Дисертації з теми "Control-based design"

Il est bien connu que les robots parallèles ont de nombreuses applications dans l ’industrie. Cependant, en raison de leur structure complexe, leur contrôle peut être difficile. Lorsqu'une précision élevée est nécessaire , un modèle complet du robot détaillé est nécessaire . Les approches de contrôle référencées capteurs se sont avérées plus efficaces , en termes de précision que les contrôleurs basés modèles puisqu'elles s’affranchissent des modèles de robots complexes et des erreurs de modélisation associées. Néanmoins, lors de l'application de d’un asservissement visuel , il y a toujours des problèmes dans le processus de contrôle , tels que les singularités du contrôleur . Cette thèse propose une méthodologie de conception orientée commande qui prend en compte les performances de précision du contrôleur dans le processus de conception du robot pour obtenir les paramètres géométriques optimaux de ce dernier Trois contrôleurs ont été sélectionnés dans le processus de conception du robot : les commandes basées sur l’observation des directions des jambes, les commandes basées sur l’observation des lignes et les commandes basées sur des moments dans l'image .Pour vérifier les performances en terme de précision des robots optimisés, nous avons effectué des co-simulations des robots optimisés avec les contrôleurs correspondants . En terme d’expérimentation, deux prototypes de robots DELTA ont été conçus et expérimentés afin de valider la précision du contrôleur
It is well -known that parallel robots have a lot of applications in industry for their high stiffness , high payload , can reach higher acceleration and speed . However , because of their complex structure , their control may be troublesome. When high accuracy is needed, the detailed robot model is necessary . However , even detailed models still suffer from the problem of inaccuracy in reality because of robot assembly and manufacturing errors . Sensor - based control approaches have been proven to be more efficient than model-based controllers in terms of accuracy since they overcome the complex robot models and inconsistency errors. Nevertheless, when applying the visual servoing, there are always some problems in the control process , such as the controller singularities . Thus , this thesis proposes proposes a control based design metodology which takes into account the accuracy performance of the controller in the design process to get the geometric parameters of the robot. This thesis applied the control-based design methodology to the optimal design of three types of parallel robots: Five-bar mechanisms , DELTA robots , Gough -Stewart platforms . Three types of controllers are selected in the design process : leg -direction -based visual servoing, line-baesd visual servoing and image moment visual servoing . Design optimization problems are formulated to find the geometric parameters of the robot . Co-simulations are performed to check the accuracy performance of the robots obtained from the optimization. Experiments are performed with two DELTA robot prototypes in order to validate the controller accuracy

This thesis mainly focuses on two Internet based control applications. One is a networked control system (NCS) where the control loop is closed through the network. The other is the Networked Control System Laboratory (NCSLab) which is a global web based remote experimentation platform. The contribution in the first part of the thesis relates to the networked predictive control (NPC) which was first introduced by Liu et al. (2004). In this method, the controller uses the model predictive approach to predict a future control sequence and send it to the plant in a network packet. The plant side receives this packet and then determine the appropriate control signal to apply to the actuator according to the time delay measurement. This method is innovative and works well in theory, but it has two deficiencies in practical applications. The first deficiency is that it needs synchronization between the controller and plant side to measure the individual forward and feedback channel time delays and this is very hard to achieve on the Internet. In this thesis, a round-trip NPC is proposed in which the predictive calculations and signal selections are based on the round-trip delay. The measurement of the round-tip delay is achieved using the plant side clock only, so that the need for synchronization is avoided. The second deficiency is that the mathematical model has to be accurately known. Otherwise the accuracy of the predictive calculation is affected, which may result in a degraded control performance. An event-driven NPC scheme is introduced to solve this problem. In this scheme, the selection of the appropriate control signal is not based on the time delay measurement but on the previous system output. This method can compensate for the effect of model uncertainty, which has been verified by both simulations and real-time experiments. Some experiments carried out on other NPC schemes are also reported on in this thesis. They are the NPC in state-space form and nonlinear NPC. These methods expand the use of NPC methodology. The second part of the thesis describes the design and implementation of the Networked Control System Laboratory. The NCSLab is based in the University of Glamorgan but its test rigs are diversely located in four Institutions from both the UK and China. In order to manage these test rigs from different places, a four layer structure (Central Server/Regional Server/Sub-Server/Test Rig) is adopted. The four layers are integrated into one system via the Internet. In order to deliver the remote experimentation to the users, a web-based user interface is designed. It provides great flexibility to the users such as remote monitoring, remote tuning and remote control algorithms. The implementation of the user interface (UI) heavily adopts the AJAX technology, so the remote experiments can be conducted inside the web browsers without installing special plug-ins. In order to show how the NCSLab works, two examples are given in the thesis.

付記する学位プログラム名: デザイン学大学院連携プログラム
Kyoto University (京都大学)
0048
新制・課程博士
博士(工学)
甲第21761号
工博第4578号
新制||工||1713(附属図書館)
京都大学大学院工学研究科航空宇宙工学専攻
(主査)教授 藤本 健治, 教授 泉田 啓, 教授 太田 快人
学位規則第4条第1項該当

This thesis presents a model for the ACK-clock inner loop, common to virtually all Internet congestion control protocols, and analyzes the stability properties of this inner loop, as well as the stability and fairness properties of several window update mechanisms built on top of the ACK-clock. Aided by the model for the inner-loop, two new congestion control mechanisms are constructed, for wired and wireless networks. Internet traffic can be divided into two main types: TCP traffic and real-time traffic. Sending rates for TCP traffic, e.g., file-sharing, uses window-based congestion control, and adjust continuously to the network load. The sending rates for real-time traffic, e.g., voice over IP, are mostly independent of the network load. The current version of the Transmission Control Protocol (TCP) results in large queueing delays at bottlenecks, and poor quality for real-time applications that share a bottleneck link with TCP. The first contribution is a new model for the dynamic relationship between window sizes, sending rates, and queue sizes. This system, with window sizes as inputs, and queue sizes as outputs, is the inner loop at the core of window-based congestion control. The new model unifies two models that have been widely used in the literature. The dynamics of this system, including the static gain and the time constant, depend on the amount of cross traffic which is not subject to congestion control. The model is validated using ns-2 simulations, and it is shown that the system is stable. For moderate cross traffic, the system convergence time is a couple of roundtrip times. When introducing a new congestion control protocol, one important question is how flows using different protocols share resources. The second contribution is an analysis of the fairness when a flow using TCP Westwood+ is introduced in a network that is also used by a TCP New Reno flow. It is shown that the sharing of capacity depends on the buffer size at the bottleneck link. With a buffer size matching the bandwidth-delay product, both flows get equal shares. If the buffer size is smaller, Westwood+ gets a larger share. In the limit of zero buffering, it gets all the capacity. If the buffer size is larger, New Reno gets a larger share. In the limit of very large buffers, it gets 3/4 of the capacity. The third contribution is a new congestion control mechanism, maintaining small queues. The overall control structure is similar to the combination of TCP with Active Queue Management (AQM) and explicit congestion notification, where routers mark some packets according to a probability which depends on the queue size. The key ideas are to take advantage of the stability of the inner loop, and to use control laws for setting and reacting to packet marks that result in more frequent feedback than with AQM. Stability analysis for the single flow, single bottleneck topology gives a simple stability condition, which can be used to guide tuning. Simulations, both of the fluid-flow differential equations, and in the ns-2 packet simulator, show that the protocol maintains small queues. The simulations also indicate that tuning, using a single control parameter per link, is fairly easy. The final contribution is a split-connection scheme for downloads to a mobile terminal. A wireless mobile terminal requests a file from a web server, via a proxy. During the file transfer, the Radio Network Controller (RNC) informs the proxy about bandwidth changes over the radio channel, and the current RNC queue length. A novel control mechanism in the proxy uses this information to adjust the window size. In simulation studies, including one based on detailed radio-layer simulations, both the user response time and the link utilization are improved, compared TCP New Reno, Eifel and Snoop, both for a dedicated channel, and for the shared channel in High-Speed Downlink Packet Access.
QC 20100830

Development of modern aircraft has become more and more expensive and time consuming. In order to minimize the development cost, an improvement of the conceptual design phase is needed. The desired goal of the project is to enhance the functionality of an in house produced framework conducted at the department of machine design, consisting of parametric models representing a large variety of aircraft concepts.

