsSwitched Ethernet network. The speed control loop, which isapproximately a decade slower than the current control loop, isopened and interfaced to the network at the sensor/actuatornode. It is closed at the speed controller end at another nodein the same local area network (LAN) forming a distributedcontrol system (DCS).
The Proportional Integral (PI) classical controller designtechnique with ample changes in parameter tuning suitable fortime delayed systems is used. Then the standard Smith Predictoris tested, modified with the algebraic design techniqueCoefficient Diagram Method (CDM), which increases the systemdegrees of freedom. Constant control delay is assumed in thelatter designs despite the slight stochastic nature in thetiming data observations. Hence the poor transient performanceof the system is the price for the robustness inherited to thespeed controllers at the design stage. The controllability andobservability of the DCS may be lost, depending on the range inwhich the control delay is varying. However a state feedbackcontroller deploying on-line delay data, obtained by means ofsynchronizing the sensor node and controller node systemclocks, results in an effective compensation scheme for thenetwork induced delays. Hence the full state feedbackcontroller makes he distributed system transient performanceacceptable for servo applications with the help of poleplacement controller design.
Further, speed synchronizing controllers have been designedsuch that a speed fluctuation caused by a mechanical loadtorque disturbance on one motor is followed effectively by anyother specified motor in the distributed control network with aminimum tracking or synchronizing error. This type ofperformance is often demanded in many industrial applicationssuch as printing, paper, bagging, pick and place and materialcutting.
Keywords:Brushless DC Motor, Control Delay, DistributedMotion Control Systems, Proportional Integral Controller, SmithPredictor, Speed Synchronization, State Feedback Controller,Stochastic Systems, Switched-Ethernet, Synchronizing Error,Time Delayed Systems, Tracking Error
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Selby, Normajean. "STATE-VARIABLE FEEDBACK CONTROL OF A MAGNETICALLY SUSPENDED CENTRIFUGAL BLOOD PUMP." University of Akron / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=akron1185567515.
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Jebelli, Ali. "Design of an Autonomous Underwater Vehicle with Vision Capabilities." Thesis, Université d'Ottawa / University of Ottawa, 2016. http://hdl.handle.net/10393/35358.
Full textAbstract:
In the past decade, the design and manufacturing of intelligent multipurpose underwater
vehicles has increased significantly. In the wide range of studies conducted in this field, the
flexibility and autonomy of these devices with respect to their intended performance had
been widely investigated.
This work is related to the design and manufacturing of a small and lightweight
autonomous underwater vehicle (AUV) with vision capabilities allowing detecting and
contouring obstacles.
It is indeed an exciting challenge to build a small and light submarine AUV, while making
tradeoffs between performance and minimum available space as well as energy
consumption. In fact, due to the ever-increasing in equipment complexity and performance,
designers of AUVs are facing the issues of limited size and energy consumption.
By using a pair of thrusters capable to rotate 360o on their axis and implementing a mass
shifter with a control loop inside the vehicle, this later can efficiently adapt its depth and
direction with minimal energy consumption. A prototype was fabricated and successfully
tested in real operating conditions (in both pool and ocean). It includes the design and
embedding of accurate custom multi-purpose sensors for multi-task operation as well as an
enhanced coordinated system between a high-speed processor and accustomed
electrical/mechanical parts of the vehicle, to allow automatic controlling its movements.
Furthermore, an efficient tracking system was implemented to automatically detect and
bypass obstacles. Then, fuzzy-based controllers were coupled to the main AUV processor
system to provide the best commands to safely get around obstacles with minimum energy
consumption. The fabricated prototype was able to work for a period of three hours with
object tracking options and five hours in a safe environment, at a speed of 0.6 m/s at a
depth of 8 m.
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Jowkar, Saeid. "The Application of Programmable Logic Controller (PLC) to Control Temperature in Cold-room Based on TIA PORTAL Software." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2020.
Find full textAbstract:
A temperature sensor is a device to measure the temperature through an electrical signal. It requires a thermocouple or resistance temperature detectors (RTD) and will interface with a programmable logic controller (PLC). A temperature transmitter is a device that connects to a temperature sensor to transmit the signal elsewhere for monitoring and control purposes that its role is to convert the temperature sensor's signal to a 0-10V DC voltage in the PLC. The PLC voltage signal setting is compared to the temperature deviation after the Proportional Integral Derivative (PID) operation. Then, the system will issue a temperature control signal to achieve the cooling system voltage control so that it implements continuous monitoring and temperature control. The temperature control system in the industrial field has a certain value that it is an important factor for controlling temperature. A certain value of the temperature of the desired environment has to be set with a minimum and maximum set-point temperature which is suitable for that environment and the set-point value can be variable and can be changed with Human Machine Interface (HMI) easily.
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Catata, Elmer Osman Hancco. "Controlador PI FUZZY aplicado ao controle direto de potência do gerador de relutância variável de 12/8 conectado à rede elétrica." reponame:Repositório Institucional da UFABC, 2016.
Find full textAbstract:
Orientador: Prof. Dr. José Luis Azcue PumaDissertação (mestrado) - Universidade Federal do ABC, Programa de Pós-Graduação em Engenharia Elétrica, 2016.
