Search

Altres ajuts: acords transformatius de la UAB The industrial sector is nowadays experiencing a digital transformation motivated by the Industry 4.0 paradigm. Concepts such as data-driven models, Artificial Neural Networks (ANNs), and Transfer Learning (TL) are part of the current vocabulary in the industrial management and control topics. For that reason, in this paper the application of TL techniques is proposed to derive new ANN-based control structures from pre-existing ones. Notice that if an ANN-based controller is transferred into a new industrial environment, its appropriate behaviour must be ensured, and what it is more important, this must be known a priori. Nevertheless, TL techniques do not always ensure this. That is why the Transfer Suitability Metric (TSM) is proposed here. Determining the similarity among environments, this metric tells if the controller can be transferred, transferred with certain limitations, or if it cannot be transferred at all. Here, the metric is applied over a Wastewater Treatment Plant (WWTP). The objective is to derive the control structure of one control loop, let us say the Dissolved Oxygen (DO), and then transfer it into another basic control loop in a WWTP, the Nitrate-nitrogen (NO), and vice-versa. Results show that with the help of the TSM, an improvement around a 68.54% and 80.53% in the Integrated Absolute Error (IAE) and the Integrated Squared Error (ISE) is obtained in the NO management, respectively. Moreover, a simplification and speed-up of the controller design process is achieved.

The article considers the problem of finding the optimal on average control of the trajectories of continuous stochastic systems with incomplete feedback. This class of problems includes control problems in which the initial states are described by a given distribution law; random effects on the control object are taken into account; and it is also assumed that information is available only about some coordinates of the state vector. As special cases, the problems of determining the optimal open-loop control and control with complete feedback in the presence of information about all state vector coordinates are considered. A method for parameterization of the control law based on expansions in various systems of basis functions is described. The problem of parametric optimization obtained is solved using a new metaheuristic multi-agent algorithm based on the use of extended PID (Proportional-Integral-Derivative) controllers to control the movement of agents. Solutions of three model examples of control of nonlinear continuous stochastic systems with interval constraints on the amount of control for all possible cases of state vector awareness are presented.

Reliable water resources management requires decision support tools to successfully forecast hydraulic data (stage and flow hydrographs). Even though data-driven methods are nowadays trendy to apply, they still fail to provide reliable forecasts during extreme periods due to a lack of training data. Therefore, model-driven forecasting is still needed. However, the model-driven forecasting approach is affected by numerous uncertainties in initial and boundary conditions. To improve the real-time model's operation, it can be regularly updated using measured data in the data assimilation (DA) procedure. Widely used DA techniques are computationally expensive, which reduce their real-time applications. Previous research shows that tailor-made, time-efficient DA methods based on the control theory could be used instead. This paper presents further insights into the control theory-based DA for 1D hydraulic models. This method uses Proportional–Integrative–Derivative (PID) controllers to assimilate computed water levels and observed data. This paper describes the two-stage PID controllers’ tuning procedure. Multi-objective optimization by Nondominated Sorting Genetic Algorithm II (NSGA-II) was used to determine optimal parameters for PID controllers. The proposed tuning procedure is tested on a hydraulic model used as a decision support tool for the transboundary Iron Gate 1 hydropower system on the Danube River, showing that the average discrepancy between modeled and observed water levels can be less than 0.05 m for more than 97% of assimilation window.

Accurate process modeling is occasionally difficult. In such situations, auto-tuning methods enable the design of suitable controllers based on experimental data and predefined mathematical approaches. Fractional order PIDs have recently emerged as a generalization of the standard PID controller, but auto-tuning methods for these controllers are scarce. In this paper, three sine-test based methodologies are presented from a control engineer's perspective consisting of novel Sine-Test, FO-KC and FO-ZN methods, with clear design and implementation guidelines. The approaches are exemplified on a highly nonlinear experimental platform. An in depth comparison is performed based on experimental closed loop system performance for wide operating areas, tuning effort and complexity, with a focus on the suitability for industrial applications. The study aims at providing a solid foundation for practitioners that desire to explore auto-tuning possibilities, presenting tuning workflows and implementation guidelines, while also considering the challenges associated with real-life process.

Aquest treball de fi de grau ha consistit en l’estudi dels algorismes de control Proporcional i Proporcional-Integral els qual s’han dissenyat per assolir certes especificacions sense la interacció humana. Les especificacions han consistit en mantenir el cotxe de slot circulant per el circuit a una velocitat constant de 100 cm/s utilitzant la visió Artificial i un algorisme de control en llaç tancat. El treball ha estat la continuació del TFG de l’alumna Roger Viaplana anomenat “Disseny i implementació d’un sistema de monitoratge i comandament d’un circuit slot” realitzat al 2017 on es dissenyava una aplicació amb la finalitat de controlar el cotxe de slot en llaç obert utilitzant l’eina Matlab. Per tal de millorar aquest treball es va dissenyar un programa mes robust utilitzant el llenguatge de programació Python per utilitzar la visió artificial i poder fer l’algorisme de control en llaç tancat. El treball s’ha dut a terme en l’edifici TR11, a l’aula 1.06 del primer pis, on es disposava d’una taula preparada amb el circuit de slot. També s’ha disposat de tot el material que va utilitzar en Roger, des de la càmera per realitzar la visió artificial com l’Arduino per poder enviar les senyals al circuit. Per tal de dissenyar l’algorisme de control s’ha dissenyat un programa per mesurar la velocitat del cotxe en tots el trams del circuit i després es va provar amb diferents valors de KP i KI fins trobar uns valors que complissin amb les especificacions establertes

In this master's project, the design for the additive manufacturing of a joystick has been created to later be able to materialize it through multi-material 3D printing so as to obtain a sustainable and simple model to print. The printing technique that has been used is called Fused Deposition Modelling (FDM). The model contains integrated sensors to allow linear and circular displacement. Two different materials have been combined, one conductive for the manufacture of the sensors and another structural for the manufacture of the rest of components. In the sensory part, resistive sensors have been designed to identify linear motion so that when the joystick is moved in one direction, the sensors perceive a traction or compression tension to give an electronic response. For circular motion, capacitive sensors have been designed so that one electrode is integrated into the lever and the other electrode into the joystick body. Theoretically, when a torque is applied to the lever, these electrodes form a capacitor that varies according the applied torque. In the initial phase of the project, bibliographical research has been carried out and the necessary printing parameters have been identified. After this, the design phase has been carried out, where different models have been created analysing all the components and their functionalities in order to obtain an effective and simple model. Some initial tests have been done with PLA to analyse the finish and quality before proceeding to the final printing. Three different geometry and component designs have been created. Design 3 has been the definitive one to be printed. The materials to be used for the printing were structural TPU and conductive TPU. Once printed, the sensory part has been configured. It has focused on circular motion using capacitive sensors since resistive sensors were developed in previous projects, so the linear motion was not included in the project scope. Four possible methods have been identified for measuring capacitance. Three methods based on the RC circuit and the last one based on the LC circuit. The first RC method identified distinct values but only in high value ranges. The second method using a 555 timer has failed due to unidentified internal electronic errors. However, the third RC method, which uses a 741 comparator, works correctly from 100 picofarads measures an above. The last method, based on LC circuit, has also been effective with similar range to the 741 method. It has been tried to test the joystick and no measurements could be detected. For this reason, it has returned to the design phase to rectify the last design and reduce the probability of failing in the measurement, although due to lack of time it was not possible to print the last design or analyse the results. Finally, the economic analysis and the environmental impact produced by the manufacture of the model have been carried out

This paper presents a hybrid metaheuristic method for optimal tuning of four different types of proportional-integral-derivative (PID) controller for an automatic voltage regulator (AVR) system. The method is based on the manta ray foraging optimization algorithm which is merged with the simulated annealing algorithm. Additionally, novel objective functions for the optimization of the controller’s parameters are proposed. The performance of the obtained ideal PID, real PID, fractional-order PID, and PID with second-order derivative controllers is verified by carrying out a comparison with the controllers tuned by different algorithms presented in the literature. Results of the simulations validate that each type of controller tuned with the proposed SA–MRFO algorithm outperforms the controllers tuned by other algorithms. Further, a comparative analysis is carried out to determine the most suitable controller for application in AVR systems. The main advantage of the proposed algorithm is the significant increase in the convergence speed.

Trabajo fin de máster presentado en la Universidad Politécnica de Cataluña, Máster Universitario en Ingeniería Industrial, El present treball planteja l’estudi i anàlisi previ per a poder desenvolupar una aplicació per al monitoratge dels controladors de posició dels eixos que disposen la gran majoria dels sistemes de paletitzat de l’empresa d’ensacat i paletitzat “Técnicas Mecánicas Ilerdenses”. L’objectiu principal d’aquest estudi és marcar les línies mestres per a poder desenvolupar l’aplicació en un futur i que aquesta permeti extreure dades rellevants durant el funcionament dels controladors per tal de maximitzar el rendiment dels sistemes de paletitzat, a més, de poder dotar als programadors de l’empresa d’ una eina d’utilitat a l’hora de poder configurar aquests dispositius electrònics. En aquest treball s’exposa el hardware necessari per dur a terme aquesta aplicació, quins paràmetres es voldran monitorar, com configurar els diferents elements que formen el sistema de paletitzat i una possible interfície gràfica on poder visualitzar tota la informació descrita en el treball.

