Dissertations / Theses on the topic 'Recursive control'
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1
Barbosa, Filipe Marques. "Robust recursive path-following control for autonomous heavy-duty vehicles." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/18/18153/tde-14032019-082753/.
Abstract:
Path following and lateral stability are crucial issues for autonomous vehicles. Moreover, these problems increase in complexity when handling heavy-duty vehicles due to their poor manoeuvrability, large sizes and mass variation. In addition, uncertainties on mass may have the potential to significantly decrease the performance of the system, even to the point of destabilising it. These parametric variations must be taken into account during the design of the controller. However, robust control techniques usually require offline adjustment of auxiliary tuning parameters, which is not practical and leads to sub-optimal operation. Hence, this work presents an approach to path-following and lateral control for autonomous heavy-duty vehicles subject to parametric uncertainties by using a robust recursive regulator. The main advantage of the proposed controller is that it does not depend on the offline adjustment of tuning parameters. Parametric uncertainties were assumed to be on the payload, and an H∞ controller was used for performance comparison in simulations. The performance of both controllers is evaluated in a double lane-change manoeuvre. Simulation results showed that the proposed method had better performance in terms of robustness, lateral stability, driving smoothness and safety, which demonstrates that it is a very promising control technique for practical applications. Ultimately, experiment tests in a rigid heavy-duty truck validate what was found in simulation results.O seguimento de caminho e a estabilidade lateral são questões cruciais para veículos autônomos. Além disso, devido à baixa capacidade de manobra, tamanho e grande variação de massa, estes problemas se tornam mais complexos quando se trata de veículos pesados. Adicionalmente, as incertezas na massa têm o potencial de diminuir significativamente o desempenho do sistema, chegando ao ponto de desestabilizá-lo, assim, essas variações paramétricas devem ser consideradas durante o projeto do controlador. No entanto, as técnicas de controle robusto geralmente exigem o ajuste off-line de parâmetros auxiliares do controlador, o que não é prático e lava a uma operação sub-ótima. Assim, este trabalho apresenta uma abordagem de controle de seguimento de caminho e controle lateral para veículos pesados autônomos sujeitos a incertezas paramétricas usando um regulador robusto recursivo. A principal vantagem deste controlador é que ele não depende do ajuste off-line de parâmetros. Assumiu-se que as incertezas paramétricas estavam na carga do veículo, e um controlador H∞ foi usado para comparar o desempenho em simulação. O desempenho de ambos os controladores é avaliado em uma manobra de mudança de faixa. Os resultados de simulação mostraram que o método proposto apresentou melhor desempenho em termos de robustez, estabilidade lateral, suavidade na condução e segurança, o que o demonstra como uma técnica de controle bastante promissora para aplicações práticas. Por fim, testes experimentais em um caminhão rígido reforçam os resultados obtidos em simulação.
2
Oliveira, Tiago Miguel Brites. "Recursive neuro fuzzy techniques for online identification and control." Master's thesis, Faculdade de Ciências e Tecnologia, 2013. http://hdl.handle.net/10362/10552.
Abstract:
Dissertação para obtenção do Grau de Mestre em
Engenharia Electrotécnica e de ComputadoresThe main goal of this thesis will be focused on developing an adaptative closed loop control solution, using fuzzy methodologies. A positive theoretical and experimental contribution, regarding modelling and control of fuzzy and neuro fuzzy systems, is expected to be achieved. Proposed non-linear identification solution will use for modelling and control, a recurrent neuro fuzzy architecture. Regarding model solution, a state space approach will be considered during fuzzy consequent local models design. Developed controller will be based on model parameters, being expected not only a stable closed loop solution, but also a static error with convergence towards zero. Model and controller fuzzy subspaces, will be partitioned throughout process dynamical universe, allowing fuzzy local models and controllers commutation and aggregation. With the aim of capturing process under control dynamics using a real time approach, the use of recursive optimization techniques are to be adopted. Such methods will be applied during parameter and state estimation, using a dual decoupled Kalman filter extended with unscented transformation. Two distinct processes one single-input (SISO) other multi-input (MIMO), will be used during experimentation. It is expected from experiments, a practical validation of proposed solution capabilities for control and identification. Presented work will not be completed, without first presenting a global analysis of adopted concepts and methods, describing new perspectives for future investigations.
3
Brus, Linda. "Recursive black-box identification of nonlinear state-space ODE models." Licentiate thesis, Uppsala : Department of Information Technology, Uppsala University, 2006. http://www.it.uu.se/research/publications/lic/2006-001/.