Este trabalho apresenta o controle direto de potencia do gerador de relutancia variavel de 12/8 utilizando o controlador fuzzy PI auto-ajustavel e o controle vetorial do inversor conectado à rede eletrica. Inicialmente são estudados os principios de operação da maquina e a topologia do conversor eletronico de potencia que sera utilizado para aciona-lo. Usando o software de simulaçãoMatlab/Simulink é implementado o modelo da maquina de relutancia variavel utilizando as curvas caracteristicas, de corrente e torque, que foram extraídas utilizando dados experimentais. Utilizando o modelo da maquina é projetado o controlador de velocidade para sua operação no modo motor. Tambem sera projetado o controlador de potência PI utilizando o modelo estimado do sistema de conversão de energia eólica. A partir dos ganhos do controlador PI é projetado o controlador fuzzy PI autoajustavel com o objetivo de melhorar a resposta em regime permanente da potencia controlada. A potencia gerada pelo gerador de relutancia variavel é injetada à rede eletrica, atraves do controle independente das potencias ativa e reativa, para este proposito é utilizado um conversor trifasico de dois níveis. Na parte experimental deste trabalho foi implementado o controle de corrente por histerese para maquina operando no modo motor, posteriormente foi implementado o controle de corrente e controle da tens~ao no barramento CC para a máquina operando no modo gerador. Os resultados de simulação e experimentais se mostraram coerentes validando os controladores propostos.
This work presents the direct power control of the switched reluctance generator of 12/8 using the self-tuning fuzzy PI controller and the vector control for inverter connected to the grid. Initially, the machine's operating principles and the topology of the power electronics converter used to drive this machine are studied. The model of switched reluctance machine is implemented in Matlab/Simulink simulation software using the characteristic curves of current and torque extracted using experimental data. Using the machine's model, It is designed the speed controller for its operation in motor mode. Also, the PI controller is designed for the power control loop based on the estimation of the wind energy conversion system. Using the gains of the PI controller, It is designed the self-tuning fuzzy PI controller, in order to improve the steady state response of the power control loop. The power generated by the switched reluctance generator is injected into the power grid through the independent control of active and reactive power, for this purpose is used a three-phase two level converter. In the experimental part of this work was implemented the hysteresis current control for machine operating in motor mode, also, It was implemented the current and DC bus voltage control for the machine operating in generator mode. The simulation and experimental results were proved consistent and these results validate the proposed controllers.
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Guichaoua, Philippe. "Etude théorique, optimisation et simulation numérique d'un procédé de régulation thermique." Saint-Etienne, 1986. http://www.theses.fr/1986STET4006.
Full textAbstract:
Etude du dispositif de régulation sur une portion de frontière d'une région ouverte oméga du plan : ce dispositif comprend un régulateur PID dont le signal de commande est une mesure de différence de température. Possibilité d'un réglage optimal du régulateur pour une perturbation connue de la température initiale. Simulation numérique bidimensionnelle du fonctionnement
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Domanský, Ondřej. "Syntéza obvodových prvků s fraktální dynamikou." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2016. http://www.nusl.cz/ntk/nusl-241035.
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The first aim of this diploma thesis is to clarify problems with circuit elements described by the fractional-order dynamics, show their basic properties and possible applications in circuits with lumped parameters. The second topic is covering the synthesis of two-terminal devices which have different fractional-orders for requested phase shifts. For this kind of devices, the thesis also describes their optimization and approximation in the frequency domain and subsequent implementation in the form of passive ladder structures. The final part of diploma work will be focused on practical realization of universal fractional PID controller and the verification of proper function of this multi-port in various configurations to prove its correct function via real measurement of frequency and time responses.
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Hamiti, Karim. "Etude et mise en oeuvre de lois de commande numériques sur un actionneur électropneumatique avec frottements." Université Joseph Fourier (Grenoble), 1996. http://www.theses.fr/1996GRE10130.
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Le travail presente dans cette these est devolu a la realisation d'un actionneur electro-pneumatique a commande numerique. La reflexion conduite dans ce domaine avait un double objectif: ? d'une part, l'etude du systeme dans l'optique d'une commande par micro-controleur. Ceci nous a permis de revoir un ensemble de solutions possibles et d'en choisir la plus adequate, tout en gardant a l'esprit l'aspect implementation et le cahier des charges assigne. ? d'autre part, de tester experimentalement des algorithmes de commande lineaire robustes, sur un systeme electro-pneumatique fortement non lineaire. Cependant, nous avons constate que la presence du frottement de collage dans la partie mecanique du banc, a des consequences nefastes sur les performances statiques de l'asservissement. Pour resoudre ce probleme, nous avons propose une solution aisee a implementer, tout en conservant la methode de synthese du regulateur par placement de poles aussi bien que la structure du pid. Enfin, a la vue des resultats experimentaux, nous concluons que l'application des lois de commande lineaires basees sur une modelisation entree-sortie convient pour les verins pneumatiques de petites courses
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Cordero, Bautista Luis Gustavo. "Aplicação do algoritmo genético adaptativo com hipermutação no ajuste dos parâmetros dos controladores suplementares e dispositivo FACTS IPFC /." Ilha Solteira, 2019. http://hdl.handle.net/11449/182292.