The first part of the work consists of the construction of geometric aircraft control surfaces such as flaps, aileron, rudder and elevator parametrically in CATIA V5.

The second part of the work involves designing and simulating an Inverse dynamic model in Dymola software.

An Excel interface has been developed between CATIA and Dymola. Parameters can be varied in the interface as per user specification; these values are sent to CATIA or Dymola and vice versa. The constructed concept model of control surfaces has been tested for different aircraft shapes and layout. The simulation has been done in Dymola for the control surfaces.

In this dissertation. we document the progress in the control design for a class of MIMO nonlinear uncertain system from five papers. In the first part, we address the problem of adaptive control design for a class of multi-input multi-output (MIMO) nonlinear systems. A Lypaunov based singularity free control law, which compensates for parametric uncertainty in both the drift vector and the input gain matrix, is proposed under the mild assumption that the signs of the leading minors of the control input gain matrix are known. Lyapunov analysis shows global uniform ultimate boundedness (GUUB) result for the tracking error under full state feedback (FSFB). Under the restriction that only the output vector is available for measurement, an output feedback (OFB) controller is designed based on a standard high gain observer (HGO) stability under OFB is fostered by the uniformity of the FSFB solution. Simulation results for both FSFB and OFB controllers demonstrate the efcacy of the MIMO control design in the classical 2-DOF robot manipulator model. In the second part, an adaptive feedback control is designed for a class of MIMO nonlinear systems containing parametric uncertainty in both the drift vector and the input gain matrix, which is assumed to be full-rank and non-symmetric in general. Based on an SDU decomposition of the gain matrix, a singularity-free adaptive tracking control law is proposed that is shown to be globally asymptotically stable (GAS) under full-state feedback. Output feedback results are facilitated via the use of a high-gain observer (HGO). Under output feedback control, ultimate boundedness of the error signals is obtained the size of the bound is related to the size of the uncertainty in the parameters. An explicit upper bound is also provided on the size of the HGO gain constant. In third part, a class of aeroelastic systems with an unmodeled nonlinearity and external disturbance is considered. By using leading- and trailing-edge control surface actuations, a full-state feedforward/feedback controller is designed to suppress the aeroelastic vibrations of a nonlinear wing section subject to external disturbance. The full-state feedback control yields a uniformly ultimately bounded result for two-axis vibration suppression. With the restriction that only pitching and plunging displacements are measurable while their rates are not, a high-gain observer is used to modify the full-state feedback control design to an output feedback design. Simulation results demonstrate the ef cacy of the multi-input multioutput control toward suppressing aeroelastic vibration and limit cycle oscillations occurring in pre and post utter velocity regimes when the system is subjected to a variety of external disturbance signals. Comparisons are drawn with a previously designed adaptive multi-input multi-output controller. In the fourth part, a continuous robust feedback control is designed for a class of high-order multi-input multi-output (MIMO) nonlinear systems with two degrees of freedom containing unstructured nonlinear uncertainties in the drift vector and parametric uncertainties in the high frequency gain matrix, which is allowed to be non-symmetric in general. Given some mild assumptions on the system model, a singularity-free continuous robust tracking control law is designed that is shown to be semi-globally asymptotically stable under full-state feedback through a Lyapunov stability analysis. The performance of the proposed algorithm have been verified on a two-link robot manipulator model and 2-DOF aeroelastic model.
ID: 031001394; System requirements: World Wide Web browser and PDF reader.; Mode of access: World Wide Web.; Title from PDF title page (viewed May 28, 2013).; Thesis (Ph.D.)--University of Central Florida, 2011.; Includes bibliographical references (p. 80-83).
Ph.D.
Doctorate
Electrical Engineering and Computer Science
Engineering and Computer Science
Electrical Engineering

In this dissertation. we document the progress in the control design for a class of MIMO nonlinear uncertain system from five papers. In the first part, we address the problem of adaptive control design for a class of multi-input multi-output (MIMO) nonlinear systems. A Lypaunov based singularity free control law, which compensates for parametric uncertainty in both the drift vector and the input gain matrix, is proposed under the mild assumption that the signs of the leading minors of the control input gain matrix are known. Lyapunov analysis shows global uniform ultimate boundedness (GUUB) result for the tracking error under full state feedback (FSFB). Under the restriction that only the output vector is available for measurement, an output feedback (OFB) controller is designed based on a standard high gain observer (HGO) — stability under OFB is fostered by the uniformity of the FSFB solution. Simulation results for both FSFB and OFB controllers demonstrate the ef?cacy of the MIMO control design in the classical 2-DOF robot manipulator model. In the second part, an adaptive feedback control is designed for a class of MIMO nonlinear systems containing parametric uncertainty in both the drift vector and the input gain matrix, which is assumed to be full-rank and non-symmetric in general. Based on an SDU decomposition of the gain matrix, a singularity-free adaptive tracking control law is proposed that is shown to be globally asymptotically stable (GAS) under full-state feedback. Output feedback results are facilitated via the use of a high-gain observer (HGO). Under output feedback control, ultimate boundedness of the error signals is obtained &"241; the size of the bound is related to the size of the uncertainty in the parameters. An explicit upper bound is also provided on the size of the HGO gain constant. In third part, a class of aeroelastic systems with an unmodeled nonlinearity and external disturbance is considered. By using leading- and trailing-edge control surface actuations, a full-state feedforward/feedback controller is designed to suppress the aeroelastic vibrations of a nonlinear wing section subject to external disturbance. The full-state feedback control yields a uniformly ultimately bounded result for two-axis vibration suppression. With the restriction that only pitching and plunging displacements are measurable while their rates are not, a high-gain observer is used to modify the full-state feedback control design to an output feedback design. Simulation results demonstrate the ef ? cacy of the multi-input multi-output control toward suppressing aeroelastic vibration and limit cycle oscillations occurring in pre and post? utter velocity regimes when the system is subjected to a variety of external disturbance signals. Comparisons are drawn with a previously designed adaptive multi-input multi-output controller. In the fourth part, a continuous robust feedback control is designed for a class of high-order multi-input multi-output (MIMO) nonlinear systems with two degrees of freedom containing unstructured nonlinear uncertainties in the drift vector and parametric uncertainties in the high frequency gain matrix, which is allowed to be non-symmetric in general. Given some mild assumptions on the system model, a singularity-free continuous robust tracking control law is designed that is shown to be semi-globally asymptotically stable under full-state feedback through a Lyapunov stability analysis. The performance of the proposed algorithm have been verified on a two-link robot manipulator model and 2-DOF aeroelastic model.
Ph.D.
Doctorate
Electrical Engineering and Computer Science
Engineering and Computer Science
Electrical Engineering

