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Structure-Inspired Disturbance Observer Design and Disturbance Observer-Based Control/estimationChen, Ying-Chun 15 August 2023 (has links)
This dissertation consists of two topics: (1) structure-inspired disturbance observer design and (2) disturbance observer-based control/estimation. The disturbance is defined as the discrepancy between a model and the system the model represents. A disturbance observer is an algorithm that generates an estimate of the disturbance. The first topic illustrates a disturbance observer that provides a big class of nonlinear systems with a large basin of attraction, even ensuring global convergence. Such robustness is achieved by leveraging particular system nonlinearities in the observer design. The second topic discusses the usage of disturbance estimates to counteract or capture the effects of disturbances to recover the nominal controller/estimator performance. The main research results are theorems concerning stability analysis of the disturbance observer and the disturbance observer-based systems, whose practical aspects are supported by three application examples---a fixed-wing aircraft, an underwater vehicle, and a Furuta pendulum. / Doctor of Philosophy / This dissertation consists of two topics: (1) structure-inspired disturbance observer design and (2) disturbance observer-based control/estimation. Disturbances are the unknown signals entering the system; an external force, for example, such as the additional lift force due to turbulence surrounding an aircraft is a disturbance. A disturbance observer is an algorithm that estimates the mathematical value of disturbances. The first topic illustrates a disturbance observer whose convergence is guaranteed regardless of the initial condition. Such robustness is achieved by leveraging the system's special properties in the observer design. The second topic discusses the usage of disturbance observers to recover the nominal controller/estimator performance. Control is a study of how make systems behave ideally by properly designing the inputs, while estimation is about how to infer quantities that cannot be directly measured using the measurements that really are available; the solutions are correspondingly called controller and estimator. Disturbance estimates can be exploited by existing controllers and estimators as extra information to counteract or capture the effects of disturbances. The main research results are theorems about the conditions under which these algorithms perform as desired. Practical aspects are supported by three application examples---a fixed-wing aircraft, an underwater vehicle, and a Furuta pendulum.
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Pressure-based Impedance Control of a Pneumatic ActuatorMohorcic, John Francis 04 June 2020 (has links)
No description available.
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Road Surface Condition Detection and Identification and Vehicle Anti-Skid ControlYe, Maosheng January 2008 (has links)
No description available.
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Conciliação, mediação e arbitragem no Brasil neoliberal: as associações patronais e suas instituições mediadoras (1994-2012)Lance, Kleyne Paula Castro 22 March 2014 (has links)
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Previous issue date: 2014-03-22 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / In this work, our aim is to analysis the inter-relation with the institute/organs of mediation and arbitration founded by patronal institutions, showing up the movement that those settle in their midst, as well as, with the public sector. For both, we problematized the politics of reconciliation in the implementation process of Labor Legislation and then, the emergence of laws that have been implemented from this politics in the Brazilian legal scenario. In agreement, we find an infinite of private institutions which have struggled to regulate the Extra-judicial Methods of Dispute Settlement (MESCs) from the spread of Alternative Dispute of Resolution. So, this study narrowed its analysis with the mediation institutions, organs that are directly linked with a fraction of the industrial sector, therefore from the movement of these private apparatus of hegemony was constituted shape and contour to the Extended State from the their activities. Then, we have a hand in defense alternative forms of conflict resolution in court or privately and the other hand the traditional form of conflict resolution . Ultimately, two major projects were identified that are in dispute and that alternative forms have been gaining more space, as well as, they have been disputing this space in civil society, by role of employers and political society, by shareholder of the memberships and /or organic intellectuals / Neste trabalho temos por objetivo analisar a inter-relação de institutos/órgãos de mediação e arbitragem fundados por instituições patronais, evidenciando o movimento que estes estabelecem entre si, bem como, com o setor público. Para tanto, problematizamos a política de conciliação no processo de implementação da Legislação Trabalhista, e posteriormente, o surgimento de Leis que foram implementadas a partir dessa política no cenário jurídico brasileiro. Neste sentido, encontramos uma infinidade de instituições privadas que têm se esforçado em regulamentar os Métodos Extrajudiciais de Solução de Controvérsias (MESCs) a partir da disseminação das Formas alternativas de solução de conflito. Desta forma, este estudo delimitou sua análise às instituições de mediação que são órgãos vinculados diretamente com o uma fração do setor industrial, assim, a partir do movimento desses aparelhos privados de hegemonia , foi-se constituindo forma e contorno ao Estado ampliado a partir de suas atividades. Assim, temos de um lado, a defesa das formas alternativas de resolução de conflito em âmbito extrajudicial ou privado, e de outro, a forma tradicional de resolução de conflito. Enfim, identificamos dois grandes projetos que estão em disputa e que, as formas alternativas vem ganhando mais espaço, bem como, vem disputando este espaço na sociedade civil, via atuação das entidades patronais, e, na sociedade política, via atuação de seus quadros e/ou intelectuais orgânicos
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Disturbance Rejection Control for The Green Bank TelescopeRanka, Trupti 01 June 2016 (has links)
No description available.