Full textAbstract:
Orientador: Percival Bueno de AraujoResumo: As perturbações ou variações de carga produzem oscilações eletromecânicas que devem ser amortecidas o mais rápido possível para garantir confiabilidade e estabilidade da rede. Neste trabalho apresenta-se uma análise do dispositivo FACTS Interline Power Flow Controller (IPFC) e o controlador Proporcional Integral (PI) no gerenciamento dos fluxos de potência e a influência dos Estabilizadores do Sistema de Potência (ESP) e do IPFC Power Oscillation Damping (POD) sobre a estabilidade do sistema elétrico de potência. Neste trabalho enfoca-se nos estudos de estabilidade a pequenas perturbações usando um Algoritmo Genético Adaptativo com Hiper-mutação (AGAH) para ajustar os parâmetros dos controladores suplementares de amortecimento, o Estabilizador de sistema de potência (ESPs) e o Power Oscillation Damping (POD) em forma coordenada. O AGAH tem como objetivo encontrar os parâmetros ótimos do controlador para melhorar o amortecimento fraco das oscilações de baixa frequência locais e inter-área. Neste trabalho representa-se o sistema de elétrico de potência com a inclusão do dispositivo Interline Power Flow Controller com o modelo de sensibilidade de corrente (MSC). Considera-se como sistema teste o sistema Simétrico de Duas Áreas e o sistema New England como o intuito de avaliar o algoritmo proposto. As simulações são feitas no ambiente do MatLab. Por fim, apresenta-se a comparação do algoritmo genético com o desempenho do algoritmo proposto.
Abstract: Small-magnitude disturbances happen to produce electro-mechanical oscillations which should be damped as quickly as possible to ensure reliability and stability of the network. This work presents an analysis of Interline Power Flow Controller (IPFC) FACTS device and PI controller to control and manage power flow and also how Power System Stabilizers and IPFC Power Oscillations Damping (POD) controller influence over an electric power system stability. This work focuses on small-signal stability studies using an Adaptive Genetic Algorithm with Hyper-mutation (AGAH) in order to tune controller parameters in a coordinated way ensuring proper damping. AGAH aims to find optimal controller parameters to enhance the poor damping of local and inter-area low frequency oscillations. This works represents the electric power system and Interline Power Flow Controller device by a current sensitivity model (CSM). This paper considers two areas 14 bus symmetrical power system and New England power system in order to assess proposed algorithm. Coding and Simulations take place in MatLab platform. AGAH and GA get compared by time convergence and performance. This paper shows AGAH is an interesting optimization technique which outweighs GA.
Mestre
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Nkwanyana, Thamsanqa Bongani. "Multi-input multi-output proportional integral derivative controller tuning based on improved particle swarm optimization." Diss., 2021. http://hdl.handle.net/10500/27692.
Full textAbstract:
The PID controller is regarded as a dependable and reliable controller for process industry systems. Many researchers have devoted time and attention to PID controller tuning and they all agree that PID controllers are very important for control systems. A PID equation is very sensitive; its parameters must always be varied following the specific application to increase performance, such as by increasing the system’s responsiveness. PID controllers still have many problems despite their importance for control systems in industries. The problem of big overshoot on the conventional gain tuning is one of the serious problems. Researchers use the PSO algorithm to try and overcome those problems. The tuning of the MIMO PID controller based on the PSO algorithm shows many disadvantages such as high-quality control with a short settle time, steady-state error, and periodical step response. The traditional PSO algorithm is very sensitive and it sometimes affects the quality of good PID controller tuning.
This research has proposed a new equation for improving the PSO algorithm. The proposed algorithm is the combination of linearly decreasing inertia weight and chaotic inertia weight, after which a control factor was introduced as an exponential factor. This was very useful for simulations as it is adjustable. The Matlab simulation results of the experiments show that the simulations as it is adjustable. The Matlab simulation results of the experiments show that the new proposed equation converges faster and it gives the best fitness compared to linear inertia weight and oscillating inertia weight and other old equations. The MIMO PID controller system that consists of four plants was tuned based on the new proposed equation for the PSO algorithm (LCPSO). The optimized results show the best rise time, settling time, time delays, and steady-state compared to the systems that are tuned using the old equations. The exploration was directed at considering the impact of using the PSO calculation as an instrument for MIMO PID tuning. The results obtained in the examination reveal that the PSO tuning output improved reactions and can be applied to various system models in the measure control industry. The results for the MIMO PID controller tuned using PSO were assessed using integral square error (ISE), integral absolute error (IAE), and the integral of time expanded by absolute error (ITAE). The five well-known benchmark functions were also used to endorse the feasibility of the improved PSO and excellent results in terms of convergence and best fitness were attained.Electrical and Mining Engineering
M. Tech. (Electrical Engineering)
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Mendes, Carlos Hugo Ribeiro. "Robust Controller Design for an Autonomous Underwater Vehicle." Master's thesis, 2017. http://hdl.handle.net/10400.6/7956.
Full textAbstract:
Worldwide there has been a surge of interest in Autonomous Underwater Vehicles (AUV). The
ability to operate without human intervention is what makes this technology so appealing. On
the other hand, the absence of the human narrows the AUV operation to its control system,
computing, and sensing capabilities. Therefore, devising a robust control is mandatory to allow
the feasibility of the AUV.
Motivated by this fact, this thesis aims to present, discuss and evaluate two linear control solutions
being proposed for an AUV developed by a consortium led by CEiiA. To allow the controller
design, the dynamic model of this vehicle and respective considerations are firstly addressed.
Since the purpose is to enable the vehicle’s operation, devising suitable guidance laws becomes
essential. A simple waypoint following and station keeping algorithm, and a path following algorithms
are presented.