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2010.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. 209-219).
This thesis deals with the design and control of flexure-based mechanisms for applications requiring multi-degree-of-freedom positioning and alignment. Example applications include positioning a probe or sample in atomic force microscopy, alignment of tool and sample in stamping processes, and fine-positioning of wafer steppers in semiconductor manufacturing. Such applications necessitate nanopositioning systems that satisfy critical functional requirements, such as load-capacity, bandwidth, resolution, and range. Therefore, a systematic approach for design and control is an important tool for research and development for flexure-based nanopositioning systems. In this thesis, a novel methodology is presented for generating flexure-based topologies that can meet performance requirements, such as those dictating structural strength or dynamical behavior. We present performance metrics that allow for the generation of topologies that are tuned for a desired level of structural strength or modal separation. The topology generation is aimed as a valuable addition to the design toolkit, facilitating novel designs that could not have been conceived otherwise. The parameters within any particular topology could be adjusted at a subsequent phase through a detailed shape and size optimization. The thesis also proposes a controller generation approach. Unlike existing controller parameterizations, a novel parameterization formulated in this thesis allows for directly tuning the sensitivity transfer function of the closed-loop system. Tuning sensitivity is critical in mitigating the effects of disturbances affecting the system, as well as those arising from cross-coupling and parasitic error motions. Further, an integrated methodology for design and control is presented. This methodology uses the design topology generation approach and controller generation approach proposed in the thesis. The key distinction of our design for control approach is that the design is iterated over topologies and not just parameters within a selected topology. A simple one-degree-of-freedom positioning system example is worked out to detail the steps of the proposed integrated design and control methodology. A novel design topology that is ideally suited for achieving a desired design and control performance is derived using this methodology. Finally, the hardware design and control of a novel flexure-based nanopositioner implementation for scanning probe microscopy are presented to illustrate the effectiveness of the approaches discussed in this thesis.
by Vijay Shilpiekandula.
Ph.D.

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CAPES
A number of approaches have been proposed for eliciting, modeling and analyzing requirements for adaptive systems. However, there is still a large gap between such requirements specifications and the actual implementation of adaptive systems. In this thesis we investigate the interplay between requirements and architecture for the development of adaptive systems. Furthermore, we propose the Multi-Level Adaptation for Software Systems (MULAS) framework. This framework is centered on the iterative and incremental refinement of a goal model, towards the creation of a Design Goal Model. This model can then be used at runtime to drive adaptation on a system that is properly instrumented. Moreover, the framework includes a toolsupported process for generating statechart behavioral models from a Design Goal Model. The GATO tool (Goal TO Architecture) allows the creation of the different artifacts of the process, including the automatic generation of base statecharts. The suitability of this approach for developing adaptive systems is illustrated by means of case studies. Empirical results show that the techniques developed to translate enriched goal models onto statecharts are scalable, i.e. they present a good performance even with large models. Furthermore, an experiment with software engineering students indicates that the adoption of this framework by non-experts is feasible and beneficial.
Um grande número de abordagens foram propostas para elicitar, modelar e analisar requisitos para sistemas adaptativos. No entanto, ainda existe uma grande distância entre a especificação de requisitos e a implementação de um sistema adaptativo. Nesta tese foi investigada a interrelação entre requisitos e arquitetura para o desenvolvimento de sistemas adaptativos. Mais especificamente, nós propomos o framework Adaptação Multi-Nível para Sistemas de Software (MULAS, do inglês Multi-Level Adaptation for Software Systems). Este framework é focado no refinamento iterativo e incremental de um modelo de objetivos, em direção à criação de um Modelo de Objetivos de Design (DGM, do inglês Design Goal Model). Este modelo pode então ser utilizado em tempo de execução para se gerenciar a adaptação em um sistema devidamente instrumentado. Ademais, o framework inclui um processo para gerar diagramas de estados a partir do Modelo de Objetivos de Design. Uma ferramenta desenvolvida especificamente para apoiar este framework (GATO, do inglês, Goal TO Architecture) permite criar os diferentes artefatos do processo, incluindo a geração automática de diagrama de estados base. A adequação desta abordagem ao desenvolvimento de sistemas adaptativos é ilustrada através de estudos de caso. Resultados empíricos mostram que as técnicas desenvolvidas para criar diagramas de estados a partir do modelo de objetivos com elementos de design apresentam boa escalabilidade, i.e. possui bom desempenho mesmo no caso de modelos extensos. Adicionalmente, um experimento com estudantes de engenharia de software indica que a adoção do framework por não-especialistas não é apenas possível como também é benéfica.