The bachelor thesis deals with the design and practical implementation of the control of electric boilers through the TECOMAT system. The theoretical part describes the currently available solutions for the control of electric boilers and explains the reasons for the use of automated systems for this control. On the basis of the determined parameters, the TECOMA CP-1006 was selected by a subsequent analysis of suitable and currently available automated devices on the market, which meets all the necessary requirements. The paper deals with the control of heat sources and describes the different types of PID controllers. First of all, it deals with the actual design of the technical solution and control system for autonomous regulation of a specific electric boiler, production of the switchboard, creation of the software and its application to the selected automat. All this is complemented by the final setup and testing of the functionality of the entire system in practice.

In the literature, all investigations dealing with regulator design in the AVR loop observe the AVR system as a single input single output (SISO) system, where the input is the generator reference voltage, while the output is the generator voltage. Besides, the regulator parameters are determined by analyzing the terminal generator voltage response for a step change from zero to the rated value of the generator voltage reference. Unlike literature approaches, in this study, tuning of the AVR controllers is conducted while modeling the AVR system as a double input single output (DISO) system, where the inputs are the setpoint of the generator voltage and the step disturbance on the excitation voltage, while the output is the generator voltage. The transfer functions of the generator voltage dependence on the generator voltage reference value and the excitation voltage change were derived in the developed DISO-AVR model. A novel objective function for estimating DISO-AVR regulator parameters is proposed. Also, a novel metaheuristic algorithm named hybrid simulated annealing and gorilla troops optimization is employed to solve the optimization problem. Many literature approaches are compared using different regulator structures and practical limitations. Furthermore, the experimental results of 120 MVA synchronous generators in HPP Piva (Montenegro) are presented to show the drawbacks of the literature approaches that observe generator setpoint voltage change from zero to the rated value. Based on the presented results, the proposed procedure is efficient and strongly applicable in practice.

Orientador: Jose Geraldo Pena de Andrade Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo Resumo: Este trabalho apresenta uma nova proposta para obter os parâmetros do regulador de uma turbina hidráulica, com o objetivo de melhorar o controle operacional de uma usina hidrelétrica. Dentre os diversos métodos existentes, o método de Ziegler-Nichols mostra-se adequado porque na determinação dos parâmetros do regulador efetuam-se simulações que consideram todo o comportamento hidráulico da instalação e da máquina. A partir de inúmeras simulações, para a estabilização da rotação adimensional, variando o tempo da água, o tempo da máquina e a rejeição, percebeu-se que os coeficientes utilizados no método de Ziegler-Nichols não apresentavam bons resultados em algumas situações, deixando evidente a necessidade de uma adequação. As equações propostas neste trabalho permitem a obtenção de valores mais adequados para as constantes proporcional, integral e derivativa através dos valores da constante proporcional última e do período último, como já utilizado no método de Ziegler-Nichols, em função do tempo da água, do tempo da máquina e da rejeição da potência Abstract: This work presents a new proposal to obtain the parameters of the regulator of a hydraulic turbine, looking for the goal to increase the operational control of a hydroelectric power plant. Among many existing methods, the Ziegler-Nichols shows itself adequate because in the determination of the parameters of the regulator simulations are carried out witch consider all the hydraulic behavior of the installation and the machine. From many simulations, to the adimensional rotation stabilization, varying the water time, the machine time and the rejection, it was realized that the coefficients used in the Ziegler-Nichols method weren't presenting good results in some situations, leaving evident the needy of an adaptation. The equations suggested in this work allow obtaining more adequate values to the proportional, integral and derivative constants, through the constant last proportional values and the last period, as already used in the Ziegler-Nichols method in function of the water time, the machine time and the power rejection Doutorado Recursos Hídricos Doutor em Engenharia Civil

Orientadores: Denis José Schiozer, Eduardo Gildin Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica Resumo: A simulação acoplando reservatórios e sistemas de produção é um problema desafiador e pode se tornar uma tarefa difícil caso modelos intensivos computacionalmente com múltiplos reservatórios e sistemas de produção complexos sejam considerados. Todavia, simulações aplicando a técnica de acoplamento podem promover melhor precisão na previsão de produção, especialmente em planos de desenvolvimento de longo prazo. A integração dos sistemas petrolíferos pode ser realizada por duas metodologias principais: utilizando diferentes simuladores (acoplamento explícito) ou considerando todos componentes individuais do sistema em um único programa (acoplamento implícito). O método explícito é mais flexível, permitindo a integração entre simuladores comerciais preparados para cada aplicação. Como desvantagem, soluções oscilatórias podem ser geradas. Neste trabalho, uma nova metodologia para redução das instabilidades numéricas (oscilações) decorrentes do acoplamento explícito é formulada por meio de uma configuração de controle. Resultados deste trabalho mostram que o acoplamento explícito sem um mecanismo para evitar instabilidades numéricas apresenta oscilações que podem crescer ao longo da simulação. A razão desse efeito é atribuída a curva IPR (Inflow Performance Relationship) e consequentemente a vazão do ponto de operação (q_OP) permutados no início do passo de tempo entre simulador de reservatórios e programa acoplador, os quais podem não ser representativos para todo intervalo de acoplamento. A fim de reduzir as oscilações numéricas, é implementado um tipo de sistema de controle por feedback, conhecido como controlador PID (Proporcional, Integral e Derivativo). O controlador PID, com parâmetros (K_C,?_I,?_D) sintonizados manualmente para um grupo de configurações de poços, ajusta a curva IPR tradicional gerada pelo simulador de reservatórios, de forma que o erro entre a pressão de fundo de poço calculada pelo simulador de reservatórios (?BHP?_RS) e a pressão de fundo de poço definida pelo ponto de operação (?BHP?_OP) seja mínimo. Dessa forma, é obtido um valor de q_OP representativo para o intervalo de acoplamento. A nova metodologia foi testada em um modelo numérico sintético (UNISIM-I-D) baseado no campo de Namorado (Bacia de Campos ¿ Brasil), composto por 20 poços satélites (7 injetores e 13 produtores). O controle PID reduz oscilações nas variáveis vazão e pressão no estudo de caso e, além disso, os resultados convergem com o caso base que representa o sistema de produção dos poços produtores por meio de tabelas apropriadas de perda de carga. Palavras Chave: Acoplamento Explícito; Curva IPR; Oscilação; Controlador PID Abstract: Simulation coupling subsurface (reservoir) and surface (network) systems is a challenging problem and can become a daunting task if computationally intensive multi-reservoir models and complex surface network facilities are considered. Nevertheless, simulations applying the coupling technique can bring greater accuracy in production forecast, especially in long-term field development plans. Integration of petroleum systems can be done by two principal methodologies: using different simulators (explicit coupling) or considering all individual components of the system in one simulator (implicit coupling). The explicit method is more flexible, allowing the integration of commercial-off-the-shelf simulators. However, as a drawback, it can yield oscillatory solutions. In this work, a new framework for mitigating explicit coupling numerical instabilities (oscillations) is developed by recasting the problem in a control setting. Results from this work show that explicit coupling without a mechanism to avoid numerical instabilities presents oscillations that can grow throughout the simulation. The reason for such effect is attributed to the IPR (Inflow Performance Relationship) curve and consequently the operating point flow rate (q_OP) exchanged at the beginning of each time step between the reservoir simulator and the coupling program, which may not be representative for the entire coupling interval. In order to mitigate the numerical oscillations, one type of feedback control system, namely a PID (Proportional, Integral and Derivative) controller is applied. The PID controller, with parameters (K_C,?_I,?_D) tuned manually for a group of well settings, adjusts the traditional IPR curve generated by the reservoir simulator so that the error between the bottom-hole pressure calculated by the reservoir simulator (?BHP?_RS) and the bottom-hole pressure defined in the operating point (?BHP?_OP) is minimal. In this case, a q_OP value representative for the entire coupling interval is obtained. The new methodology was tested in a synthetic numerical model (UNISIM-I-D) based on Namorado field (Campos Basin ¿ Brazil), comprised by 20 satellite wells (7 injectors and 13 producers). The PID control reduces the rate and pressure oscillations in the case study, and results converge with base case scenario, which represents the network system of producer wells by proper pressure drop tables. Key Word: Explicit Coupling; IPR Curve; Oscillation; PID Controller Mestrado Reservatórios e Gestão Mestre em Ciências e Engenharia de Petróleo CAPES 33003017

Orientador: Vivaldo Silveira Junior Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos Mestrado Mestre em Engenharia de Alimentos

With the “New Space” era we are now seeing a prominent rise in the development of Reusable Launch Vehicles with vertical landing capabilities. This project aims to design and construct a scaled model of such a vehicle but using a cold gas thruster as a means of propulsion. In order to do so, multiple disciplines of engineering are required to develop critical systems such as retro-propulsion, thrust vector control and aerobraking. From structural simulations and CFD analysis to stabilization algorithms and FDM manufacturing, all the methods employed to carry out this complex task presented their complications and challenges, all of which had to be recorded, analysed and overcome. The propellant chosen for the task of propulsion was compressed air, due to its compatibility and availability. Design requirements were established from the beginning but as the project evolved it was clear several of these could not be realized due to limitations of the components available. Most noticeably, the maximum thrust value was found to be restricted by the propulsion system, which makes it impossible to achieve sufficient deceleration for a controlled landing. Having said that, the project successfully lays down the foundations for future iterations and outlines the next steps required in order to solve the main issues related to thrust. If these issues were to be resolved, there is confidence in coming closer to the project’s aim of using compressed air as a means of propulsion

The paper presents an automated system for the temperature control using a PIC microcontroller, a digital temperature sensor with I2C and a MOSFET as actuator. The control strategy is a proportional-integrative one, preceded by an on-off algorithm. The most important data is presented on a graphical interface. In order to send the parameters of the process and the command states to the computer, the serial communication is used.