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Design and Control of A Ropeless Elevator with Linear Switched Reluctance Motor Drive Actuation SystemsLim, Hong Sun 03 May 2007 (has links)
Linear switched reluctance motor (LSRM) drives are investigated and proved as an alternative actuator for vertical linear transportation applications such as a linear elevator. A one-tenth scaled prototype elevator focused on a home elevator with LSRMs is designed and extensive experimental correlation is presented for the first time.
The proposed LSRM has twin stators and a set of translator poles without back-iron. The translators are placed between the two stators. The design procedures and features of the LSRM and the prototype elevator are described. The designed LSRM is validated through a finite element analysis (FEA) and experimental measurements. Furthermore, a control strategy for the prototype elevator is introduced consisting of four control loops, viz., current, force, velocity, and position feedback control loops. For force control, a novel force distribution function (FDF) is proposed and compared with conventional FDFs. A trapezoidal velocity profile is introduced to control vertical travel position smoothly during the elevator's ascent, descent, and halt operations. Conventional proportional plus integral (PI) controller is used for the current and velocity control loops and their designs are described. The proposed control strategy is dynamically simulated and experimentally correlated. Analytical and experimental results of this research prove that LSRMs are one of the strong candidates for ropeless linear elevator applications.
However, the proposed FDF is assuming that the feedback current signals are ideal currents indicating actual phase currents without any measurement disturbances mainly arising from sensor noise, DC-link voltage ripple, measurement offset, and variations in the plant model. Meanwhile, real control systems in industry have measurement disturbance problems. Phase current corrupted by measurement disturbances increases torque or force ripple, acoustic noise and EMI. Therefore, this dissertation also presents a novel current control method to suppress measurement disturbances without extra hardware.
The controller is based on an extended state observer (ESO) and a nonlinear P controller (NLP). The proposed method does not require an accurate mathematical model of system and can be implemented on a low-cost DSP controller. The proposed ESO is exploited to estimate the measurement disturbances on measured phase currents, and the proposed NLP compensates for the measurement disturbances estimated by the ESO. The performance of the proposed current control is validated through extensive dynamic simulations and experiments. Moreover, this rejection of measurement disturbances results in a reduction of force ripple and acoustic noise. Due to superior and robust current control performance, it is believed that the proposed method can be successfully applied into other motor drive systems to suppress measurement disturbances with the same promising results without extra hardware. / Ph. D.