Doutoramento em Engenharia Electrotécnica
The expectations of citizens from the Information Technologies (ITs) are increasing as the ITs have become integral part of our society, serving all kinds of activities whether professional, leisure, safety-critical applications or business. Hence, the limitations of the traditional network designs to provide innovative and enhanced services and applications motivated a consensus to integrate all services over packet switching infrastructures, using the Internet Protocol, so as to leverage flexible control and economical benefits in the Next Generation Networks (NGNs). However, the Internet is not capable of treating services differently while each service has its own requirements (e.g., Quality of Service - QoS). Therefore, the need for more evolved forms of communications has driven to radical changes of architectural and layering designs which demand appropriate solutions for service admission and network resources control. This Thesis addresses QoS and network control issues, aiming to improve overall control performance in current and future networks which classify services into classes. The Thesis is divided into three parts. In the first part, we propose two resource over-reservation algorithms, a Class-based bandwidth Over-Reservation (COR) and an Enhanced COR (ECOR). The over-reservation means reserving more bandwidth than a Class of Service (CoS) needs, so the QoS reservation signalling rate is reduced. COR and ECOR allow for dynamically defining over-reservation parameters for CoSs based on network interfaces resource conditions; they aim to reduce QoS signalling and related overhead without incurring CoS starvation or waste of bandwidth. ECOR differs from COR by allowing for optimizing control overhead minimization. Further, we propose a centralized control mechanism called Advanced Centralization Architecture (ACA), that uses a single state-full Control Decision Point (CDP) which maintains a good view of its underlying network topology and the related links resource statistics on real-time basis to control the overall network. It is very important to mention that, in this Thesis, we use multicast trees as the basis for session transport, not only for group communication purposes, but mainly to pin packets of a session mapped to a tree to follow the desired tree. Our simulation results prove a drastic reduction of QoS control signalling and the related overhead without QoS violation or waste of resources. Besides, we provide a generic-purpose analytical model to assess the impact of various parameters (e.g., link capacity, session dynamics, etc.) that generally challenge resource overprovisioning control. In the second part of this Thesis, we propose a decentralization control mechanism called Advanced Class-based resource OverpRovisioning (ACOR), that aims to achieve better scalability than the ACA approach. ACOR enables multiple CDPs, distributed at network edge, to cooperate and exchange appropriate control data (e.g., trees and bandwidth usage information) such that each CDP is able to maintain a good knowledge of the network topology and the related links resource statistics on real-time basis. From scalability perspective, ACOR cooperation is selective, meaning that control information is exchanged dynamically among only the CDPs which are concerned (correlated). Moreover, the synchronization is carried out through our proposed concept of Virtual Over-Provisioned Resource (VOPR), which is a share of over-reservations of each interface to each tree that uses the interface. Thus, each CDP can process several session requests over a tree without requiring synchronization between the correlated CDPs as long as the VOPR of the tree is not exhausted. Analytical and simulation results demonstrate that aggregate over-reservation control in decentralized scenarios keep low signalling without QoS violations or waste of resources. We also introduced a control signalling protocol called ACOR Protocol (ACOR-P) to support the centralization and decentralization designs in this Thesis. Further, we propose an Extended ACOR (E-ACOR) which aggregates the VOPR of all trees that originate at the same CDP, and more session requests can be processed without synchronization when compared with ACOR. In addition, E-ACOR introduces a mechanism to efficiently track network congestion information to prevent unnecessary synchronization during congestion time when VOPRs would exhaust upon every session request. The performance evaluation through analytical and simulation results proves the superiority of E-ACOR in minimizing overall control signalling overhead while keeping all advantages of ACOR, that is, without incurring QoS violations or waste of resources. The last part of this Thesis includes the Survivable ACOR (SACOR) proposal to support stable operations of the QoS and network control mechanisms in case of failures and recoveries (e.g., of links and nodes). The performance results show flexible survivability characterized by fast convergence time and differentiation of traffic re-routing under efficient resource utilization i.e. without wasting bandwidth. In summary, the QoS and architectural control mechanisms proposed in this Thesis provide efficient and scalable support for network control key sub-systems (e.g., QoS and resource control, traffic engineering, multicasting, etc.), and thus allow for optimizing network overall control performance.
À medida que as Tecnologias de Informação (TIs) se tornaram parte integrante da nossa sociedade, a expectativa dos cidadãos relativamente ao uso desses serviços também demonstrou um aumento, seja no âmbito das atividades profissionais, de lazer, aplicações de segurança crítica ou negócios. Portanto, as limitações dos projetos de rede tradicionais quanto ao fornecimento de serviços inovadores e aplicações avançadas motivaram um consenso quanto à integração de todos os serviços e infra-estruturas de comutação de pacotes, utilizando o IP, de modo a extrair benefícios económicos e um controlo mais flexível nas Redes de Nova Geração (RNG). Entretanto, tendo em vista que a Internet não apresenta capacidade de diferenciação de serviços, e sabendo que cada serviço apresenta as suas necessidades próprias, como por exemplo, a Qualidade de Serviço - QoS, a necessidade de formas mais evoluídas de comunicação tem-se tornado cada vez mais visível, levando a mudanças radicais na arquitectura das redes, que exigem soluções adequadas para a admissão de serviços e controlo de recursos de rede. Sendo assim, este trabalho aborda questões de controlo de QoS e rede com o objetivo de melhorar o desempenho do controlo de recursos total em redes atuais e futuras, através da análise dos serviços de acordo com as suas classes de serviço. Esta Tese encontra-se dividida em três partes. Na primeira parte são propostos dois algoritmos de sobre-reserva, o Class-based bandwidth Over-Reservation (COR) e uma extensão melhorada do COR denominado de Enhanced COR (ECOR). A sobre-reserva significa a reserva de uma largura de banda maior para o serviço em questão do que uma classe de serviço (CoS) necessita e, portanto, a quantidade de sinalização para reserva de recursos é reduzida. COR e ECOR consideram uma definição dinâmica de sobre-reserva de parâmetros para CoSs com base nas condições da rede, com vista à redução da sobrecarga de sinalização em QoS sem que ocorra desperdício de largura de banda. O ECOR, por sua vez, difere do COR por permitir a otimização com minimização de controlo de overhead. Além disso, nesta Tese é proposto também um mecanismo de controlo centralizado chamado Advanced Centralization Architecture (ACA) , usando um único Ponto de Controlo de Decisão (CDP) que mantém uma visão ampla da topologia de rede e de análise dos recursos ocupados em tempo real como base de controlo para a rede global. Nesta Tese são utilizadas árvores multicast como base para o transporte de sessão, não só para fins de comunicação em grupo, mas principalmente para que os pacotes que pertençam a uma sessão que é mapeada numa determinada árvore sigam o seu caminho. Os resultados obtidos nas simulações dos mecanismos mostram uma redução significativa da sobrecarga da sinalização de controlo, sem a violação dos requisitos de QoS ou desperdício de recursos. Além disso, foi proposto um modelo analítico no sentido de avaliar o impacto provocado por diversos parâmetros (como por exemplo, a capacidade da ligação, a dinâmica das sessões, etc), no sobre-provisionamento dos recursos. Na segunda parte desta tese propôe-se um mecanismo para controlo descentralizado de recursos denominado de Advanced Class-based resource OverprRovisioning (ACOR), que permite obter uma melhor escalabilidade do que o obtido pelo ACA. O ACOR permite que os pontos de decisão e controlo da rede, os CDPs, sejam distribuídos na periferia da rede, cooperem entre si, através da troca de dados e controlo adequados (por exemplo, localização das árvores e informações sobre o uso da largura de banda), de tal forma que cada CDP seja capaz de manter um bom conhecimento da topologia da rede, bem como das suas ligações. Do ponto de vista de escalabilidade, a cooperação do ACOR é seletiva, o que significa que as informações de controlo são trocadas de forma dinâmica apenas entre os CDPs analisados. Além disso, a sincronização é feita através do conceito proposto de Recursos Virtuais Sobre-Provisionado (VOPR), que partilha as reservas de cada interface para cada árvore que usa a interface. Assim, cada CDP pode processar pedidos de sessão numa ou mais árvores, sem a necessidade de sincronização entre os CDPs correlacionados, enquanto o VOPR da árvore não estiver esgotado. Os resultados analíticos e de simulação demonstram que o controlo de sobre-reserva é agregado em cenários descentralizados, mantendo a sinalização de QoS baixa sem perda de largura de banda. Também é desenvolvido um protocolo de controlo de sinalização chamado ACOR Protocol (ACOR-P) para suportar as arquitecturas de centralização e descentralização deste trabalho. O ACOR Estendido (E-ACOR) agrega a VOPR de todas as árvores que se originam no mesmo CDP, e mais pedidos de sessão podem ser processados sem a necessidade de sincronização quando comparado com ACOR. Além disso, E-ACOR introduz um mecanismo para controlar as informações àcerca do congestionamento da rede, e impede a sincronização desnecessária durante o tempo de congestionamento quando os VOPRs esgotam consoante cada pedido de sessão. A avaliação de desempenho, através de resultados analíticos e de simulação, mostra a superioridade do E-ACOR em minimizar o controlo geral da carga da sinalização, mantendo todas as vantagens do ACOR, sem apresentar violações de QoS ou desperdício de recursos. A última parte desta Tese inclui a proposta para recuperação a falhas, o Survivability ACOR (SACOR), o qual permite ter QoS estável em caso de falhas de ligações e nós. Os resultados de desempenho analisados mostram uma capacidade flexível de sobrevivência caracterizada por um tempo de convergência rápido e diferenciação de tráfego com uma utilização eficiente dos recursos. Em resumo, os mecanismos de controlo de recursos propostos nesta Tese fornecem um suporte eficiente e escalável para controlo da rede, como também para os seus principais sub-sistemas (por exemplo, QoS, controlo de recursos, engenharia de tráfego, multicast, etc) e, assim, permitir a otimização do desempenho da rede a nível do controlo global.

This dissertation introduces a Dynamical Neural Network (DNN) model based adaptive inverse optimal control design for a class of nonlinear systems. A DNN structure is developed and stabilized based on a control Lyapunov function (CLF). The CLF must satisfy the partial Hamilton Jacobi-Bellman (HJB) equation to solve the cost function in order to prove the optimality. In other words, the control design is derived from the CLF and inversely achieves optimality when the given cost function variables are determined posterior. All the stability of the closed loop system is ensured using the Lyapunov-based analysis. In addition to structure stability, uncertainty/ disturbance presents a problem to a DNN in that it could degrade the system performance. Therefore, the DNN needs a robust control against uncertainty. Sliding mode control (SMC) is added to nominal control design based CLF in order to stabilize and counteract the effects of disturbance from uncertain DNN, also to achieve global asymptotic stability. In the next section, a DNN observer is considered for estimating states of a class of controllable and observable nonlinear systems. A DNN observer-based adaptive inverse optimal control (AIOC) is needed. With weight adaptations, an adaptive technique is introduced in the observer design and its stabilizing control. The AIOC is designed to control a DNN observer and nonlinear system simultaneously while the weight parameters are updated online. This control scheme guarantees the quality of a DNN's state and minimizes the cost function. In addition, a tracking problem is investigated. An inverse optimal adaptive tracking control based on a DNN observer for unknown nonlinear systems is proposed. Within this framework, a time-varying desired trajectory is investigated, which generates a desired trajectory based on the external inputs. The tracking control design forces system states to follow the desired trajectory, while the DNN observer estimates the states and identifies unknown system dynamics. The stability method based on Lyapunov-based analysis is guaranteed a global asymptotic stability. Numerical examples and simulation studies are presented and shown for each section to validate the effectiveness of the proposed methods.