Orientador: José Antenor Pomilio Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de Computação Resumo: Este trabalho aborda as características que envolvem o gerenciamento da operação de um sistema monofásico de geração distribuída. Embora tais características possam ser expandidas para sistemas trifásicos e de potência elevada, o sistema proposto está relacionado com aplicações de geração distribuída em baixa tensão ou naquelas que envolvam consumidores residenciais. O funcionamento do sistema proposto é baseado em um conversor eletrônico de potência elaborado a partir da estrutura multinível na topologia cascata assimétrica de 19 níveis. Nesta topologia, as tensões dos barramentos CC devem ser isoladas e desiguais entre si. Tal condição permite o envolvimento, nos barramentos CC do inversor, de múltiplas ou diferentes fontes alternativas de energia elétrica tais como sistemas fotovoltaicos, sistemas de células a combustível ou sistemas eólicos associados com conversores CC/CC. Com o sistema em operação, busca-se uma injeção apenas de potência ativa no sistema de distribuição alimentador e um fornecimento ininterrupto de energia elétrica para uma carga local mesmo quando nesta predominar características não-lineares de alimentação. Assim, de acordo com os seus objetivos, o sistema proposto opera de forma contínua e intercalada entre os modos ilhado e compartilhado. Detalhes sobre tais modos de operação e suas respectivas transições são apresentadas. As transições envolvem a detecção de ilhamento e o êxito no sincronismo. Em função disso, é apresentado um método ativo de detecção de condições de ilhamento. Tal método representa a adaptação de um método ativo já existente (AFDPF) aos requisitos de operação do sistema proposto neste trabalho. Justificativas e detalhes dessa adaptação do método ativo AFDPF são apresentados. Com relação à outra transição, um método de sincronismo baseado em técnicas PLL é apresentado. Tal método de sincronismo atende os requisitos estabelecidos em IEEE Std 1547-2003, diminuindo os impactos de uma possível religação com o sistema de distribuição. Para permitir um melhor funcionamento sob diferentes requisitos, também são descritas as etapas que envolvem os métodos de projeto dos controladores adotados: controlador PI de corrente de saída; controlador PI de potência média injetada; e controlador P+Ress de tensão na carga. Em especial, é apresentada uma nova metodologia de projeto do controlador proporcional e ressonante (P+Ress) de tensão baseada na sua resposta em malha fechada observada no domínio do tempo, em contrapartida ao seu método clássico de projeto baseado no domínio da freqüência. Um modelo matemático para simulações computacionais e um protótipo experimental utilizando o DSP TMS320F2812 foram considerados. Resultados de simulações computacionais e experimentais são comparados e permitem a verificação do comportamento do sistema proposto sob condições normais e anormais de operação Abstract: This work regards the issues related to the operation management of a single-phase distributed generation system. Although these issues can be applied three-phase systems and high power systems, the proposed system is related to low voltage distributed generation applications or related to residential consumers. The operation of the single-phase proposed system is based on an utility-interactive power electronics converter which is composed by an asymmetrical cascaded multilevel inverter. This topology is able to create an output signal with up to 19 levels and it is supplied by DC voltage power sources that must be isolated and unequal from each other. By this demand it is possible to combine multiple and/or different alternative DC voltage power supplies as photovoltaic, fuel cells or wind energy systems into the DC buses of the single-phase multilevel inverter. During the operation of the proposed system, an injection of only active power into the grid utility and an uninterrupted load supply are achieved even when the local load (or group of local loads) has predominant nonlinear characteristics. For those reasons the proposed system operates continuously and alternately between two operation modes: grid-connected mode and stand-alone mode. Details about them and its transitions are also presented. The transitions are related to a correct detection of islanding situations and also to an effective synchronization method. The islanding detection is achieved by adaptations on an already known active method (AFDPF) to accomplish the project's goals. The reasons and details about these adaptations are presented. Furthermore the synchronization method is described and it is based on PLL techniques. Both transition methods meet the IEEE Std 1547-2003 requirements and it decreases the impacts from the proposed system into grid utility. To guarantee a suitable operating under several conditions, a wide range of operation points can be found by using the design methods described to each proposed controller: PI output current controller; PI injected active power controller; and a P+Ress load voltage controller. In highlights it is proposed a new design method to proportional and resonant controller (P+Ress) based on its closed-loop time response, instead of the classical method based on its open-loop frequency response. A mathematical model for simulations and an experimental low power prototype based on DSP TMS320F2812 have been considered. Simulation and experimental results are compared and they allow examining the performance of the proposed system operating under normal and abnormal conditions Doutorado Energia Elétrica Doutor em Engenharia Elétrica

Orientador: Paulo Sérgio Graziano Magalhães Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agrícola Resumo: O objetivo principal desse trabalho consistiu em desenvolver um dispositivo de controle que permitisse aplicação em taxa variável e em tempo real de fitorreguladores na cultura do algodoeiro. Assume-se a hipótese que "utilizando um dispositivo de controle com sistema hidráulico e controle eletrônico, é possível, em tempo real, variar a taxa de aplicação de fitorreguladores no algodão, baseado nas informações obtidas nos sensores de ultrassom, que detectam a altura das plantas também em tempo real; no algoritmo de crescimento da planta e na dosagem do fitorregulador estabelecido pelo usuário do sistema". O dispositivo proposto é composto de três sistemas: Hidráulico, Ultrassom e Controle. O sistema Hidráulico consiste do comando de pulverização e circuito eletrônico para aquisição de dados e atuação nos componentes desse comando. O sistema de Ultrassom é um circuito eletrônico composto por um conjunto de sensores ultrassom que realizam a medição da altura de plantas de algodão. O sistema de Controle é o núcleo do dispositivo, pois é o responsável por gerenciar as informações dos sistemas Hidráulico e de Ultrassom e, com um algoritmo de controle Proporcional-Integral-Derivativo (PID) retroalimentado pelo sensor de pressão e regras de aplicação de fitorregulador, é capaz de variar a dose em tempo real controlando as válvulas do comando de pulverização. Os circuitos eletrônicos foram desenvolvidos com base na arquitetura microcontrolada PIC18F452 e comunicação sem fio por meio de módulos de rádio frequência que implementam o protocolo ZigBee. Para o desenvolvimento das interfaces de validação dos três sistemas adotou-se tecnologias de software livre como a linguagem de programação Java, ambiente de desenvolvimento Netbeans e sistema operacional Linux. Para validação do Dispositivo proposto, foi utilizado um mapa de uma área de 7.3 ha com o registro georeferenciado de alturas de plantas de algodão e regras de aplicação de fitorregulador, considerando as velocidades de pulverização 2,5 m.s-1 e 5 m.s-1. Independentemente das velocidades simuladas, houve potencial economia de aplicação de regulador de crescimento Também foram realizadas validações para verificar se o dispositivo proposto manteria a pressão desejada simulando o entupimento de bico de forma lenta e rápida. Os resultados mostram que em ambas as situações a pressão é mantida próxima do valor desejado. Com os resultados obtidos, conclui-se que o dispositivo proposto atende ao objetivo de sua proposição Abstract: The main objective of this project was to develop a prototype device control capable to accomplish the application of plant growth regulator at variable rate in real time in cotton crop. We assume the hypothesis that "by using a control device with hydraulic and electronic control, it's possible to vary the application of plant growth regulator in cotton crop, based on the information obtained from the ultrasound tranducers to detect the height of the plants in real time; the plant growth algorithm and plant growth regulator dosage established by the system user". In the devise proposed there are three systems: Hydraulic, Ultrasound and Control. The Hydraulic system is compound by the sprayer command and electronic circuit for data acquisition and actuation in the components used in the sprayer command. The Ultrasound system is a electronic circuit composed by a set of ultrasound sensors that measure the cotton plants height. The Control system is the core of the Device, because it's responsible by the information management in the hydraulic and ultrasound systems and, with a control algorithm Proportional-Integral-Derivative (PID) retrofitted by the pressure sensor and application rules of plant growth regulator, it?s capable of varying the dose in real time by controlling the valves of the spray command. The electronic circuits were developed based on the PIC18F452 microcontrolled architecture and wireless communication by radio frequency modules that implement the ZigBee protocol. In the development of the three systems validation interfaces we have adopted the technology of the open source tools as Java, IDE Netbeans and Linux operational system. To validate the device, we have used 7,3 ha of heights cotton plants previously mapped and rules application of plant growth regulator, considering the sprayers velocity 2,5 m.s-1 e 5 m.s-1. Regardless the speed simulates, there were a potential economy of regulator growth application. Validations were also performed to verify if the device could keep the desired pressure. We have simulated the nozzle obstruction in a fast way and in a slow way. The results show that both situations the pressure is kept near the desired value. With these results the device reach the objective of this proposition Doutorado Máquinas Agrícolas Doutor em Engenharia Agrícola