To devise the controllers, a linear version of the dynamic model is derived considering a single
operational point. Then, through the decoupling of the linear system into three lightly
interactive subsystems, four Proportional Integral Derivative controllers (PIDs) are devised for
each Degree Of Freedom (DOF) of the vehicle. A Linear Quadratic Regulator (LQR) design, based
on the decoupling of the linear model into longitudinal and lateral subsystems is also devised.
To allocate the controller output throughout the actuators, a control allocation law is devised,
which improves maneuverability of the vehicle. The results present a solid performance for
both control methods, however, in this work, LQR proved to be slightly faster than PID.É visível, a nível mundial, um aumento considerável do interesse em Veículos Autónomos Subaquáticos (Autonomous Underwater Vehicles - AUV). O que torna esta tecnologia tão atraente é a capacidade de operar sem intervenção humana. Contudo, a ausência do ser humano restringe a operação do AUV ao seu sistema de controlo, computação e capacidades de detecção. Desta forma, conceber um controlo robusto é obrigatório para viabilizar o AUV. Motivado por este facto, esta tese tem como objetivo apresentar, discutir e avaliar duas soluções de controlo linear, a propor a um AUV desenvolvido por um consórcio liderado pelo CEiiA. Para que o projeto do controlador seja possível, o modelo dinâmico deste veículo e respectivas considerações são primeiramente abordados. Com a finalidade de possibilitar a operação do veículo, torna-se essencial a elaboração de leis de guidance adequadas. Para este efeito são apresentados algorítmos de Waypoint following e Station keeping, e de path following. Para a projeção dos controladores é derivada uma versão linear do modelo dinâmico, considerando um único ponto operacional. Através da separação do modelo linear em três subsistemas são criados quatro controladores Proporcional Integral Derivativo (PID) para cada grau de liberdade (Degree Of Freedom - DOF) do veículo. É também projetado um Regulador Linear Quadrático (LQR), baseado na separação do modelo linear em dois subsistemas, longitudinal e lateral. É ainda apresentada uma lei de alocação de controlo para distribuir o sinal de saída dos controladores pelos diferentes atuadores. Esta provou melhorar a manobrabilidade do veículo. Os resultados finais apresentam um desempenho sólido para ambos os métodos de controlo. No entanto, neste trabalho, o LQR provou ser mais rápido do que o PID.
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Kumar, M. Prasanna. "Studies On Application Of Control Systems For Urban Water Networks." Thesis, 2008. http://hdl.handle.net/2005/874.
Full textAbstract:
Management and supply of water in an urban water distribution system is a complex process, which include various complexities like pressure variations across the network depending on topography, demand variations depending on customers’ requirement and unaccounted water etc. Applying automatic control methods to water distribution systems is a way to improve the management of water distribution. There have been some attempts in recent years to develop optimal control algorithms to assist in the operation of complex water distribution systems. The difficulties involved by these hydraulic systems such as non-linearity, and diurnal demand patterns make the choice of a suitable automatic control method a challenge. For this purpose, this study intends to investigate the applicability of different controllers which would be able to meet the targets as quickly as possible and without creating undue transients.
As a first step towards application of different controllers, PD and PID linear controllers have been designed for pump control and valve control in water distribution systems. Then a Dynamic Inversion based nonlinear controller has been designed by considering the non-linearities in the system. Here, different cases considering the effects of initial conditions used, linearization methods used, time step used for integration and selection of gains etc., have been studied before arriving at best controller. These controllers have been designed for both the flow control problems and level control problems. It is found that Dynamic Inversion-based nonlinear controller outperforms other controllers.
It is well known that the performance of controllers is much dependent on the tuning of the gains (parameters). Thus in this study various alternative techniques such as Ziegler--Nichols rules (ZNPID), Genetic algorithms (GAPID) and fuzzy algorithms (FZPID) have been studied and a comparative study has been made Although with all the three gain tuning methods, required states have reached their target values, but the responses vary much in reaching to final targets. The self-tuned FZPID controller outperforms other two controllers, especially with regard to overshoots and the time taken to tune the gains for each problem.
Further, an optimal DI controller is developed for the over determined case with more controls and less targets. Energy loss is considered as an objective function and normal DI controller equations are considered as constraints. Hence, an attempt is made to reduce the energy minimization in water distribution system by formulating an optimal control problem using optimal Dynamic Inversion concept.
Finally, leakage reduction model is developed based on excessive pressure minimization problem by locating valves optimally as well as by setting valves optimally. For this purpose, optimization problem is solved using Pattern search algorithms and hydraulic analysis is carried out using EPANET program.
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Lee, Ping-Hui, and 李炳輝. "Using Grey Proportional Integral Controller forPrecision Time Synchronization Protocol." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/17532358044805043883.