In relation to the increasing interest in implementing smart cities, deployment of widespread wireless sensor networks (WSNs) has become a current hot topic. Among the application’s greatest challenges, there is still progress to be made concerning energy consumption and quality of service. Consequently, this project aims to explore a series of feasible solutions to improve the WSN energy efficiency for data aggregation by the WSN. This by strategically adjusting the position of the receiving base station and the packet rate of the WSN nodes. Additionally, the low-energy adaptive clustering hierarchy (LEACH) protocol is coupled with the WSN state of charge (SoC). For this thesis, a WSN was defined as a two dimensional area which contains sensor nodes and a mobile sink, i.e. a movable base station. Subsequent to the rigorous analyses of the WSN data clustering principles and system-wide dynamics, two different developing strategies, model-based and data-driven designs, were employed to develop two corresponding control approaches, model predictive control and reinforcement learning, on WSN energy management. To test their performance, a simulation environment was thus developed in Python, including the extended LEACH protocol. The amount of data transmitted by an energy unit is adopted as the index to estimate the control performance. The simulation results show that the model based controller was able to aggregate over 22% more bits than only using the LEACH protocol. Whilst the data driven controller had a worse performance than the LEACH network but showed potential for smaller sized WSNs containing a fewer amount of nodes. Nonetheless, the extension of the LEACH protocol did not give rise to obvious improvement on energy efficiency due to a wide range of differing results.
I samband med det ökande intresset för att implementera så kallade smart cities, har användningen av utbredda trådlösa sensor nätverk (WSN) blivit ett intresseområde. Bland applikationens största utmaningar, finns det fortfarande förbättringar med avseende på energiförbrukning och servicekvalité. Därmed så inriktar sig detta projekt på att utforska en mängd möjliga lösningar för att förbättra energieffektiviteten för dataaggregation inom WSN. Detta gjordes genom att strategiskt justera positionen av den mottagande basstationen samt paketfrekvensen för varje nod. Dessutom påbyggdes low-energy adaptive clustering hierarchy (LEACH) protokollet med WSN:ets laddningstillstånd. För detta examensarbete definierades ett WSN som ett två dimensionellt plan som innehåller sensor noder och en mobil basstation, d.v.s. en basstation som går att flytta. Efter rigorös analys av klustringsmetoder samt dynamiken av ett WSN, utvecklades två kontrollmetoder som bygger på olika kontrollstrategier. Dessa var en modelbaserad MPC kontroller och en datadriven reinforcement learning kontroller som implementerades för att förbättra energieffektiviteten i WSN. För att testa prestandan på dom två kontrollmetoderna, utvecklades en simulations platform baserat på Python, tillsamans med påbyggnaden av LEACH protokollet. Mängden data skickat per energienhet användes som index för att approximera kontrollprestandan. Simuleringsresultaten visar att den modellbaserade kontrollern kunde öka antalet skickade datapacket med 22% jämfört med när LEACH protokollet användes. Medans den datadrivna kontrollern hade en sämre prestanda jämfört med när enbart LEACH protokollet användes men den visade potential för WSN med en mindre storlek. Påbyggnaden av LEACH protokollet gav ingen tydlig ökning med avseende på energieffektiviteten p.g.a. en mängd avvikande resultat.

Las pilas de combustible son muy ventajosas debido a su alta eficiencia en la conversión de energía y nula contaminación. En esta tesis se realiza un extenso estudio sobre el control y diseño de sistemas de generación eléctrica basados en pilas de combustible. El núcleo principal de la misma son los sistemas híbridos con pilas de combustible y supercapacitores como elementos almacenadores de energía, orientado a aplicaciones automotrices. La determinación del Grado de Hibridización (i.e. la determinación del tamaño de la pila de combustible y del número de supercapacitores) se realiza mediante una metodología propuesta con el objetivo de satisfacer requisitos de conductibilidad y consumiendo la menor cantidad de hidrógeno posible.

El proceso de diseño comienza con la determinación de la estructura eléctrica de generación del vehículo y utiliza un modelo detallado realizado en ADVISOR, una herramienta para modelado y estudio de sistemas híbridos. Se analiza el flujo de energía a través de los componentes del vehículo cuando el vehículo sigue diferentes ciclos de conducción estándares, mostrando las pérdidas en cada componente que degradan la eficiencia del sistema y limitan la recuperación de energía de frenado. Con respecto a la recuperación de energía, se ha definido y analizado un parámetro que cuantifica la cantidad de energía que realmente es reaprovechada: el ratio frenado/hidrógeno.

Para controlar el flujo de energía entre la pila de combustible, los almacenadores de energía y la carga eléctrica, se proponen tres Estrategias de Gestión de Energía (EMS) para Vehículos Híbridos con Pila de Combustible (FCHVs) basadas en el mapa de eficiencia de la pila y se validan mediante un montaje experimental desarrollado para emular el sistema híbrido. Los resultados de consumo de hidrógeno son comparados con dos referencias: el consumo correspondiente al caso del vehículo sin hibridización y el caso óptimo con el menor consumo para el vehículo propuesto. El consumo óptimo se calcula mediante una metodología propuesta que, a diferencia de otras, evita la discretización de las variables de estado.

Para operar el sistema eficientemente, la pila de combustible es controlada mediante una metodología de control, basada en Control de Matriz Dinámica (DMC). Esta metodología de control utiliza como variables de control el voltaje de compresor y una nueva variable propuesta: la apertura de una válvula proporcional ubicada a la salida del cátodo. Los objetivos de control son controlar el exceso de oxígeno en el cátodo y el voltaje generado por la pila. Se analiza tanto en régimen estacionario como transitorio las ventajas de emplear esta nueva variable de control y se muestran resultados de funcionamiento por simulación del controlador ante perturbaciones en la corriente de carga.

Por otro lado, se aborda el diagnóstico y el control tolerante a fallos del sistema basado en pila de combustible proponiendo una metodología de diagnóstico basada en las sensibilidades relativas de los fallos y se muestra que la estructura de control con las dos variables propuestas tiene buena capacidad de rechazo a fallos en el compresor cuando se controla el exceso de oxígeno en el cátodo.
The use of fuel cell systems based on hydrogen is advantageous because of their high efficiency in the energy conversion and null emissions. In this thesis, an extensive study about the control and design of electrical generation systems based on fuel cells is performed. The main focus is in hybrid systems composed of fuel cells and supercapacitors as energy storage elements, oriented to automotive applications. The determination of the hybridization degree (i.e. the determination of the fuel cell size and the number of supercapacitors) is performed through a proposed methodology with the objective to fulfil the conductibility requirements and to consume the lowest amount of hydrogen.

The process of design starts with the determination of the electrical structure and utilizes a detail model developed using ADVISOR, a MATLAB toolbox for modelling and studying hybrid vehicles. The energy flow between the vehicle components is analyzed when the vehicle is tested with different Standard Driving Cycles, showing how the losses in each component degrade the efficiency of the system and limit the energy recovery from braking.