Orientadores: Katia Lucchesi Cavalca Dedini, Ricardo Ugliara Mendes Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica Resumo: Atuadores eletromagnéticos são amplamente utilizados em aplicações industriais que vão desde excitadores (apropriados quando excitação sem contato é requerida ou desejada) a aplicações mais complexas como controle de vibração em mecanismos (como braços robóticos). No presente estudo, um atuador eletromagnético é utilizado juntamente com um controlador PID para suprimir a vibração de uma viga metálica em balanço, em três condições complementares: frequências naturais da viga; regime transiente; e excitação aleatória. Para garantir a correta sintonia do controlador PID e consequentemente a eficiência do atuador, os dois principais parâmetros da viga (i.e., o módulo de Young do material e os adequados coeficientes do amortecimento estrutural proporcional) foram identificados, de modo que o modelo em elementos finitos estivesse o mais próximo possível do comportamento dinâmico real da viga em balanço. O ajuste do modelo foi obtido por comparação de funções de resposta em frequência (FRF), experimentalmente obtidas, às respostas do modelo, oriundas de simulações numéricas. Então, o teste de realimentação por relê foi empregado tanto ao modelo quanto ao sistema físico para se determinar o ganho crítico e o período crítico dos sistemas em malha fechada. A partir destes parâmetros, cinco diferentes controladores PID foram sintonizados e empregados na bancada de testes, podendo-se avaliar comparativamente suas eficiências tanto em reduzir a amplitude de vibração do sistema controlado, como também em conduzir este sistema a sua posição de referência. Os ajustes, sintonias e ensaios foram repetidos considerando-se duas diferentes formas de excitar o sistema: com um dispositivo excitador eletromecânico (shaker) e com um martelo de impacto Abstract: Electromagnetic actuators are widely used in industrial applications, ranging from exciters (very appropriate when excitation with no contact is required or desired) to more complex applications such as vibration control in mechanisms (such as robotic arms). In the present study, an electromagnetic actuator is used in combination with a PID controller to suppress the vibration of a flexible cantilever metallic beam, in three complementary conditions: natural frequencies of the beam; transient regime; and random excitations. To guarantee the correct tune of the PID controller and consequently the efficiency of the actuator, the two main parameters of the beam (i.e. the Young¿s modulus of the material and the adequate coefficients for proportional structural damping) were experimentally identified, so that the finite element model was as close as possible to the real dynamic behavior of the cantilever beam. The model adjustment was performed by comparing the frequency response functions (FRF) experimentally obtained and the model responses, obtained by numerical simulation. So, the relay feedback test was used both to the model and the physical system to determine the ultimate gain and the ultimate frequency of the closed loop systems. From these parameters, five different PID controllers were tuned and used in the test rig, being possible to compare their efficiencies both in reducing the vibration amplitude of the controlled system, and in conducting the system to its reference position. The adjustments, the tunes and the tests were repeated considering two different forms of system excitation: an electromechanic exciter (shaker) and an impact hammer Mestrado Mecânica dos Sólidos e Projeto Mecânico Mestre em Engenharia Mecânica CAPES 33003017

Orientador: Nelson Luis Cappelli Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agricola Resumo: O armazenamento de produtos perecíveis em sistemas refrigerados permite conservar por mais tempo sua qualidade para consumo, atender a padrões mais rígidos de qualidade, prolongar a vida de prateleira, e muitas vezes alcançar mercados antes inalcançáveis, principalmente para exportação. Além dos fatores de conservação, a redução de custos nos insumos permite a concorrência por menores preços. Na refrigeração, um importante insumo é a energia elétrica, reduzir seu custo significa mais competitividade. Portanto, neste trabalho, estuda-se a possibilidade de reduzir o consumo de energia elétrica num sistema de refrigeração, originalmente concebido para regime de rotação fixa do compressor, quando submetido a um regime de rotação variável. Para tal investigação, utilizam-se simulações de modelos matemáticos. Fez-se necessário identificar cada parte do sistema dinâmico; construir o modelo matemático; estudar as estratégias de controle mais adequadas, tanto em função do consumo de energia, quanto em relação a estabilidade das variáveis controladas em regime permanente; discutir os aspectos relevantes para a implementação dos sistemas de controle e classificar as estratégias de controle quanto ao consumo de energia e viabilidade de implementação. O sistema de refrigeração foi identificado e concebido num modelo matemático de múltiplas entradas e múltiplas saídas. Nas simulações foram implementados controle de temperatura liga-desliga, controlador PID e controle fuzzy. Buscou-se com os controles maior estabilidade de temperatura, o menor erro em regime permanente e o menor consumo de energia elétrica. Quanto a estabilidade de temperatura e erro em regime, tanto o PID quanto o fuzzy obtiveram desempenho satisfatório, com respectivamente Imse=0,0019 e Imse=0,46485, comparados ao liga-desliga com Imse=0,5813. Apenas o controle fuzzy obteve economia no consumo de energia elétrica, chegando a redução de 5,4% quando comparado aos demais Abstract: The storage of perishable products in refrigerated systems lets people maintain even more the quality for consume, fulfill the most inflexible patterns of quality, lengthen the shelf life, and many times reach markets that were unreachable, mainly for exportation. Besides quality, there is a competition for lower prices, and it is esteemed then, among others, the reducing in costs of the raw materials. Talking about refrigeration, an important raw material is electric energy, so reduce its cost means to be more competitive. So, in this work, it is experimented the possibility of reducing the consumption of electric energy in a refrigeration system originally conceived for method of fixed rotation of the compressor when submitted to the system of changeable rotation. To this searching, in this work simulations of mathematical models are used. So it was necessary to identify each part of the dynamic system; to build a mathematical model; to study the more appropriate strategies of controlling, as much related to the consumption of energy, as in relation to the stability of the variables controlled when they are under steady state; to discuss the significant aspects to the execution of the control systems and to classify the control strategies according to the consumption of energy and the viability of execution. The refrigeration system was identified and conceived in a mathematical model of multiple inputs and outputs. In the simulations, control of temperature with on-off , PID and fuzzy control were executed. It sought through the controls a higher stability in temperature, the smaller error in steady state and the lower consumption of electric energy. As for stability in temperature, as much the PID as the fuzzy had a satisfactory performance, with respectively IMSE=0,0019 and IMSE=0,46485 compared to the on-off with IMSE=0,5813; as for the error in steady state the control PID got better results; as for the decreasing in the consumption of electric energy, only the fuzzy control has got economy, reaching reductions of 5,4%, in comparison with the other ones Mestrado Máquinas Agrícolas Mestre em Engenharia Agrícola

In the last decade, twisted coiled actuators (TCAs) made from nylon have drawn the attention of the community as an attractive electroactive mechanism mimicking the performance of human muscles, with notably favourable output power densities. The feasibility of the TCA, in terms of performance, size, safety, and scalability has been evaluated in previous studies, but they exhibit substantially non-linear behaviour, thereby requiring a sophisticated control system. Furthermore, it is desired that these actuators are able to rapidly actuate to match biological muscle levels of capability. To this end, the efficacy of a linear physics-based model of TCAs was tested to elucidate the relationship between temperature, force, and displacement in these actuators. The accuracy of this modelling approach is discussed in the context of position control theory using a two-degree- of-freedom proportional-integral-derivative (PID) controller to switch between Joule heating and active cooling with a continuously controlled fan to enhance actuator response time. This model was subsequently employed to simulate the TCA response to heating and cooling in the MATLAB-Simulink® environment while referencing the experimental results reported by Takagi et al. as a benchmark. Results from this investigation indicate a 5% offset error, which is attributed to the non-linear nature of the TCA. Finally, results confirm that TCAs augmented with active cooling exhibit significantly improved cycle times relative to conventionally heat-controlled TCAs.

O objetivo deste trabalho é criar um estudo comparativo de quais estratégias metaheurísticas bioinspiradas podem ser as melhores para otimizar os ganhos ótimos de um sistema de controle PID Adaptativo Gaussiano para um Conversor Buck. Isso vem de duas necessidades, a primeira é que para superar o desempenho dos sistemas de controle linear é necessária uma estratégia mais avançada como o controle adaptativo; a segunda é que como não existem métodos de otimização determinísticos para tais estratégias, o uso de metaheurísticas é considerado necessário, e de acordo com o teorema do No Free Lunch tais estudos comparativos devem ser feitos para entender quais técnicas de otimização são mais adequadas para tal problema. As técnicas escolhidas foram o Algoritmo Genético, a Otimização do Enxame de Partículas e a Evolução Diferencial. O Gaussian Adaptive PID (GAPID) foi escolhido para o controle adaptativo por ser ser baseado na função Gaussiana, que é uma curva suave com derivadas suaves que evita vibrações e mudanças bruscas no controle. Depois de avaliar as respostas encontradas na simulação de todas as variações de cada uma das estratégias de otimização, foi criada uma comparação analítica e estatística de cada técnica mostrando como um sistema de controle adaptativo pode gerar uma resposta mais rápida e robusta quando comparado ao PID linear. The objective of this work is to realize a comparative study of which bio-inspired metaheuristic strategies are the best to be used when finding the optimal gains for a Gaussian Adaptive PID control system applied to a Buck Converter. This comes from two necessities, the first one is that to surpass the performance of linear control systems a more advanced strategy such as adaptive control is required; the second is that since there are no deterministic optimization methods for such strategies, the use of metaheuristics is deemed necessary, and according to the No Free Lunch theorem such comparative studies ought to be made to understand what optimization techniques ares better suitable for such a problem. The chosen techniques were the Genetic Algorithm, the Particle Swarm Optimization and the Differential Evolution. The Gaussian function is employed as the adaptive rule because it is a smooth curve with smooth derivatives that avoids the potential of chattering and abrupt control changes. After evaluating the responses found from simulating all variations of each of the optimization strategies we were able to create an analytical and statistical comparison of each technique and show how an adaptive control system can create a faster and more robust response when compared to the linear PID.