4
Sarkar, Subhasis. "Recursive formulations of multibody systems in open loop configuration." Diss., Georgia Institute of Technology, 1992. http://hdl.handle.net/1853/12414.
5
ABDALLA, TALAL ALMUTAZ ALMANSI. "Recursive Algorithms for Set-Membership Estimation." Doctoral thesis, Politecnico di Torino, 2022. https://hdl.handle.net/11583/2972788.
6
Baker, Rob. "Some possibilities for the use of a recursive predictor in self-tuning algorithms." Thesis, University of Newcastle Upon Tyne, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.316054.
7
Natarajan, Bharath. "Area Access Control Systems: Zone Management And Personnel Tracking." [Tampa, Fla.] : University of South Florida, 2005. http://purl.fcla.edu/fcla/etd/SFE0001247.
8
Boonnithivorakul, Nattapong. "Recursive on-line strategy for optimal control of a class of nonlinear systems /." Available to subscribers only, 2006. http://proquest.umi.com/pqdweb?did=1136091921&sid=7&Fmt=2&clientId=1509&RQT=309&VName=PQD.
9
Burridge, Michael J. "Nonlinear robust control of a series dc motor utilizing the recursive design approach." Master's thesis, University of Central Florida, 1995. http://digital.library.ucf.edu/cdm/ref/collection/RTD/id/24126.
Abstract:
University of Central Florida College of Engineering ThesisIn this thesis, the investigation of asymptotic stavility of the series DC motor with unknown load-torque and unknown armature inductance is considered. The control technique of recursive, or backstepping, design is employed. Three cases are considered. In the first case, the system is assumed to be perfectly known. In the second case, the load torque is assumed to be unknown and a proportional-integral controller is developed to compensate for this unknown quantity. In the final case, it is assumed that two system parameters, load torque and armature inductance, are not known exactly, but vary from expected nominal values within a specified range. A robust control is designed to handle this case. The Lyapunov stavility criterion is applied ina ll three cases to prove the stability of the system under the developed control. The results are then verified through the use of computer simulation.
M.S.;
Electrical and Computer Engineering;
Engineering;
Electrical Engineering;
103 p.
vii, 103 leaves, bound : ill. ; 28 cm.
10
Pil, Anton Cyriel. "A rapid recursive experimental approach to integrated structure/control redesign of electromechanical systems." Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/39758.
11
Sanner, Robert M. (Robert Michael). "Stable adaptive control and recursive identification of nonlinear systems using radial Gaussian networks." Thesis, Massachusetts Institute of Technology, 1993. http://hdl.handle.net/1721.1/12711.
12
Huo, Xin. "Supporting Applications Involving Irregular Accesses and Recursive Control Flow on Emerging Parallel Environments." The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1400668968.
13
Wood, John D. "MIMO recursive least squares control algorithm for the AN/FPN-44A Loran-C transmitter." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1993. http://handle.dtic.mil/100.2/ADA274820.
14
Samaan, Malak Anees. "Toward faster and more accurate star sensors using recursive centroiding and star identification." Texas A&M University, 2003. http://hdl.handle.net/1969/433.
15
Zhang, Qi. "Magnetic Rendering: Magnetic Field Control for Haptic Interaction." Thesis, Université d'Ottawa / University of Ottawa, 2015. http://hdl.handle.net/10393/32613.
Abstract:
As a solution to mid-air haptic actuation with strong and continuous tactile force, Magnetic Rendering is presented as an intuitive haptic display method applying an electromagnet array to produce a magnetic field in mid-air where the force field can be felt as magnetic repulsive force exerted on the hand through the attached magnet discs. The magnetic field is generated by a specifically designed electromagnet array driven by direct current. By attaching small magnet discs on the hand, the tactile sensation can be perceived by the user. This method can provide a strong tactile force on multiple points covering user’s hand and avoid cumbersome attachments with wires, thus it is suitable for a co-located visual and haptic display. In my work, the detailed design of the electromagnet array for haptic rendering purposes is introduced, which is modelled and tested using Finite Element Method simulations. The model is characterized mathematically, and three methods for controlling the magnetic field are applied accordingly: direct control, system identification and adaptive control. The performance of the simulated model is evaluated in terms of magnetic field distribution, force strength, operation distance and force stiffness. The control algorithms are implemented and tested on a 3-by-3 and a 15-by-15 model, respectively. Simulations are performed on a 15-by-15 model to generate a haptic human face, which results in a smooth force field and accurate force exertion on the control points.
16
Kemp, Russell Stephen. "Pseudo-linear indentification and its application to adaptive control." Thesis, Virginia Tech, 1987. http://hdl.handle.net/10919/45810.