With regard to the energy recovery, a parameter to quantify the amount of energy that is actually reused is defined and analyzed: the braking/hydrogen ratio.
To control the energy flow between the fuel cell, the energy storage system, and the electrical load in Fuel Cell Hybrid Vehicles (FCHVs), three Energy Management Strategies (EMSs) based on the fuel cell efficiency map are presented and validated through an experimental setup, which is developed to emulate the FCHV. The resulting hydrogen consumptions are compared with two references: the consumption of the pure fuel cell case, a vehicle without hybridization, and the optimal case with the minimum consumption. The optimal consumption for a given vehicle is determined through a methodology proposed that, unlike other previous methodologies, avoids the discretization of the state variables.

To operate the fuel cell system efficiently, the system is controlled through a proposed control technique, which is based on Dynamic Matrix Control (DMC). This control technique utilizes the compressor voltage as control variable and also a new proposed variable: the opening area of a proportional valve at the cathode outlet. The control objectives are the control of the oxygen excess ratio at the cathode and the fuel cell voltage. The advantages of this new control variable are analyzed both in steady state and transient state. Simulation results show and adequate performance of the controller when a series of step changes in the load current is applied.

On the other hand, the diagnosis and fault-tolerant control of the fuel cell-based system is approached. A diagnosis methodology based on the relative fault sensitivity is proposed. The performance of the methodology to detect and isolate a set of proposed failures is analyzed and simulation results in an environment developed to include the set of faults are given. The fault-tolerant control is approached showing that the proposed control structure with two control variables has good capability against faults in the compressor when the oxygen excess ratio in the cathode is controlled.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Ocean Engineering, 2004.
Includes bibliographical references (leaves 126-134).
This thesis presents a parametric and feature-based methodology for the design of solids with local composition control (LCC). A suite of composition design features are conceptualized and implemented. The designer can use them singly or in combination, to specify the composition of complex components. Each material composition design feature relates directly to the geometry of the design, often relying on user interaction to specify critical aspects of the geometry. This approach allows the designer to simultaneously edit geometry and composition by varying parameters until a satisfactory result is attained. The identified LCC features are those based on volume, transition, pattern, and (user-defined) surface features. The material composition functions include functions parametrized with respect to distance or distances to user-defined geometric features; and functions that use Laplace's equation to blend smoothly various boundary conditions including values and gradients of the material composition on the boundaries. The Euclidean digital distance transform and the boundary element method are adapted to the efficient computation of composition functions. Theoretical and experimental complexity, accuracy and convergence analyses are presented. The developed model is a multi-level and graph-based representation, thereby allowing for controls on the model validity and efficiency in model management. The representations underlying the composition design features are analytic in nature and therefore concise. Evaluation for visualization and fabrication is performed only at the resolutions required for these purposes, thereby reducing the computational burden.
by Hongye Liu.
Ph.D.

Bibliography: leaves 136-145.
This thesis is concerned with the application of a method for control system design based on Youla(Q)-Parametrization. The fundamental concepts of the parametrization method have been used by Newton et al, Franklin and Raggazzini [Maciejewski, 1989] as early as 1957. The importance of its implications were not noticed during those years, but Youla and Kucera renewed it in the seventies [Maciejewski, 1989]. For the special case of an open loop stable plant, the implementation can be realized in the Internal Model Control(IMC)-Structure [Morari, 1987]. The IMC-Structure is essentially a open loop design method for closed loop controllers, thereby simplifying the design procedure. A Multivariable controller design method is proposed that unifies the advantages offered by three design approaches/techniques, namely, The Q-Parametrization, The IMC-Structure and The Characteristic Loci Technique. The proposed method is based on controller parametrization. In addition, it retains the engineering insight and simplicity of the IMC-Structure. This is particularly useful in solving complex multivariable problems. The design method was evaluated by its application to the design of a control law for a FLOTATION PROCESS SIMULATOR RIG(FLOTRIG) built by Mr Fisher[Fisher, 1988]. The design of the Multivariable controller was based on a Transfer Function Matrix, G(s), which is a Linear Time Invariant(LTI) model of the FLOTRIG.

Dielectric materials have been applied in modifying the antenna radiation pattern, but it is usually limited to single-beam applications. The goal of this paper is to present a novel methodology to control the antenna radiation pattern based on 3D printing technology. 3D printing enables arbitrary dielectric distribution at different locations. As a result, different radiation patterns can be realized by loading an optimized dielectric material with varied permittivity. In this work, we propose a design of a quarter-wavelength monopole antenna surrounded by a low-profile 3D-printed polymer structure with an optimized dielectric distribution. Unlike the conventional omnidirectional pattern of the monopole antenna, singlebeam and multiple-beam patterns are achieved using genetic algorithm (GA) optimization.

Dielectric materials have been applied in modifying the antenna radiation pattern, but it is usually limited to single-beam applications. The goal of this paper is to present a novel methodology to control the antenna radiation pattern based on 3D printing technology. 3D printing enables arbitrary dielectric distribution at different locations. As a result, different radiation patterns can be realized by loading an optimized dielectric material with varied permittivity. In this work, we propose a design of a quarter-wavelength monopole antenna surrounded by a low-profile 3D-printed polymer structure with an optimized dielectric distribution. Unlike the conventional omnidirectional pattern of the monopole antenna, singlebeam and multiple-beam patterns are achieved using genetic algorithm (GA) optimization.

The current year, 2021, started with the landing of the Perseverance mission and the flight of the first drone on Mars, marking an important event in the history of space exploration. The exploration of new environments would be easier and characterised by the absence of various obstacles if implementing a larger use of drones. This thesis project represents a first attempt to design a space UAV based on thrusters, in order to permit its use also in vacuum: the purpose is to demon- strate the possibility to use and control this new space technology after selecting the adequate components. Lists of environments and thrusters are mentioned to give a general idea of the possibilities; afterwards, a trade-off between all these choices is done, picking HPGP thrusters and Interamnia 704 as exploration site. The design included offers a great glimpse about all the necessary subsystems and focuses on propulsion and GNC subsystem. The second part of the document aims the attention on the dynamics of the pro- posed platform, developing a mathematical model and the state space form. These information are used for the guidance and control algorithms: Explicit Guidance and Non-Linear Dynamic Inversion control. The results found are then shown and verified: demonstrating the feasibility of the drone and its autonomous control for exploration and mapping purposes.

An integrated computational approach to Ship Concept Design using optimization techniques and a knowledge base to control the optimization process has been developed. The system automates both synthesis and analysis; analysis by the repeated sequential use of Design Theory Modules and synthesis through the optimization process, which compromises conflicting requirements, subject to constraints. The intention of this work has been to find a better approach to automated design synthesis and at the same time employ detailed analytical tools such as a three-dimensional hull-form definition and engineering analysis modules. Optimization techniques and a knowledge base are combined to achieve the desired capabilities, taking advantage of the benefits optimization can bring using goal oriented methods and exploratory searches, alongside a knowledge base that controls the synthesis process rather than the design. A function mapping strategy has been developed to provide a multiple-parametric view of regions of the optimization objective function and constraints. A discussion is included on the role of further applications of expert systems to design systems in both synthesis and analysis and their possible interference with creativity and innovation. Two design examples are provided, one showing the application of the system using optimization and the other adding the use of the knowledge base. The results are compared and discussed.