The master thesis exposed on the present document illustrates the development of a Permanent Magnet Synchronous Motor (PMSM) model for Hardware-in-the-Loop (HiL) applications. The real-time simulations employed in HiL have proved to be an effective tool for Model-Based Designing (MBD) methodologies. The information relative to the functioning of PMSM, Variablefrequency drives and controllers for this kind of motors, as well as the required equations for the development of the model, are detailed in the first chapter of this report. Later, the software installation and the setup of hardware devices has been carried out as well. Afterwards, the most important concepts, related to real-time simulations, in computing science and numerical methods have been studied to manage the complexity of this kind of models. The modelling of the PMSM, inverter, controller, PWM generator and resolver is performed in conjunction with deep research on each field. Besides, an operating methodology, including MATLAB code scripts, has been developed for an efficiency improvement on testing execution for MBD implementations. Finally, the designing and execution of electronic connections between hardware devices have been made, and many tests performed for validating all the models created. Additionally, a comparison between tests with a real PMSM and the motor simulated with the model developed constitute the ultimate validation

Desde hace años, en el Departamento de Ingeniería de Sistemas, Automática e Información Industrial de la UPC en Vilanova y la Geltrú, se ha buscado que los alumnos aprendan a aplicar la teoría impartida en sus asignaturas. Por esta razón se ha propuesto este proyecto. El principal objetivo de este proyecto es la implementación de un controlador PID para, posteriormente, realizar una comparación de los diferentes sensores utilizados. Otro objetivo importante es el desarrollo del modelo, para obtener la función de transferencia que relaciona la respuesta del sistema con la señal de entrada. También se busca implementar una práctica de este sistema para los alumnos de las asignaturas de control de sistemas. Este sistema consta de un ventilador de 4 hilos que ejerce de actuador, siendo controlado por PWM. Como sistema de sensado, se utilizan 3 sensores distintos de distancia; un sensor ultrasonidos, un sensor infrarrojo y un sensor láser infrarrojo. El control del sistema se hace mediante una placa de Arduino Uno, en la cual se implementará un controlador PID. La planta del sistema está compuesta por un tubo de metacrilato y una bola de porexpan, la cual es el objeto levitado. Para determinar la consigna, se utiliza un sensor de ultrasonidos y un potenciómetro. Como sistema de visualizado, se utiliza una pantalla LCD y unos diodos LED que indican si la consigna ha sido alcanzada o no. Como resultado, se ha podido implementar correctamente un control PID. En cuanto a la comparación de los 3 sensores, se ha obtenido que, el sensor ultrasonidos y el láser infrarrojos tienen un control parecido. En cambio, el sensor infrarrojo, ha sido un fracaso, ya que le era imposible seguir la bola dentro del tubo. Se ha obtenido que el sensor de ultrasonidos es el más adecuado. Para la linealización del sistema, se hizo una hipótesis basada en que la altura y la velocidad del aire eran independientes. Mediante ésta, se obtiene que la función de transferencia tiene un integrador. Entonces, en lazo cerrado y ante una entrada unitaria, el sistema debe actuar con error nulo en estado estacionario. Como esto no ocurre, la velocidad del aire no es independiente de la altura. Finalmente, se propone como mejoras, la linealización partiendo de la premisa de tener un en cuenta que la velocidad del aire y la altura no son independientes. También se puede mejorar y rediseñar la estructura física del sistema para que ésta sea más económica. The UPC’s Department of Systems Engineering, Automation and Industrial Information in Vilanova y la Geltrú, always wanted to all their students learn to apply the theory taught in their subjects. For this reason, this project has been proposed. The main objective of this project is the implementation of a PID controller to, afterwards, make a comparison of the different sensors used. Another important objective is the development of the model, to obtain the transfer function that relates the response of the system to the input signal. It also seeks to implement a practice of this levitator to students of systems control subjects. This system consists of a 4-wire fan that acts as an actuator, being controlled by PWM. As a sensor system, 3 different distance sensors are used; an ultrasonic sensor, a laser infrared sensor and an infrared sensor. The control is an Arduino Uno board, in which a PID controller will be implemented. The plant of the system is composed of a methacrylate tube and a porexpan ball, which is the levitated object. To determine the reference, an ultrasonic sensor and a potentiometer are used. As a display system, an LCD screen and LEDs are used to indicate whether the reference has been reached or not. As a result, a PID control have been successfully implemented. In one hand, the comparison of the 3 sensors, has obtained that the ultrasound sensor and the infrared laser have a similar control. On the other hand, the infrared sensor has been a failure, because was not possible for it to follow the ball inside the tube. Moreover, the ultrasound sensor is the most suitable. For the linearization of the system, a hypothesis was made based on the fact, that the height and the air speed were independent. By means of this, it is obtained that the transfer function has an integrator. Then, in closed loop and facing a unit input, the system must act with zero error in steady state. As this does not happened, the air speed is not independent of the height. Finally, is proposed as improvements, starting the linearization from the premise of considering that air speed and height are not independent. Also, improve and redesign the physical structure of the system to make it more economical.

L’objectiu d’aquest projecte és la realització d’un laboratori de control de temperatura per a aplicacions docents. El projecte consisteix en el disseny d’una placa de circuit imprès (PCB) que, conjuntament amb un Arduino MEGA 2560 Rev3, conformin una planta de temperatura la qual permeti a l’usuari controlar la temperatura de cada transistor BJT. Per tal d’aconseguir controlar la temperatura d’aquests, es dissenyaran diferents algoritmes de control amb l’ajuda de programes numèrics com són Matlab i Arduino. La planta de temperatura està formada per la PCB, l’Arduino MEGA 2560 Rev3, dos transistors BJT, dos sensors TMP36, un LED, una pantalla OLED, un teclat de 4 files per 4 columnes i un ventilador. En la memòria del projecte s’expliquen la utilitat d’aquests components. Finalment, es realitzaran simulacions i anàlisis de la PCB i, comparacions entre diferents controladors. El proyecto consiste en la realización de un laboratorio de control de temperatura para aplicaciones docentes. El proyecto consiste en el diseño de una placa de circuito imprimido (PCB) que, conjuntamente con uno Arduino UNO Rev3, conformen una planta de temperatura la cual permita al usuario controlar la temperatura de cada transistor BJT. The aim of this project is to create a temperature control lab for teaching applications. The project consists of the design of a printed circuit board (PCB) that, together with an Arduino MEGA 2560 Rev3, conform a temperature plant that allows the user to control the temperature of each BJT transistor. In order to control the temperature of these, different control algorithms will be designed with the help of numerical programs such as Matlab and Arduino. The temperature plant is composed of the PCB, the Arduino MEGA 2560 Rev3, two BJT transistors, two TMP36 sensors, one LED, an OLED display, a 4x4 keypad and a fan. In the project, the utility of this components is explained. Eventually, simulations and analysis of the PCB will be performed and comparisons between different controllers will be made.

Real control systems require robust control performance to deal with unpredictable and altering operating conditions of real-world systems. Improvement of disturbance rejection control performance should be considered as one of the essential control objectives in practical control system design tasks. This study presents a multi-loop Model Reference Adaptive Control (MRAC) scheme that leverages a nonlinear autoregressive neural network with external inputs (NARX) model in as the reference model. Authors observed that the performance of multi-loop MRAC-fractional-order proportional integral derivative (FOPID) control with MIT rule largely depends on the capability of the reference model to represent leading closed-loop dynamics of the experimental ML system. As such, the NARX model is used to represent disturbance-free dynamical behavior of PID control loop. It is remarkable that the obtained reference model is independent of the tuning of other control loops in the control system. The multi-loop MRAC-FOPID control structure detects impacts of disturbance incidents on control performance of the closed-loop FOPID control system and adapts the response of the FOPID control system to reduce the negative effects of the additive input disturbance. This multi-loop control structure deploys two specialized control loops: an inner loop, which is the closed-loop FOPID control system for stability and set-point control, and an outer loop, which involves a NARX reference model and an MIT rule to increase the adaptation ability of the system. Thus, the two-loop MRAC structure allows improvement of disturbance rejection performance without deteriorating precise set-point control and stability characteristics of the FOPID control loop. This is an important benefit of this control structure. To demonstrate disturbance rejection performance improvements of the proposed multi-loop MRAC-FOPID control with NARX model, an experimental study is conducted for disturbance rejection control of magnetic levitation test setup in the laboratory. Simulation and experimental results indicate an improvement of disturbance rejection performance.