Abstract:
The method of Pseudo-Linear Identification (PLID) is presented as an explicitly linear approach to the joint state and parameter estimation problem. The convergence properties of the algorithm in the stochastic case are investigated through simulation and comparisons with popular methods are made. The method is then extended to allow the tracking of time-varying system parameters.
An adaptive control structure based upon this Trackingâ PLID algorithm is proposed which utilizes poleâ placement state variable feedback via Ackermann's formula. The capabilities of this adaptive control scheme are demonstrated by application to a full-order nonlinear aircraft simulation model where significant improvement is shown over fixed-gain controllers in the face of rapid plant changes.
Master of Science
17
Hamaguchi, Yushi. "Extended backward stochastic Volterra integral equations and their applications to time-inconsistent stochastic recursive control problems." Doctoral thesis, Kyoto University, 2021. http://hdl.handle.net/2433/263434.
18
Cheng, Qifeng. "Robust & stochastic model predictive control." Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:89da4934-9de7-4142-958e-513065189518.
Abstract:
In the thesis, two different model predictive control (MPC) strategies are investigated for linear systems with uncertainty in the presence of constraints: namely robust MPC and stochastic MPC. Firstly, a Youla Parameter is integrated into an efficient robust MPC algorithm. It is demonstrated that even in the constrained cases, the use of the Youla Parameter can desensitize the costs to the effect of uncertainty while not affecting the nominal performance, and hence it strengthens the robustness of the MPC strategy. Since the controller u = K x + c can offer many advantages and is used across the thesis, the work provides two solutions to the problem when the unconstrained nominal LQ-optimal feedback K cannot stabilise the whole class of system models. The work develops two stochastic tube approaches to account for probabilistic constraints. By using a semi closed-loop paradigm, the nominal and the error dynamics are analyzed separately, and this makes it possible to compute the tube scalings offline. First, ellipsoidal tubes are considered. The evolution for the tube scalings is simplified to be affine and using Markov Chain model, the probabilistic tube scalings can be calculated to tighten the constraints on the nominal. The online algorithm can be formulated into a quadratic programming (QP) problem and the MPC strategy is closed-loop stable. Following that, a direct way to compute the tube scalings is studied. It makes use of the information on the distribution of the uncertainty explicitly. The tubes do not take a particular shape but are defined implicitly by tightened constraints. This stochastic MPC strategy leads to a non-conservative performance in the sense that the probability of constraint violation can be as large as is allowed. It also ensures the recursive feasibility and closed-loop stability, and is extended to the output feedback case.
19
Hefny, Ahmed. "Efficient Methods for Prediction and Control in Partially Observable Environments." Research Showcase @ CMU, 2018. http://repository.cmu.edu/dissertations/1210.
Abstract:
State estimation and tracking (also known as filtering) is an integral part of any system performing inference in a partially observable environment, whether it is a robot that is gauging an environment through noisy sensors or a natural language processing system that is trying to model a sequence of characters without full knowledge of the syntactic or semantic state of the text. In this work, we develop a framework for constructing state estimators. The framework consists of a model class, referred to as predictive state models, and a learning algorithm, referred to as two-stage regression. Our framework is based on two key concepts: (1) predictive state: where our belief about the latent state of the environment is represented as a prediction of future observation features and (2) instrumental regression: where features of previous observations are used to remove sampling noise from future observation statistics, allowing for unbiased estimation of system dynamics. These two concepts allow us to develop efficient and tractable learning methods that reduce the unsupervised problem of learning an environment model to a supervised regression problem: first, a regressor is used to remove noise from future observation statistics. Then another regressor uses the denoised observation features to estimate the dynamics of the environment. We show that our proposed framework enjoys a number of theoretical and practical advantages over existing methods, and we demonstrate its efficacy in a prediction setting, where the task is to predict future observations, as well as a control setting, where the task is to optimize a control policy via reinforcement learning.
20
Wiklander, Jonas. "Performance comparison of the Extended Kalman Filter and the Recursive Prediction Error Method." Thesis, Linköping University, Department of Electrical Engineering, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-1832.
Abstract:
In several projects within ABB there is a need of state and parameter estimation for nonlinear dynamic systems. One example is a project investigating optimisation of gas turbine operation. In a gas turbine there are several parameters and states which are not measured, but are crucial for the performance. Such parameters are polytropic efficiencies in compressor and turbine stages, cooling mass flows, friction coefficients and temperatures. Different methods are being tested to solve this problem of system identification or parameter estimation. This thesis describes the implementation of such a method and compares it with previously implemented identification methods. The comparison is carried out in the context of parameter estimation in gas turbine models, a dynamic load model used in power systems as well as models of other dynamic systems. Both simulated and real plant measurements are used in the study.