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碩士國立臺灣大學
電機工程學研究所
96
IEEE1588 standard is a precision time synchronization protocol (PTP). It is designed to synchronize real-time clocks in the nodes of a distributed system that communicate using a network. Within a subnet, the PTP system is expected to achieve the synchronization accuracy in sub-microsecond range. Thus, it is applicable to traditional measurement and control systems, industrial automation systems, communication systems, electrical power systems and many other areas of modern technology.The unit of clock servo plays important roles in the PTP system. It is usually implemented by proportional integral (PI) controller. The time offsets between the master and the slave clock are fed into the PI controller. The output of the PI controller is used to steer the slave clock to synchronize with the master clock. Therefore, the relative tick-rate of the slave clock can be stabilized. In order to improve the performance of the PI controller, this study adopts the gray theory to determine the parameter of the proportional term of the PI controller. The drift of the time offset from master clock can be obtained by using the gray prediction algorithm. Accordingly, the gray PI controller makes the system reduce the time to reach steady state. To assess the performance of the system, this study integrates the PTP software and the network interface with timestamper to establish a subnet. For the stability analysis of the system under tests, this paper utilizes the ITU-T recommended Allan deviation. Experimental results show that the performance of the gray PI controller is better than the traditional one. The transient response time of the system is significantly reduced by introducing the proposed gray PI controller.
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Li, Huang-Yi, and 李皇儀. "Applied Particle Swarm Optimization Algorithms to Parameters Tuning of Digital Proportional - Integral Controller." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/30502467646046001582.
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碩士龍華科技大學
工程技術研究所
99
PID controller can be divided into traditional PID and digital PID. The latter is consisted in the time series form. In this paper, applied Particle Swarm Optimization algorithm to parameters tuning of the digital PI controller, and compared with the Weighting Ziegler – Nichols (Z-N) algorithm. Particle Swarm Optimization algorithm uses a continuous iterative method to optimize, as genetic algorithm. Particle Swarm Optimization only processes the optimal solution and refreshing formula. It is easier than those steps of genetic algorithm. So, in the reasonable searching range, the speed of searching optimal solution of Particle Swarm Optimization algorithm is more quick than that of genetic algorithm. The paper uses permanent magnet synchronous motor as a controlled plant. The simulation program uses Matlab software. Simulation results confirm that the Particle Swarm Optimization applied to parameters tuning of the digital PI controller is better than weighted Z-N PI controller.
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Liao, Kuo-Yuan, and 廖國淵. "Design of a Single-Phase Inverter using Trapezoidal Integration-Based Proportional Integral Derivative Controller." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/2vsau7.
Full textAbstract:
碩士義守大學
電機工程學系
103
Traditional PID (proportional-integral-derivative) controllers have been broadly applied to single-phase inverters due to their simple structures and easy designs. Yet, the integral term of traditional PID controllers is based on rectangular integration. If the load of the inverter is highly non-linear, the precision of calculations will be low, and there will be steady-state errors. This thesis proposed a PID controller based on trapezoidal integration. Unlike rectangular integration, trapezoidal integration does not underestimate the error area, which can further result in calculation errors. Thus, the proposed single-phase inverter can achieve low total harmonic distortion (THD) output voltage and fast dynamic response. The problem with inverters using traditional PID controller of possible tracking errors in cases with highly non-linear loads can be resolved. To verify the effectiveness of the proposed controller, this thesis used the software MATLAB to run simulations. And the results showed that the AC output voltage of the proposed single-phase inverter is of high quality in any case with resistive load, step load change, or non-linear load.
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Jheng, Hao-Yi, and 鄭浩逸. "An Adaptive Proportional-Integral Controller for Power Management of 3D Graphics System-On-Chip." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/aw3jbr.
Full textAbstract:
碩士國立中山大學
資訊工程學系研究所
97
In the past few years, due to the rapid advance in technology and the aid of 3D graphics applications the world of 3D graphics is rapidly expanding from desktop computers and dedicated gaming consoled to handheld devices, such as cellular phones, PDAs, laptops etc.,. However, unlike traditional desktop computers and gaming consoles, mobile computing devices typically have slower processors that have less capability for handling large computation-intensive workloads like 3D graphics application. In addition, the power consumption is one of the major design specifications to realize the 3D graphics accelerating engine for mobile devices because handheld batteries have limited lifetimes. Moreover, the size of chip is depend on the Moore’s Law: The number of transistors in a chip are double in every eighteen months. Even though the produce cost is decrease, but the capacity of battery cannot increase like the transistors. Therefore, how to reduce power consumption by using efficient power management techniques has become a very important research topic in 3D graphics SoC design. For 3D graphics applications, dynamic voltage and frequency scaling (DVFS) is a good candidate to reduce the power consumption of 3D graphics accelerating engine. So many relative papers have researched in how to accurately predict the workload and scale the voltage and frequency. The prediction policy can divide into History-based predictor [1] and Frame-structure predictor [2-4]. The History-based predictor predicts the latter frame workload by previous frame workload to scale the voltage, and the frame-structure predictor performs offline and then determine the different kind of frame for an application. A table is used to save the mapping of different kind of frame to the voltage, and then the voltage is scaled according to the mapping table. A lot of researchers put the power management policy in software i.e. processors, but our proposed workload prediction scheme has been realized into the hardware circuit. Therefore, it can not only reduce the overhead of processor but also quickly adjust the voltage and frequency of 3D graphics accelerating engine. Our prediction policy is one of the History-based predictor ,and it is an adaptive PID predictor [5-6] in which the parameters of Proportional controller and Integral controller can be adaptively adjusted so that it can obtain more accurate prediction results than non-adaptive predictor. In general, the workload that the selected voltage can handle is usually over than the predicted workload. That is, actual workload is usually less than predicted workload. So that the slack time will be generated. We can utilize the slack time through Inter-frame compensation [7-10] to save more energy while maintaining the similar output quality. We use a simple policy to adaptively select the parameters for compensation between the frames to simplify the hardware architecture of the power management policy. Experimental results show that, we can get more energy saving and more accurate workload prediction when the adaptive PI predictor and adaptive Inter-frame compensation are utilized.