Nowadays the industrial field is testing more robust controllers to deal better with complex control processes, to guarantee high reliability and efficiency. In this context, this work aims to present the design of a Fuzzy Controller embedded in an Arduino Mega microcontroller, taking 2 experimental didactic plants into consideration: a resistor-capacitor circuit and a direct current motor assembly. Then, the Fuzzy Controller will have its effectiveness and also be compared with other topology: the parallel PID controller. In addition, an interesting study is done when the storage capacity of routines in the Arduino board is considered, regarding the dynamic memory when new membership functions and rules are increased. The Fuzzy controller was embedded obtaining satisfactory results when compared to the PID controller, taking non-intrusive performance indices as validation parameters.

Due to unpredictable and fluctuating conditions in real-world control system applications, disturbance rejection is a substantial factor in robust control performance. The inherent disturbance rejection capacity of classical closed loop control systems is limited, and an increase in disturbance rejection performance of single-loop control systems affects the set-point control performance. Multi-loop control structures, which involve model reference control loops, can enhance the inherent disturbance rejection capacity of classical control loops without degrading set-point control performance, while the classical closed Proportional Integral Derivative (PID) control loop deals with stability and set-point control, the additional model reference control loop performs disturbance rejection control. This adaptive disturbance rejection, which does not influence set-point control performance, is achieved by selecting reference models as transfer functions of real control systems. This study investigates six types of multi-loop model reference (ML-MR) control structures for PID control loops and presents straightforward design schemes to enhance the disturbance rejection control performance of existing PID control loops. For this purpose, linear and non-linear ML-MR control structures are introduced, and their control performance improvements and certain inherent drawbacks of these structures are discussed. Design examples demonstrate the benefits of the ML-MR control structures for disturbance rejection performance improvement of PID control loops without severely deteriorating their set-point performance.

En este proyecto se obtiene el modelo matemático del sistema no lineal formado por un péndulo invertido sobre una base móvil y se diseñan dos controladores PID para mantener el sistema estable. El primer controlador mantiene el péndulo en equilibrio verticalmente, mientras que el segundo permite que la base móvil se posicione en el centro del espacio determinado. También se ha generado una animación en 3 dimensiones con la que se observa claramente el comportamiento del sistema. En aquest projecte s'obté el model matemàtic del sistema no lineal format per un pèndul invertit sobre una base mòbil i es dissenyen dos controladors PID per mantenir el sistema estable. El primer controlador manté el pèndul en equilibri verticalment, mentre el segon permet que la base mòbil es posicioni al centre de l'espai determinat. També s'ha generat una animació en 3 dimensions amb la qual s'observa clarament el comportament del sistema. In this project the mathematical model of the non-linear system formed by an inverted pendulum on a mobile base is obtained and two PID controllers are designed to keep the system stable. The first controller keeps the pendulum in equilibrium vertically, while the second allows the moving base to be positioned in the centre of the given space. A 3-dimensional animation has also been generated that shows clearly the behaviour of the system.

In this paper, energy management and control of a microgrid is developed through supervisor and adaptive neuro?fuzzy wavelet?based control controllers considering real weather patterns and load variations. The supervisory control is applied to the entire microgrid using lower–top level arrangements. The top?level generates the control signals considering the weather data patterns and load conditions, while the lower level controls the energy sources and power converters. The adaptive neuro?fuzzy wavelet?based controller is applied to the inverter. The new proposed wavelet?based controller improves the operation of the proposed microgrid as a result of the excellent localized characteristics of the wavelets. Simulations and comparison with other existing intelligent controllers, such as neuro?fuzzy controllers and fuzzy logic controllers, and classical PID controllers are used to present the improvements of the microgrid in terms of the power transfer, inverter output efficiency, load voltage frequency, and dynamic response. © 2020 by the authors. Licensee MDPI, Basel, Switzerland. Ministerio de Ciencia, Innovación y Universidades, MCIU: RTI2018?095720?B?C32; Deutsche Forschungsgemeinschaft, DFG: 350746631; Türkiye Bilimsel ve Teknolojik Araştirma Kurumu, TÜBITAK: 5190011 Funding: The work of Murat Karabacak and Tariq Kamal is sponsored by the Scientific and Technological Research Council of Turkey under project number 5190011. The work of Vedran S. Peri? is supported by the Bavarian Government and Deutsche Forschungsgemeinschaft (DFG) under project number 350746631. The work of Luis M. Fernández?Ramírez and Tariq Kamal is sponsored by the Spanish Ministry of Science, Innovation, and Universities under project number RTI2018?095720?B?C32.

This paper makes the case that practical differentiation of measured state variables may be seen as an observation or estimation scheme for linear time invariant state space controllers. It is shown that, although not having the separation property, the estimation error of this scheme converges to zero if the resulting closed loop system is strictly stable. On the basis of this concept, it is shown that PID controllers may be interpreted as a special case of state space controllers endowed with differential observation. The interesting consequences of this interpretation are discussed., Fundação para a Ciência e Tecnologia within the R&D Units Project Scope: UIDB/00319/2020

In the constant search for efficient industrial processes to guarantee high reliability, its environment has frequently witnessed more robust controllers to deal better with complex processes. In this context, this work presents the design of a Fuzzy Controller, embedded in an Arduino Mega microcontroller. This project uses a Resistor-Capacitor circuit and a Direct Current motor to validate the fuzzy controller effectiveness and compare it with other control techniques: classical PID controller. In addition, it was considered the storage capacity of routines in the Arduino board, regarding the dynamic memory according to the increase of new membership functions and rules. The fuzzy controller was embedded, where satisfactory results were obtained when compared to a PID controller, taking non-intrusive performance indices as validation parameters.

WOS:000595801300011 Processes including one or more integrators in their transfer functions can frequently be encountered in industry. In this study, integral-proportional-derivative (I-PD) controllers are proposed to control these type of processes. Analytical and optimal tuning rules are derived to tune the I-PD controllers for setpoint tracking of integrating plus first order plus dead time (IFOPDT) processes and double IFOPDT processes. Optimal tuning rules for setpoint tracking are achieved by minimising time moment weighted integral performance criteria. Obtained I-PD tuning formulas are in terms of process' transfer function parameters, namely the gain, time delay and time constant. Simulation examples are given to demonstrate the use of the proposed method. Comparisons are provided to show the superior closed-loop performance of the proposed approach than existing proportional-integral-derivative and I-PD controller designing methods. In addition, the practical implementation of the proposed designing method is presented by controlling the position of a cart on an experimental setup.

The scientific community has recently seen a fast-growing number of publications tackling the topic of fractional-order controllers in general, with a focus on the fractional order PID. Several versions of this controller have been proposed, including different tuning methods and implementation possibilities. Quite a few recent papers discuss the practical use of such controllers. However, the industrial acceptance of these controllers is still far from being reached. Autotuning methods for such fractional order PIDs could possibly make them more appealing to industrial applications, as well. In this paper, the current autotuning methods for fractional order PIDs are reviewed. The focus is on the most recent findings. A comparison between several autotuning approaches is considered for various types of processes. Numerical examples are given to highlight the practicality of the methods that could be extended to simple industrial processes.

This paper elaborates the application of new nature inspired algorithm; ‘Whale Optimization Algorithm (WOA)’ in load frequency control of two area interconnected non-reheat thermal power plants. Two number of PID controllers have been considered in the investigated system and the parameters of the controllers have been tuned/optimized using WOA. The design problem has been formulated as the constrained optimization problem with upper and lower bounds of controller’s parameters. The integral of time multiplied absolute error (ITAE) has been taken as an objective function in the present work. The parameters of controllers (KP, KI, KD), minimum damping ratio (MDR), the values of performance indices (ITAE, ISTE, ISE, IAE), settling times and overshoots of Δf1, Δf2 and ΔPTie have also been evaluated for the system under investigation using WOA. The simulation results include the dynamic responses of Δf1, Δf2 and ΔPTie for different step load changes from 0.1p.u. to 0.5p.u in area 1 by keeping constant 0.1p.u. step load change in area 2. It has been observed that smooth and better dynamic responses with fewer oscillations, less settling times and less overshoots can be achieved for the system using WOA.

In this paper we propose a methodology to evaluate the performance of decentralized PID controllers for two-inputs-two-outputs processes and to retune the parameters. In particular, the model of the process is estimated based on a technique that exploits the final value theorem. Then, an evolutionary algorithm is applied in order to find the Pareto front by considering a multiobjective optimization problem. Finally, the performance obtained with the current tuning is compared with the optimal ones and, in case it is necessary, the PID parameters are retuned accordingly. A procedure to achieve the Nash optimal point is also proposed.

The production of recombinant proteins is gaining increasing importance as the market requests high quality proteins for several applications. However, several process parameters affect both the growth of cells and product yields. This study uses high throughput systems and statistical methods to assess the influence of fermentation conditions in lab-scale bioreactors. Using this methodology, it was possible to find the best conditions to produce cytochrome b5 with recombinant cells of Escherichia coli. Using partial least squares, the height-to-diameter ratio of the bioreactor, aeration rate, and PID controller parameters were found to contribute significantly to the final biomass and cytochrome concentrations. Hence, we could use this information to fine-tune the process parameters, which increased cytochrome production and yield several-fold. Using aeration of 1 vvm, a bioreactor with a height-to-ratio of 2.4 and tuned PID parameters, a production of 72.72 mg/L of cytochrome b5 in the culture media, and a maximum of product to biomass yield of 24.97 mg/g could be achieved.