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CURSOS DE DIREITO NO BRASIL: EMBATES EM TORNO DA EXPANSÃO E DO CONTROLE DO EXERCÍCIO PROFISSIONAL (1995-2002) / Law Courses in Brazil: collisions around the expansion and control of the professional performance (1995-2002)CRUVINEL, érika Bernardes Palazzo Ribeiro 09 December 2008 (has links)
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Previous issue date: 2008-12-09 / The target of this present investigation consists of to analyze the expansion process of the
Brazilian college, especially Law Courses, for the period of 1995-2002. In a strict sense, it
studies the established collisions by the civil society and the State around the expansion of
Law Courses and the control of the professional performance. To reach these targets, the
proposals for Law education were analyzed, done by the main political subjects involved with
this discussion: The Brazilian Lawyers Order Ordem dos Advogados do Brasil (OAB) , The
Private Universities Association Associação das Universidades Privadas (Anup) , and The
Maintainers of College Education Brazilian Association Associação Brasileira das
Mantenedoras de Ensino Superior (Abmes) . A bibliography research was realized with the
objective of grasping the meaning of the entities proposals and knowing the reform of the
State s proposal, and the educational legislation of FHC Government. Available information
from INEP/MEP subsidized the characterization of the college education expansion and of the
law courses during this studied period of time. The research refers to the large concept of state
by Gramsci (2000), which contributed to the comprehension of the relation between the State
and the civil society of the end of 1990 s decade and the beginning of the 21st century. In this
context, Law Courses presented a accelerated expansion, with concentration of supplies in
private college institutions and non-universities courses. This moment was marked by a strong
discussion about the Law courses expansion, their quality and the control of the professional
performance executed by OAB. / O objetivo da presente investigação consiste em analisar o processo de expansão do ensino
superior no Brasil, sobretudo dos cursos de Direito, no período 1995-2002. Estuda os embates
estabelecidos na sociedade civil e no Estado, em sentido estrito, em torno da expansão dos
cursos de Direito e do controle do exercício profissional. Para alcançar esses objetivos, foram
analisadas as propostas para o ensino jurídico, dos principais sujeitos políticos envolvidos
nesse debate: Ordem dos Advogados do Brasil (OAB), Associação das Universidades
Privadas (Anup) e Associação Brasileira das Mantenedoras do Ensino Superior (Abmes). Foi
realizada pesquisa bibliográfica e documental com o objetivo de apreender as proposições das
entidades e conhecer a proposta de reforma do Estado e a legislação educacional do Governo
FHC. Dados disponibilizados pelo INEP/MEC subsidiaram a caracterização da expansão do
ensino superior e dos cursos de Direito no período estudado. A pesquisa teve como referencial
o conceito ampliado de Estado de Gramsci (2000), que contribuiu para a apreensão da relação
entre Estado e sociedade civil no final dos anos 1990 e início do século XXI. Nesse contexto,
os cursos de Direito apresentaram uma expansão acelerada, com oferta concentrada em IES
privadas e não-universitárias. O momento foi marcado por intenso debate acerca da expansão
dos cursos de Direito, de sua qualidade e do controle do exercício profissional exercido pela
OAB.
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Robust control for manipulation inside a scanning electron microscope / Commande robuste pour la manipulation in situ microscope électronique à balayage -Robust control for manipulation inside a scanning electron microscopeGaudenzi de faria, Marcelo 17 February 2016 (has links)
Cette thèse étudie le problème de nano-positionnement à l'intérieur d'un microscope électronique à balayage (MEB). Pour obtenir des informations de position avec rapidité et précision, une installation dédiée composée d’un vibromètre placé à l'intérieur du MEB a été mise en œuvre. Cette approche diffère de méthodes basées sur le traitement d'images, car elle permet de saisir des données en temps réel sur le comportement dynamique des structures étudiées. Dans une première étude, les perturbations mécaniques agissant à l'intérieur de la chambre à vide du microscope ont été caractérisées et leurs sources ont été identifiées. Cela a démontré comment les vibrations mécaniques externes et les bruits acoustiques peuvent influer largement sur les composants à l'intérieur du MEB par couplage mécanique, limitant ainsi la précision des manipulateurs. Dans un deuxième temps, une micro-pince du commerce a été étudiée. Une différence entre ses comportements dans l'air et dans le vide a été mise en évidence, ce qui a permis d'obtenir deux modèles dynamiques pour cet organe terminal, un pour chaque environnement. Deux lois de commande ont été proposées (commande H-infini et commande basée sur un observateur d'état étendu), afin d'obtenir en temps réel un positionnement précis dans le vide, et d'atténuer les effets des perturbations mécaniques externes. Les résultats ont été validés en simulation et expérimentalement. / This work studies the nano-positioning problem inside the scanning electron microscope (SEM). To acquire fast and accurate positional information, a dedicated setup was implemented consisting of a vibrometer placed inside the SEM. This approach differs from methods based on image processing, as it allows to capture real-time data on the dynamic behavior of structures. In a first study, the mechanical disturbances acting inside the microscope’s vacuum chamber were characterized and its sources were identified. This demonstrated how external mechanical vibrations and acoustic noises can largely influence the components inside the SEM through mechanical coupling, limiting the effective positioning precision of manipulators. Next, a commercial micro-gripper was studied, both in air and in vacuum, and the differences between its response were highlighted. This allowed to obtain two dynamic models for this end-effector, one for each environment. Two control laws were proposed (H-infinity control and Extended State Observer based control) for the system, to obtain a real-time, precise positioning in the vacuum environment and to attenuate the effects of the external mechanical disturbances. Results were demonstrated through simulation and experimental validation.
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