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Chen, Chih-Hao, and 陳志豪. "Dynamically Adjusted Proportional-Integral Technology in Servo Speed Mode for Roll-to-Roll Controller." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/72102580678738095726.
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碩士逢甲大學
資訊電機工程碩士在職專班
104
In this study, the application of the R2R (roll to roll) tension control of the speed, capability and stability is proposed. The system is based on proportional - integral compensation control the servo motor speed to obtainfixed speed and tension. In the control system architecture, consists of unwinding system, fixed speed system, and winding system. Systems begin with plastic bag lamination off axis tension, each independent tension detection device can individually feedback. In addition to fixed speed systems, winding and rewinding system because there are roll diameter changes, so roll diameter calculation can be applied to obtain the line speed. Tension detection and feedback units use a proportional - integral servo motor speed adjustment of the system to get a high stability of tension and speed control. Traditional control method is via the AD / DA module feedback tension value changes with severally servo motor torque control mode to reach a certain tension. This study proposed proportional - integral pre-integrated system to compensate servo motor speed and precise diameter calculation to obtain higher and more precise control accuracy and stability.
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徐德君. "Fuzzy Proportional-Integral Control on Automatic Gain Controller Design for the Wireless Local Area Networks." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/30337529838349966052.
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碩士國立中興大學
電機工程學系
91
This thesis aims at the automatic gain controller (AGC) design for a IEEE 802.11b baseband processor receiver. We propose Fuzzy PI control strategy to regulate the amplitude of the input signal to the baseband A/D converter. The operational delay and the system convergence are analyzed through a software package Synopsys and FPGA emulators Altera FLEX10K50E. Robustness and fault tolerance are verified through experimental results.
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Chuang, Chih-Hsien, and 莊志賢. "Design of Proportional Integral Derivative Controller with Feedforward Control and Dead Zone for PWM Inverters." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/s59srs.
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碩士義守大學
電機工程學系
103
Traditional proportional-integral-derivative (PID) controllers have been broadly applied to pulse-width modulation (PWM) inverters due to their simple structures and easy designs. However, traditional PID controllers are sensitive to parameter changes and load interferences. This fact may result in high total harmonic distortion (THD) and slow dynamic response in cases with an inverter of highly non-linear load. Thus, this thesis proposes a (PID) controllers with feedforward control and dead zone. With the dead zone PID controller, the sensitivity to large parameter changes and highly non-linear load can be reduced. And the feedforward control can enhance dynamic response, that in cases with an inverter of highly non-linear load, there can be low THD and fast dynamic response. To verify the effectiveness of the proposed controller, this thesis used the software MATLAB to run simulations. And the results showed that the proposed inverter can achieve low THD and fast dynamic response in cases with non-linear load.
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Lin, Yenku, and 林彥谷. "Design and Implementation of Modified Proportional Integral Derivative Controller with Differential Forward for DC-AC Inverters." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/56116073130236878859.
Full textAbstract:
碩士義守大學
電機工程學系
101
Due to simple structure and good dynamic property, Differential forward PID (DFPID) controller is widely used in DC-AC inverters control. However, the conventional DFPID controller is difficult to inhibit the disturbance of output signal, thus causing the deterioration of the inverter performance. In order to inhibit the disturbance of output signal and enhance the system robustness, a modified differential forward PID (MDFPID) controller for the DC-AC inverter design is proposed in this thesis. The performances of the DC-AC output are low total harmonic distortion, and fast dynamic response under linear and non-linear loading. In addition to retaining the advantages of simple structure and good dynamic property as the conventional DFPID controller, the MDFPID controller has also allowed easy adjustment of control parameters and significant inhibition of disturbance of output signal. To verify the effectiveness of this proposed controller, the Psim software is used to simulate the inverter and the experiment is also realized with digital signal processor. Finally, a high-quality AC output voltage can be obtained under non-linear loading.
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Zhan, Xun Xain, and 詹勳賢. "A Hybrid Particle Swarm Optimization / Proportional Integral controller for the Low Earth Orbit Satellite Tracking System." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/36628114084058869344.
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碩士國立高雄應用科技大學
電子工程系碩士班
101
The purpose of this thesis is to develop an intelligent algorithm of control system to track low-orbit satellites. Satellite tracking methods rely on SGP4 orbit forecasting model generated by the antenna pointing database and follow the point coordinates to command the rotation of the axes. Gears rotation gap will affect the strength of the received signal. The PI controller can adjust the error values caused by the drive shaft mechanism. Particle swarm optimization has fewer parameter settings and the advantages of fast convergence used for parameter optimization and variable selection. And particle swarm optimization algorithm can be used to search for the PI controller parameters, k_p and k_i. In the search process using resolver feedback mechanism of actual angle indicator as a basis to judge the fitness value of pros and cons. The experimental results demonstrate the reliability of proposed system and the function of program track mode.
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Chang, Chin-Ping, and 張進評. "DESIGN OF A HYBRID FUZZY LOGIC PROPORTIONAL PLUS INTEGRAL-DERIVATIVE CONTROLLER FOR A CLASS OF NONLINEAR SYSTEMS." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/02072317454608048046.