In this paper a closed loop automatic tuning procedure for the velocity control of oscillatory mechatronic systems is proposed. The transfer function of the system is estimated relying only on the measurements on the motor side, resonances are identified and biquadratic filters and the PID controller are tuned in order to improve the pre-existing control system by reducing the oscillations on the load side. Experimental results obtained with a Hardware-In-the-Loop setup show the effectiveness of the method.

International audience; This paper focuses on the design of two different delay-based control schemes. These two low-complexity controllers are proposed as alternatives for the classical PD and PI controllers. More precisely, first, we study a PD controller using the Euler approach for approximating the derivative action. Second, we analyze the implications of imposing a delay in the error signal on the integral action of the PI controller for closed-loop response manipulation purposes. Our main contribution lies in proposing some practical guidelines for the tuning of these delayed control schemes such that the closed-loop system is stable. To this end, the criteria developed in this work makes use of the well-known D—partition method, with the difference that we propose a simple criterion to detect stabilizing regions, avoiding in this way the crossing direction analysis. Several numerical examples illustrate the effectiveness of the proposed approach.

Proportional–Integral–Derivative (PID) controllers with integral action are conventionally used as feedback controllers. They are used to obtain zero steady‐state error when the reference input or the disturbance are steps and where zero‐type systems (i.e. with no poles at the origin) are controlled. The controller meets its objective when the controlled system is non linear, but usually introduces undesirable changes in the dynamics that must be compensated by readjusting the proportional gain. In this paper, we compare PID with two alternative techniques based on the use of a feed‐forward system and a multiple feedback system, respectively. A detailed comparison of the transient response obtained with these methods is presented and validated with some simulation examples., This research is in receipt of funding from the Spanish Ministry of Science, Innovation and Universities (COG-DRIVE project: Artificial Intelligence Techniques and Assistance to Autonomous Navigation, reference DPI2017-86915-C3-3-R). It has also received funding from the RoboCity2030-DIH-CM Madrid Robotics Digital Innova-tion Hub project (Robótica aplicada a la mejora de la cali-dad de vida de los ciudadanos. fase IV; S2018/NMT-4331),funded by Programas de Actividades I+D en la Comunidad de Madrid and cofunded through EU Structural Funds

O consumo de energia elétrica vem aumentando. Esse crescimento estimula a produção que está inteiramente baseada em combustíveis fósseis. Entretanto, por razoes sociais, políticas ou ambientais há uma necessidade de mudar a fonte energética. A geração em larga, média e baixa escala por meio de turbinas eólicas é uma solução viável. Similar a outros métodos de geração, a turbina eólica precisa ser otimizada e controlada para funcionar da forma mais eficiente possível. Nesse trabalho um processo de otimização por enxame de partículas otimizou um perfil de uma turbina eólica baseado em duas equações de esticão que tinha como objetivo o melhor coeficiente de potência para a velocidade média. Também utilizou um controlador neuro fuzzy com base nos máximos para cada razão entre velocidades (). Três perfis de velocidade de vento foram usados para analisar a dinâmica da turbina eólica. O controlador se mostrou eficiente e manteve a rotação dentro da faixa esperada. Os resultados mostram que o controlador preveniu a geração acima da potência máxima, reduzindo a rotação em até 12 [rad/s] acima da potência máxima, em casos de oscilação na velocidade do vendo o controle se manteve estável com um baixo desvio padrão e reduzindo a potência em ao em até 8 [rad/s] para ondas senoidal e em até 9 [rad/s] para entradas aleatórias. The consumption of electric energy is increasing. This growth stimulates production that is entirely based on fossil fuels. However, for social, political or environmental reasons there is a need to change the energy source. Large, medium and low-scale generation by means of wind turbines is a viable solution. Similar to other generation methods, the wind turbine needs to be optimized and controlled to function as efficiently as possible. In this work a particle swarm optimization process optimized a profile of a wind turbine based on two stretching equations that had as objective the best coefficient of power for the average speed. We also used a fuzzy neuro controller based on the maximum for each ratio between speeds (). Three wind speed profiles were used to analyze the dynamics of the wind turbine. The controller was efficient and kept the rotation within the expected range. The results show that the controller prevented the generation above the maximum power, reducing the rotations by up to 12 [rad/s] above the maximum power, in cases of oscillation in the velocity of the view the control remained stable with a low standard deviation and reducing the power in at up to 8 [rad/s] for sine waves and up to 9 [rad/s] for random inputs.

Brushless DC (BLDC) motor is commonly employed for many industrial applications due to their high torque and efficiency. This article produces an optimal designed controller of Brushless DC motor speed control depending on the genetic algorithm (GA). The optimization method is used for searching of the ideal Proportional–Integral-Derivative (PID) factors. The controller design methods of brushless DC motor includes three kinds: trial and error PID design, auto-tuning PID design and genetic algorithm based controller design. A PID controller is utilizing by conducted Integral absolute error criterion (IAE) and integral squared error (ISE) error criterion for BLDC motor control system. A GA-PID controller is designed to enhance the system performance by means of genetic algorithm. PID controller coefficients(Kp, Ki and Kdare calculated by GA to produce optimal PID as hybrid PID with GA controller .The closed loop speed response of PID controller is experimented for IAE and ISE error criteria. The suggested controller GA_PID is planned, modeled and simulated by MATLAB/ software program. A comparison output system performance monitored for every controller schemes. The results display that the time characteristics performance of GA-PID controller based on ISE objective function has the optimal performance (rise time, settling time, percentage overshoot) with other techniques.

Submitted by Sheila MONTEIRO (sheila.monteiro@ufma.br) on 2019-10-09T19:25:19Z No. of bitstreams: 1 JOSÉ-MOURA.pdf: 13644018 bytes, checksum: 9cdc55305eb492d4a01786ce4dce94c6 (MD5) Made available in DSpace on 2019-10-09T19:25:19Z (GMT). No. of bitstreams: 1 JOSÉ-MOURA.pdf: 13644018 bytes, checksum: 9cdc55305eb492d4a01786ce4dce94c6 (MD5) Previous issue date: 2019-03-21 Optimal online tuning of industrial process controls is an activity that requires the development of dedicated hardware and software for controller parameter setting activity in manufacturing plants that assist in achieving the goals to be achieved in a relatively short time. contributing to the technological evolution of industry 4.0, which lead to an autonomous tuning of industrial processes. In order to support tuning of control systems that follow design approaches such as model-based control (MBC) or datadriven control (DDC), proposed methodologies for online tuning for model-based PID controllers are: Neuro-Fuzzy and guided by sensor data. This Doctoral Thesis presents innovative methodologies for controlling the operational processes of industrial systems with application in mining sector equipment to be embedded in Programmable Logic Controllers (PLC). For better understanding, this Thesis is divided into two parts, where Part I - gives an overview of the industrial process, addressing each of the process phases and a brief introduction to programmable logic controllers. The theoretical framework of proportional, integral and derivative actions (PID), Adaptive Dynamic Programming (ADP) and Computational Intelligence (CI) are presented for the theoretical basis, formulation and problem solving presented in this Thesis. Finally, the proposed methodology is presented. Already in the textbf Part II - we present the Tuning Models Online MBC and DDC of Industrial Processes in two approaches, being: a) Plant model dependent - represented in state spaces and transfer functions, designed with real process data for automatic adjustment of PID controller gains. This adjustment is made as follows: at first, optimal PID controller gains are determined offline through a structured artificial neural network and then a fuzzy rules-based system is used to adjust earnings through a scaling scheme online of this gains vector. In the second moment, the optimal PID controller gains are determined online through a structured feed-forward artificial neural network with low computational complexity training algorithms and high performance RLS algorithms and b) Independent of plant models - taking into account only sensor input/output state signals measured by sensors. Also in this context, an optimal tuning methodology for self-adjusting gain controllers based on Quadratic Linear Regulator (RLQ) (continuous time / discrete time) is presented in Approximate Dynamic Programming (PDA), specifically Action-Dependent Adaptive Heuristic Dynamic Programming (AD-AHDP) has been applied to the experiments presented in this Thesis. A sintonia online e ótima de controles de processos industriais é uma atividade que requer o desenvolvimento de hardware e software dedicados para a atividade de ajustes de parâmetros de controladores em plantas industriais, que auxiliam no alcance das metas a serem atingidas em um espaço de tempo relativamente pequeno contribuindo com a evolução tecnológica da industria 4.0, que conduzem a uma sintonia autônoma dos processos industriais. No sentido de dar suporte para a sintonia de sistemas de controle que seguem abordagens de projeto dos tipos: model-base control (MBC) ou data-driven control (DDC), são metodologias propostas para sintonia online e ótima para controladores PID que são baseadas em modelos Neuro-Fuzzy e guiadas por dados de sensores. Nesta Tese de Doutorado apresenta-se metodologias inovadoras para controle de processos operacionais de sistemas industriais com aplicação em equipamentos do setor de mineração para serem embarcados em controladores lógicos programáveis (CLP). Para melhor entedimento, esta Tese está dividida em duas partes, onde na Parte I - faz-se a descrição geral do processo industrial, abordando-se cada uma das fases do processo e uma breve introdução sobre controladores lógicos programáveis. Apresenta-se o referencial teórico das ações proporcionais, integrais e derivativas (PID), programação dinâmica adaptativa (PDA) e inteligência computacional (IC) para o embasamento teórico, formulação e solução de problemas apresentados nesta Tese. Por fim, é apresentada a metodologia proposta. Já na Parte II - apresenta-se os modelos de sintonia online e ótima MBC e DDC de processos industriais em duas abordagens, sendo: a) Dependente de modelos da planta - representado em espaços de estado e funções de transferências (FTs), concebidos com dados reais dos processos para ajuste automático de ganhos de controladores PID. Este ajuste é feito da seguinte forma, no primeiro momento, os ganhos ótimos do controlador PID são determinados offline por meio de uma rede neuronal artificial estruturada (RNA-E) e em seguida, um sistema baseado em regras fuzzy é usado para fazer o ajuste dos ganhos por meio de um esquema de escalonamento online desse vetor de ganhos. No segundo momento, os ganhos ótimos do controlador PID são determinados online por meio de uma RNA-E do tipo feed-forward com algoritmos de treinamento com baixa complexidade computacional e algoritmos baseados em regulador linear quadrático (RLQ) com alto desempenho e b) Independente de modelos da planta - levando-se em conta, somente os sinais dos estados de entradas/saídas da planta medidos por sensores. Ainda neste contexto, apresenta-se uma metodologia de sintonia ótima de controladores com ganhos autoajustáveis por controle com base em RLQ (tempo contínuo/tempo discreto), em PDA, especificamente a programação dinâmica heurística aproximada/adaptativa dependente de ação (PDHADA) que foi aplicada nos experimentos apresentados nesta Tese.