This thesis is concerned with the applicability of model reference adaptive control to the control of robot manipulators under a wide range of configuration and payload changes, and a comparison of the performance of this technique with that of the non-adaptive schemes. The dynamic equations of robot manipulators are highly nonlinear and are difficult to determine precisely. For these reasons there is an interest in applying adaptive control techniques to robot manipulators. In this work, the detailed performance of three adaptive controllers are studied and compared with that of a non-adaptive controller, namely, the computed torque control scheme. Computer simulation results show that the use of adaptive control improves the performance of the manipulator despite changes in the payload or in the manipulator configuration. Making use of these results, a rule-based controller is developed by dividing a given manipulation task into portions where a particular adaptive control scheme, based on a specific linearized subsystem model, performs best. This strategy of selecting the proper controller during each portion of the overall task yields a performance having the least deviation from the desired trajectory during the entire length of the task.

The main objectives were: (1) to develop tools to aid in the design of enclosed agro-ecosystems, and (2) to use these tools to develop a prototype simulation-based control system. Three tools were developed: (1) a conceptual framework, (2) a (simulated) greenhouse system and (3) a simulation approach within OS/2.
Part of the conceptual framework was dedicated to "conscious control", defined as a form of control practised by an entity that uses models of itself in its decision-making processes. The greenhouse system was composed of six modules (a simulation manager, a weather generator, a greenhouse model, a crop model, a Pavlovian controller and a cognitive controller), which were implemented under OS/2 as separate processes.
The greenhouse system was used to develop a prototype simulation-based controller. Primarily, the role of the controller was to determine temperature setpoints that would minimize the heating load. The simulation model used by the controller was an artificial neural network. The controller adapted temperature setpoints to anticipated meteorological conditions and reduced greenhouse energy consumption, in comparison with a more traditional controller.
Generally, the results showed the feasibility and illustrated some of the advantages of using simulation-based control. The research resulted in the definition of elements that will allow the creation of a methodological framework for the design of simulation-based control and, eventually, a theory of conscious control.

Negli ultimi anni, Kubernetes è emerso come l’orchestratore di applicazioni a containers dominante. Il suo design è basato su un’API che permette di descrivere in modo dichiarativo lo stato desiderato delle applicazioni e su un piano di controllo che lavora per far convergere lo stato effettivo delle applicazioni verso lo stato desiderato, ottenendo fault-­tolerance, self-­healing ed elevata scalabilità. Questo design pattern si è dimostrato estremamente efficace per la gestione dei container, ma è abbastanza generale da poter essere usato per orchestrare con successo qualsiasi tipo di risorsa virtuale che viene tradizionalmente offerta mediante il paradigma del cloud IaaS. Abbiamo testato questa idea estendendo Kubernetes per fargli gestire, oltre alle usuali applicazioni a containers, delle reti virtuali. Così facendo abbiamo di fatto realizzato il prototipo di un piano di controllo di una Software­Defined Network. Nel fare ciò sono emersi sia punti di forza che debolezze del design pattern di Kubernetes e delle librerie open source che lo supportano. Per verificare che il sistema ottenuto abbia una scalabilità adeguata a quella necessaria nei moderni cloud data centers, abbiamo condotto uno studio di performance.

The current congestion control mechanisms for the Internet date back to the early 1980’s and were primarily designed to stop congestion collapse with the typical traffic of that era. In recent years the amount of traffic generated by real-time multimedia applications has substantially increased, and the existing congestion control often does not opt to those types of applications. By this reason, the Internet can be fall into a uncontrolled system such that the overall throughput oscillates too much by a single flow which in turn can lead a poor application performance. Apart from the network level concerns, those types of applications greatly care of end-to-end delay and smoother throughput in which the conventional congestion control schemes do not suit. In this research, we will investigate improving the state of congestion control for real-time and interactive multimedia applications. The focus of this work is to provide fairness among applications using different types of congestion control mechanisms to get a better link utilization, and to achieve smoother and predictable throughput with suitable end-to-end packet delay.

The development of a microprocessor based digital flight control system for a particular R.P.V. is described. The tasks required of this system are defined, and thereafter, the hardware circuits and the software structure necessary to implement a prototype are presented. The autopilot control laws are inferred from z-plane root loci, and then confirmed using digital simulations of the de-coupled roll and pitch attitude loops. The problems of the finite wordlength implementation of the control laws are discussed, and then both hybrid simulation and actual flight results are used to prove the performance of the prototype. To exploit the adaptive capabilities of a software based system, a sliding mode variable structure control law is developed for the roll attitude loop. Digital simulations are used to show that significant improvements in sensitivity reduction can be achieved under some conditions. These improvements are lost if a realistic servo-actuator model is employed. Another objective, namely the reduction of the disturbance error induced by trim imbalance, is maintained provided a reduced order switching function is used.

Iterative learning control has been developed for processes or systems that complete the same finite duration task over and over again. The mode of operation is that after each execution is complete the system resets to the starting location, the next execution is completed and so on. Each execution is known as a trial and its duration is termed the trial length. Once each trial is complete the information generated is available for use in computing the control input for next trial. This thesis uses the repetitive process setting to develop new results on the design of higher-order ILC control laws. The basic idea of higher-order ILC is to use information from a finite number of previous trials, as opposed to just the previous trial, to update the control input to be applied on next trial, with the basic objective of improving the error convergence performance. The first set of new results in this thesis develops theory that shows how this improvement can be achieved together with a measure of the improvement available over a non-higher order law. The repetitive process setting for analysis is known to require attenuation of the frequency content of the previous trial error from trial-to-trial over the complete spectrum. However, in many cases performance specifications will only be required over finite frequency ranges. Hence the possibility that the performance specifications could be too stringent. The second set of new results in this thesis develop design algorithms that allow different frequency specifications over finite frequency ranges. As in other areas, model uncertainties arise in applications. This motivates the development of a robust control theory and associated design algorithms. These constitute the third set of new results. Unlike alternatives, the repetitive process setting avoids the appearance of product terms between matrices of the nominal system dynamics statespace model and those used to describe the uncertainty set. Finally, detailed simulation results support the new designs, based on one axis of a gantry robot executing a pick and place operation to which iterative learning control is especially suited.

碩士
逢甲大學
化學工程學所
91
Abstract In the past decade, many research reports have proven that the adaptive single neuron controller（SNC）has a great capability in handling the chemical process control problems, mainly due to the learning ability and its simple but nonlinear structure. However, the common drawback is the lack of a systematic way in selecting initial controller parameters, which generally inhibits the ease of practical implementation. Therefore, this dissertation first aims at giving a systematic methodology for controller start-up process. A simple rule, which relates the controller’s initial parameters by a performance index parameter, has been derived based on a first-order process model. Having solved the SNC initialization problem, we further propose a model-based control system for time-delay processes. The scheme incorporates a Smith predictor and a feedforward controller with the SNC. For dealing with plant/model mismatch problem, a parameter tuning rule is presented for direct adaptive control. The extension to nonlinear process control is also addressed in this dissertation. Extensive simulation results show that the proposed initialization method and proposed control scheme are effective and promising for chemical process control, which provides robust and high control system performance.

碩士
國立臺灣科技大學
機械工程系
87
Because of the traditional design methods could not solve the problems of the uncertainty of systems and the advantage of neural network is that the mathematical model is not needed，neural network is chosen to realize the controller in many research fields recently. Many research results are distributed over many references. There are several approaches to construct a neural network. So it''s rare for a book in which the theoretical structure of neural networks embedded in control systems is discussed and analyzed. This thesis tries to conclude several neural network control structures which are often used in literature. Then the steps of neural network based controller realization are listed and are proved with simulations. A novel identifier realization strategy is proposed so that the system Jacobian can be calculated easily. At last, this thesis applies the parallel neuro-control scheme on the simulation of a two-link robot which gradually achived the requirement with repeatedly learning under the situation without knowing the mathematical model of the robot and the environment in advance.