Full textAbstract:
碩士大同大學
電機工程學系(所)
93
In this thesis, we used PID-type controller as the foundation, to develop a hybrid fuzzy logic proportional term plus conventional integral and derivative terms (FUZZY P+ID) controller for improving the control response. This kind of controller is constructed by using an incremental fuzzy logic controller in place of the proportional term in the conventional PID controller. This thesis basic principle of this study is to reduce the parameters of a fuzzy controller to be tuned so that, in comparison with the PID-type controller, only one additional parameter should be adjusted. Using conventional PID controller, however, it is difficult to achieve a desired tracking control performance since the dynamic equations of a plant for the manipulator are tightly coupled, highly nonlinear and uncertain. In order to improve the tracking control performance under uncertainty, we propose a new hybrid control scheme for the nonlinear plants, which consists of a fuzzy logic proportional controller and a conventional integral and derivative controller (FUZZY P+ID). Finally, detailed numerical design processes and simulation results are performed to illustrate the effectiveness of the proposed scheme.
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Liu, Jin-Wei, and 劉晉瑋. "Design of a Feedforward Variable Integral Parameter PID Controller and Its Application to UPS Inverters." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/khkr5w.
Full textAbstract:
碩士義守大學
電機工程學系
103
Conventional PID controllers have been broadly applied to UPS inverters due to their simple structures and easy designs. Although in the case with linear load, conventional PID controllers can achieve good dynamic and steady-state response. However, in the case with highly non-linear load, steady-state errors will occur, and tracking control may not be precise, thus leading to high total harmonic distortion (THD) and slow dynamic response of inverter output voltage. Thus, this thesis proposes a PID controller with feedforward variable integral parameter. In the case with large parameter variation or highly non-linear load, the goal of zero steady-state error of the system can be led by adjusting the integral parameter. Furthermore, the feedforward control is used to improve the system’s tracking control capability, resulting in high quality of the output AC voltage of the inverter. The simulation result shows the validation of the proposed controller. For comparison purpose, this thesis also shows conventional PID controlled UPS inverter so that the high performance of the proposed controller can be verified.
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Wang, Hung-Kai, and 王宏鍇. "A Dynamic Adjusted Proportional-Integral Controller for Semiconductor Manufacturing and an Empirical Study of Critical Dimension and Overlay Errors." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/64556414674496491360.
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碩士國立清華大學
工業工程與工程管理學系
98
Semiconductor industry and its products change fast with time. There are about 300 to 500 processes in semiconductor manufacturing, and there are many factors affecting each process. Therefore, it is hard to estimate the input-output model for one process, and also hard to estimate the process disturbance distribution or model. However, in most of fabs in semiconductor industry, they use EWMA controller to control the process, which cannot adjust the control parameter with process disturbance. This research considers the situation that it is hard to estimate the process disturbance model, and propose a framework for the Dynamic Adjusted Proportional-Integral (DAPI) controller. By adjusting the control parameters lot by lot, we can effectively solve the problems mentioned above. And we will illustrate an empirical study of critical dimension control and overlay errors reduction of photolithography, both consider the time series disturbance model and real process disturbance. We will compare the output result with traditional EWMA (Exponentially Weighted Moving Average) controller, and show that DAPI controller can make the process closer to target and reduce the process output variance than EWMA controller. In addition, in real semiconductor manufacturing situation, there exists process sudden Shift and metrology Delay problems, which make the controller performs worse. Since DAPI controller adjusts input value slowly, it will not be affect by process sudden Shift. We will show that DAPI controller can solve those problems, and can be used to a real semiconductor manufacturing situation. Finally, in the real process disturbance situation, for critical dimension control, DAPI can improve 10% on Process Capability Ratio and improve 11% on process standard deviation. Also, for overlay errors reduction, DAPI can improve 16% on Range and improve 11% on root Mean squared error. For all scenarios and two real problems, DAPI can perform better than EWMA controller.
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Matos, Bruno Guilherme Gonçalves de. "Controlador e accionador para motor DC em malha fechada." Master's thesis, 2008. http://hdl.handle.net/1822/65413.
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Dissertação submetida à Universidade do Minho para obtenção do grau de Mestre em Electrónica Industrial e ComputadoresOs motores CC (corrente contínua) têm actualmente como principal aplicação a motorização de plataformas móveis, onde a fonte de energia é feita com o recurso a baterias. O controlo da velocidade de rotação destes motores vinha a ser feito com recurso a reóstatos variando a corrente do estator, sendo um processo eficaz no caso em que a carga e velocidade de rotação variem pouco. Com o desenvolvimento da electrónica surgiram controladores de velocidade, com gamas de variação de velocidade elevadas, fazendo compensações às flutuações de carga. O presente trabalho, trata do projecto e implementação de um controlador e accionador em malha fechada, para aplicação em motores DC (direct current), fazendo com que estes rodem a uma velocidade desejada, independente da carga aplicada. É feito um estudo do mercado, seleccionando alguns dos controladores existentes e analisando se o projecto actual é uma solução necessária para os objectivos pretendidos. Seguido do projecto completo, desde a análise topológica das estruturas escolhidas até a concepção de toda a electrónica necessária (accionadores, sensores, barramentos de dados e protecções), referindo os cuidados tidos no desenho do PCB (Printed Circuit Board). Na fase de projecto, é focado o estudo a várias técnicas de controlo em malha fechada, indicando o porquê, da técnica escolhida. É descrito todo software utilizado e programado, desde a linguagem de programação e compiladores utilizados até aos algoritmos realizados para o software desenvolvido. No final é apresentado o protótipo construído em laboratório e resultados alcançados, tendo como referência os objectivos pretendidos.