International audience; Walking ability can be lost due to several neurological diseases. In this paper, we are interested in the rehabilitation of pediatric patients. For this purpose, an extended L 1 adaptive control has been proposed to control 2 DOF lower limbs exoskele-tons used to rehabilitate kids suffering from Cerebral Palsy (CP). Two methods based on PID controllers have been combined with L 1 adaptive control in order to ensure the limb movement along a predefined trajectory. Then, a comparison study has been established based on tracking errors. Moreover, to improve the robustness of these controllers against uncertainties , several tests with the variations of children masses and lengths have been carried out, with the presence of torque limits using fuzzy logic.

Submitted by Julia CTC/B (julia.vieira@uerj.br) on 2021-12-07T18:47:43Z No. of bitstreams: 1 Dissertação - Paulo Roberto Souza da Paz - 2019 - Completo.pdf: 6107731 bytes, checksum: 19410c196b2fa7c1227f8b872872ce40 (MD5) Made available in DSpace on 2021-12-07T18:47:43Z (GMT). No. of bitstreams: 1 Dissertação - Paulo Roberto Souza da Paz - 2019 - Completo.pdf: 6107731 bytes, checksum: 19410c196b2fa7c1227f8b872872ce40 (MD5) Previous issue date: 2019-02-27 Deterministic and Stochastic Extremum Seeking (ES) approaches are employed to adapt the gains of a Proportional-Integral-Derivative (PID) control law for functional neuromuscular electrical stimulation (NMES). The proposed scheme are applied to control the position of the arm of healthy volunteers and stroke patients so that coordinated movements of flexion/extension for their elbow can be performed. This approach eliminates the initial tuning tests with patients since the controller parameters are automatically computed in real time. The PID controller parameters are updated by means of a discrete version of multivariable ES in order to minimize a cost function which brings the desired performance requirements. Experimental results with healthy volunteers as well as stroke patients show the usual specifications commonly considered in physiotherapy for functional rehabilitation are eventually satisfied in terms of steady-state error, settling time, and percentage overshoot. Quantitative results show a reduction of 65, 50% in terms of the root-mean-square error (RMSE) – from 11, 65º−to 4, 02º−– when comparing the tracking curves of the last cycle to the first cycle in the experiments with all subjects. A técnica de Busca Extremal (Extremum Seeking - ES) nas versões determinística e estocástica são aplicadas para adaptar os ganhos de um controlador Proporcional-Integral- Derivativo (PID) na estimulação elétrica neuromuscular. Os esquemas propostos são aplicados no controle da posição do braço de pacientes com sequelas de Acidente Vascular Cerebral (AVC) para coordenar os movimentos de flexão e extensão dos braços. Esta abordagem elimina os testes iniciais de sintonia e os parâmetros do controlador são automaticamente computados em tempo real. Os parâmetros do controlador PID são ajustados através de uma versão discreta multivariável dos algoritmos de ES para minimizar uma função de custo que representa o desempenho dos requisitos desejados. Resultados experimentais com pacientes com AVC mostram que as especificações geralmente consideradas na fisioterapia para reabilitação funcional são satisfeitas em termos de erro estacionário, tempo de assentamento e percentual de ultrapassagem. Resultados quantitativos apresentam uma redução de 65, 50% no erro médio quadrático (Root Mean Square Error - RMSE) – de 11, 65º−para 4, 02º−quando comparado o primeiro e último ciclo nos experimentos com todos os indivíduos.

Typically, disassembly forces are unknown due to high forces or high temperatures during product operation, where assembly connections solidify. For the regulation of disassembly forces a controller is developed. The controller is formed for two steps: The first step is a PID controller that produces a force, which overcomes a solidifying force slightly. The second step is a vibration controller with a FM modulation to regulate the frequency of impacts. Vibrations are useful for decreasing the force amplitude for caring the joined components. Finally, the control is validated with disturbances in a simulation. © 2019 The Author(s).

In this paper an automatic tuning procedure for a cascade position control architecture of general mechatronic systems is presented. The proposed procedure firstly estimates the transfer function of the system by analysing its open-loop response to a signal specifically designed in order to satisfy the system position, velocity and torque constraints. Then, if present, oscillatory behaviours are detected by finding the (anti)resonances of the frequency response. Parametric tuning rules are eventually defined for the PID controllers and for the biquadratic filters. Results obtained by implementing the procedure on a Hardware In the Loop setup demonstrate the effectiveness of the method.

Directora: Gemma Fargas This thesis is written as part of the “Smart Load” project, which has as aim the research of new methods to reinforce the reliability in high-automatized electric vehicles. The results of the work are developed on the basis of a demonstrator vehicle that was used in “e2 -Lenk” project, where the steering system could be manual or remote actuated. Motors worked as steering assistance and had to provide a specific torque. Now they work as steering actuators and have to provide a specific angle. Therefore, the design of a new controller is one of the necessary adjustments to allow the autonomous driving of the car in the next steps of the project. First of all the adaptation and extension of the vehicle´s virtual model on SIMULINK was necessary. A low order model of the steering system, including friction, inertias and play is developed and some structures are redesigned. A PID controller is designed and implemented in order to achieve a desired steering wheel angle through the action of three available actuators: two redundant actuators at the steering column and the distribution of front wheel torques. The controller is tuned to work properly with the whole range of speeds and torque allocations. The performance of the model and the controller are evaluated in IPG CARMAKER software through the simulation of the vehicle along different standardized maneuvers to analyze the steering response and the overall stability of the car. Although some perturbations are observed in the torque distribution, an overall stability of the whole vehicle in the different tests is achieved.

WOS: 000491169100006, Purpose The purpose of this paper is to rise the autonomous flight performance of the small unmanned aerial vehicle (UAV) using simultaneous tailplane of UAV and autopilot system design. Design/methodology/approach A small UAV is remanufactured in the UAV laboratory. Its tailplane can be changed before the flight. Autopilot parameters and some parameters of tailplane are instantaneously designed to maximize autonomous flight performance using a stochastic optimization method. Results found are applied for simulations. Findings Benefitting simultaneous tailplane of UAV and autopilot system design process, autonomous flight performance is maximized. Research limitations/implications - Authorization of Directorate General of Civil Aviation in Turkey is required for UAV flights. Practical implications - Simultaneous tailplane and autopilot system design process is so useful for refining UAV autonomous flight performance. Social implications - Simultaneous tailplane and autopilot system design process fulfills confidence, high autonomous performance, and easy service demands of UAV users. By that way, UAV users will be able to use better UAVs. Originality/value Creating a novel technique to recover autonomous flight performance (e.g. less overshoot, less settling time and less rise time during trajectory tracking) of UAV and developing a novel procedure performing simultaneous tailplane of UAV and autopilot system design idea., Research Fund of Erciyes University Scientific Research Projects (BAP) Coordination Unit [FBA-2018-6712]; Research Fund of The Scientific and Technological Research Council of Turkey (TUBITAK)Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [114M856], This work was supported by the Research Fund of Erciyes University Scientific Research Projects (BAP) Coordination Unit under Project Number: FBA-2018-6712.; This work was also supported by the Research Fund of The Scientific and Technological Research Council of Turkey (TUBITAK) under Project Number: 114M856.; The author would like to also recognize Assoc. Prof. Dr Tugrul OKTAY, Assist. Prof. Dr Mehmet KONAR and PhD Candidate Alpertunga CEYLAN for their supports during UAV manufacturing and UAV flight testing.