碩士
國立暨南國際大學
電機工程學系
105
In today's society, people rely on a large number of robots to complete most of the things, and now the aging population of the community is that we have been faced with the problem, this time in the service-oriented robot is very important. The current handling robot on the market is a very good example, but in view of the speed of control when moving goods this piece is a very important part of the current to see there are still many robots can not be 100% speed feedback control. This thesis presents a solution to this problem, using the Verilog Hardware Description Language (Verilog HDL), with the encoder to achieve speed feedback control, we use the three sets of PWM speed. When the machine can be free to switch the wheel speed, and then deliver the value of the encoder to our laboratory CPU.

碩士
淡江大學
電機工程學系碩士在職專班
99
A control platform design by using the Pineview processor is proposed in this thesis. The implemented control platform has multi-functional features of a small size, light weight, high performance and easy to support software development. Furthermore, the software system is easy to support the system development. It can meet the requirement of small-size humanoid robot in the hardware/software system design. The volume and weight of the implemented hardware platform are 100×72×31 mm3 and 100 gs, respectively. In the system structure design, Pineview processor, which is developed by Intel for next generation notebook, is used to be the control center of this platform. In the circuit board realization, the FR-4 material and SMT process are applied. In the input/output interface design, the Pine Trail development platform is used to integrate many interfaces design, such as USB, Gigabit Ethernet, HD Audio, Wi-Fi, GPIO port, VGA, SPI, I2C, and RS232/485, etc. Let the implemented platform is a pluralistic control interface and the robot can use various kinds of sensors and equipments. In the support of the software system, many items of software systems can be used in the implemented control platform such as Windows XP, Windows 7, Windows CE, and Linux, etc, so that this platform can save time in the system design. In the real verification of the implemented control platform, it has been built on a small-size humanoid robot to illustrate its multiple functions.

碩士
國立高雄應用科技大學
電機工程系碩士班
95
This thesis deals with observer-based H∞ control problem for T-S fuzzy systems. By using Lyapunov stability analysis and LMI techniques. The conditions for existence of H∞ controllers are derived and proved to be more relaxed than the existing ones. When the observer is allowed to contain the system’s disturbance. The existing result can be shown to be a special case of ours. When the observer does not include the system’s disturbance, a two-step approach is employed to solve the derived nonlinear inequalities for finding the controllers and observes.

碩士
國立雲林科技大學
電子與資訊工程研究所
94
The application of Internet has become not only having education value but also having business value such as multimedia transmission, due to the emergence and spring up of Internet and ADSL etc. These reasons induce that all of application will be integrated in IP-based networks. Based on the platform of IP-network, the communication product which has the ability to carry data, voice, control, and video information, will dominate the future markets. The major problem in the automatic industry control system is that how to design a control platform which can support the control conditions of long distance, wide range, and high resolution. Up to now, the most of control platform are focus on the interface of RS-232 or RS-485 which also have the limitation of transmission speed, control range, and wire problem. In this thesis, based on the client/server model we target on the design and implementation a control platform which can be applied to the large coverage control environment. We use the control platform to the light control system. The server side is realized by the personal computer. According to the music play the server sends different control commands to the client module via Ethernet interface. In the client side, based on the 8-bit 8051 micro controller, we integrate the Ethernet interface, communication protocols, and I/O control for light to realize an embedded network control platform which follows the server command to control the on/off of lights. In this thesis, we develop a control platform which has the properties of simple, low cost, large coverage range, and high transmission speed. The control platform can applied to the automatic industry control environment.

碩士
中原大學
電機工程研究所
97
The purpose of this thesis is to develop the intelligent motion control system based on the fuzzy neural network (FNN), and to integrate it with adaptive control, total sliding mode control (TSMC) and robust control technologies for motion control systems. According to Lyapunov synthesis approach, the adaptive tuning laws of FNN can be derived and the system stability can be guaranteed. This thesis introduces the concepts of sliding mode control (SMC), TSMC and FNN first. Then, the design procedures of SMC, TSMC and adaptive TSMC (ATSMC) are developed for the nonlinear motion control systems; that include a ship motion control system and a wing rock motion control system. However, the undesired control chattering also existed in the above control methods. To resolve the problem, this thesis proposes the TSMC-based intelligent motion control system for the same motion control systems. In this design, the adaptive FNN controller acts as the main tracking controller, which is designed via an FNN to mimic an ideal TSMC law and the adaptive robust controller is developed to attenuate the approximation error between the FNN and the ideal TSMC. Finally, comparisons of a SMC, a TSMC, an ATSMC and the proposed TSMC-based intelligent control method for motion control systems are made. The simulation results demonstrate that the proposed FNN and TSMC-based intelligent motion control scheme with PI-type adaptive laws can achieve satisfactory control performance more accurately than other control methods without control charactering.

碩士
明新科技大學
電機工程研究所
95
The main goal of this research is to design the close loop of the control system of permanent magnet synchronous motor, including its speed and current loop of the control circuit and the circuit of the driver with digital circuits. To carry out the controlling rules more rapidly, the speed of the loop is controlled on the basis of PC-Based ways. Besides, the researcher completed the current loop and the circuit of a PWM with the software of FPGA in order for the realization of the IC circuit of driver in the future. The SVPWM technology was chosen in this study because of lower harmonic distortion, lower switching loss and higher voltage utility compared with SPWM technology. However, SVPWM technology is not easy to be realized with the hardware logical circuit. Here, the researcher realized the fully digitalized SVPWM control circuits by programming FPGA device in VHDL since the FPGA devices have the characteristics of programmable circuits and logical operation. Then, this FPGA chip is used to control the Intelligent Power Module (IPM) which constructs the power stage circuit of whole system. The whole circuit except the power stage is realized in an FPGA chip. It can simplify the modification of circuits and reduces the Int.erference of noise. In order to combine the theories with practices and to analyze the state behavior of the circuit in the system, the researcher simulated the design circuit in advance by using Matlab/Simulink. Implements the above functions have simulated by Matlab/Simulink in VHDL and copies into the FPGA chip for making the real software circuit. Also, we construct a real-time PC-based control system for PMSM system with the functions of Matlab-RTWT toolbox. In this way, it can modify and verify the control rules rapidly.

碩士
明新科技大學
電機工程研究所
94
Rotary inverted pendulum is a typical nonlinear unstable system. In its construction, it can be divided into the rotating arm and the inverted pendulum. The rotating arm is rotating on the horizontal plane, while the inverted pendulum is swing to the vertex. This system control law contains two stages, the first is swing up control which drives system unstable, and the next is standing control which gives system asymptotically stable. The main research of this thesis is to design an unstable swing up controller by Cetaev’s instability theorem and a stable standing controller by LQR (Linear Quadratic Regulator) method for PC-Based control. Using the MCS-6A data acquisition card and shaft encoders, the position messages of rotating arm and inverted pendulum can feedback to PC to correct the controller outputs which use to modulate the PWM (Pulse Width Modulation) messages and command rotary inverted pendulum system. By the Matlab-RTWT (Real-Time Windows Target) Toolbox, we will develop special programs in C Language to fit in with S-Function of Matlab/Simulink for MCS-6A data acquisition card. Integrating with the hard ware plant, the PC-Based real-time control system will be gotten. Therefore, the trajectories of state of inverted pendulum system can be monitored immediately on PC.

碩士
國立臺灣科技大學
電機工程系
96
The motivation of this thesis is to design a robot control hardware platform by using the Field Programmable Gate Array chip and the Verilog hardware description language to realize motion control interface circuits, motor position closed loop PID control as well as RS232 communication module. Hierarchical structure and modulization method is adapted to simplify the circuit design and easy to verification. Using this robot hardware platform, we realize a wheeled robot system which is consist of by ten servo motors as well as two DC motors, and design a scenario for the robot making a succession of hand guidance traffic control gestures.