DC (Direct Current) motors have nowadays as main application the drive of mobile platforms, where the energy source comes from batteries. These motors rotation speed control was carried out using rheostat varying the stator current, being an efficient process when the load applied and rotation speed have little variation. With the actual electronics development speed controllers came up, with a high ranges of speed changes, compensating load changes. The present work, develops the implementation of a controller in a closed loop, to be used in DC motors, allowing them to rotate at a certain speed and completely independent of the load applied. A market survey is carried out, selecting some of the existing controllers and analyzing if the actual project is a desired solution to the defined objectives. After completing the project, from a topological analysis of the chosen structures up to the conception of the required electronics (drives, sensors, data bus and electronic protections), referring the care taken on the PCB (Printed Circuit Board) drawing. On the design phase, several closed loop control techniques were studied, pointing out the chosen technique. All the used and developed software is described, from the programming language to the used compilers, up to the developed algorithms for this project. In the end a prototype is developed, built up and presented, as well as the achieved results, having as reference the objectives stated for the project.
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Fernandes, Pedro Nuno Lopes. "Feedback-error learning control for powered assistive devices." Master's thesis, 2019. http://hdl.handle.net/1822/64777.
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Dissertação de mestrado integrado em Engenharia Eletrónica Industrial de ComputadoresGait pathologies often produce abnormal gait patterns, affecting human mobility. Powered assistive devices, such as lower-limb exoskeletons and orthoses, are starting to complement gait rehabilitation, to actively aid or restore the abnormal gait pattern. The human motor control system starts to influence the design of bioinspired architectures for these devices, comprising the definition of distinct levels of controllers (high-, mid-, and low-level) distributed hierarchically. Low-level controllers play an important role in this architecture, ensuring time-effective assistance adaptive to user’s needs as gait speed and trajectory. The main goal with this dissertation is the development of a real-time Feedback-Error Learning (FEL) low-level control to be integrated into a bioinspired control architecture approached in a Stand-alone, Active Orthotic System - SmartOs. The FEL control was performed by means of an Artificial Neural Network (ANN) as a feedforward controller to acquire the inverse model of the assistive device, and a Proportional-Integral-Derivative (PID) feedback controller to guarantee stability and handle with disturbances. A Powered Knee Orthosis and Powered Ankle-Foot Orthosis were used as the assistive devices and a positionbased tracking assistive strategy was applied. A validation without human load and with two subjects walking in a treadmill at 0.8, 1.0 and 1.2 km/h with the two assistive devices, controlled by the Feedback-Error Learning control, was performed. The ANN took around 90 s to learn the inverse model of the assistive device, demonstrating versatility and steadiness when changes to the magnitude and speed of the input trajectory were applied. The feedback controller guaranteed stability and shown good reactions to the applied disturbances. The implemented FEL control was capable to decrease the angular position error by 15% and to eliminate 0.25 s of phase delay when compared to a solo PID controller. Thus, it proves to be a time-effective asset to control assistive powered devices. Future work addresses the validation with more subjects and different assistive strategies.
Patologias da marcha podem conduzir ao desenvolvimento de uma marcha anormal, afetando a mobilidade das pessoas. Dispositivos ativos de assistência (DAA) começam a complementar a reabilitação da marcha. Particularmente, exosqueletos ou ortóteses ativas para os membros inferiores, destacam-se na área da reabilitação da marcha. O sistema de controlo motor humano tem sido usado como inspiração para o design de arquiteturas de controlo para estes DAA, pois compreendem a definição de diferentes níveis de controladores (alto, médio e baixo) organizados hierarquicamente. Especificamente, os controladores de baixo nível têm um papel importante nesta arquitetura, devendo garantir uma assistência temporalmente eficaz adaptada às necessidades do utilizador do utilizador, como a velocidade e a trajetória da marcha. O objetivo desta dissertação é o desenvolvimento do controlo de baixo nível Feedback- Error Learning (FEL) em tempo real, inserido no sistema de controlo bioinspirado SmartOs. O controlo FEL foi realizado através de redes neuronais artificias (RNA) como um controlador de realimentação positiva para adquirir o modelo inverso da planta, e um controlador Proporcional-Integral-Derivativo (PID) como controlador de realimentação negativa, para garantir estabilidade e lidar com perturbações do sistema. Uma ortótese ativa do joelho e do tornozelo foram os DAA usados e foi aplicada uma estratégia de assistência por seguimento baseado em posição. Foram efetuadas validações sem carga e com dois sujeitos a caminhar numa passadeira a 0.8, 1.0 e 1.2 km/h, com os dois DAA, separadamente, controlados pelo controlo FEL. A RNA demorou cerca de 90 s a aprender o modelo inverso do DAA, demostrando versatilidade e estabilidade quando foram aplicadas mudanças na magnitude e velocidade da trajetória de entrada. O controlador de realimentação negativa garantiu estabilidade e conseguiu corrigir o erro quando aplicadas perturbações externas. O controlo de FEL diminui o erro de posição em 15%, eliminando o desvio de fase, quando comparado com o controlador PID. Portanto, prova ser um controlo temporalmente eficaz e vantajoso para DAA. Trabalho futuro passa pela validação com mais sujeitos e diferentes estratégias de assistência.