21
Hong, Feng. "Multivariable predictive control development and application in food extrusion processes /." free to MU campus, to others for purchase, 1999. http://wwwlib.umi.com/cr/mo/fullcit?p9946262.
22
Gumpert, Ben Allen. "A recursive Gauss-Newton method for model independent eye-in-hand visual servoing / by Ben Allen Gumpert." Thesis, Georgia Institute of Technology, 2001. http://hdl.handle.net/1853/17260.
23
Palle, Sreeshailam. "Voltage Harmonic Control of Weak Utility Grid Through Distributed Energy Systems." University of Akron / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=akron1344998933.
24
Brus, Linda. "Nonlinear Identification and Control with Solar Energy Applications." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-8594.
25
Bueno, José Nuno Almeida Dias. "Controle robusto para robô manipulador espacial planar de base livre flutuante com dois braços." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/18/18153/tde-31082017-093441/.
Abstract:
Manipuladores robóticos têm ganhado cada vez mais importância em operações espaciais por poderem substituir humanos na realização de tarefas perigosas ou demasiadamente demoradas e repetitivas. Em destaque tem-se os manipuladores de base livre, por poderem ser acoplados a satélites ou estações espaciais e representarem um grande desafio para engenheiros de controle. Tais robôs possuem dois modos de operação: com base livre controlada e com base livre flutuante. No primeiro modo a base do manipulador tem atitude e translação controladas por jatos propulsores ou rodas de reação, de modo que o comportamento do robô se aproxima de um manipulador de base fixa. Porém, há um considerável consumo de combustível e energia elétrica, além de novos distúrbios que são inseridos no sistema. No segundo modo, considerado neste trabalho de mestrado, os controles da base são desligados durante a operação e ela pode mover-se livremente em resposta aos movimentos do braço. Embora tenha-se notável economia de combustível e energia elétrica, o acoplamento dinâmico entre base e braço deve ser considerado tanto na modelagem como no projeto do controlador. Para modelar o robô espacial considerado neste projeto foi aplicado o método do Manipulador Dinamicamente Equivalente, que mapeia um manipulador de base livre flutuante através de um robô sub-atuado de base fixa. Dessa forma é possível utilizar sobre robôs espaciais técnicas de controle já desenvolvidas para manipuladores terrestres. Este trabalho trata da análise de controladores robustos e adaptativo aplicados sobre um manipulador planar de base livre flutuante com dois braços para realizar a tarefa de seguimento de trajetórias definidas no espaço de tarefa. Os sistemas de controle considerados foram: Regulador Linear Quadrático Recursivo Robusto (RLQR), controlador H-infinito robusto e controlador adaptativo com modos deslizantes. Os resultados mostraram que os controladores apresentaram desempenhos distintos mas ainda assim foram capazes de realizar a tarefa de seguir trajetórias no espaço de trabalho com erros de acompanhamento bastante pequenos. Foi elaborada também uma comparação quantitativa através de índices de desempenho considerando integral de torques e norma L2 de erros de acompanhamento.Robotic manipulators gained greater importance in space operations by being able to replace humans in dangerous or very long and repetitive tasks. Free-floating manipulators are highlighted, because they can be coupled to satellites or space stations and represent a great challenge to control engineers. These robots have two operation modes: controlled base and free-floating base. In the first mode, the base has its attitude and translation controlled by propulsion jets or reaction wheels, so that the robot behavior is similar to a fixed-base manipulator. However, there is considerable fuel and electrical energy consumption, besides additional disturbances inserted in the system. In the second mode, which is considered in this work, the base is not controlled during operation and is able to move freely in response to movements of the arm. Even though there is a remarkable fuel and electrical energy saving, the dynamic coupling between base and arm must be taken into account during modelling and controller design. To model the space manipulator considered in this work the Dynamically Equivalent Manipulator method was used, which maps a free-floating manipulator into a underactuated fixed-base manipulator. Thus, it is possible to apply known control techniques for terrestrial manipulators on free-floating ones. This work discusses robust and adaptive controllers applied on a planar dual-arm free-floating space manipulator in order to track trajectories defined in the workspace. The considered control systems are: Robust Recursive Linear Quadratic Regulator, Robust H-infinity and Adaptive Sliding Modes. Results showed that the controllers had distinct performances but were still able to perform trajectory tracking in workspace with very small tracking errors. A quantitative comparison was also elaborated with performance indexes considering integral of torques and L2 norm of tracking errors.
26
Tayamon, Soma. "Nonlinear System Identification and Control Applied to Selective Catalytic Reduction Systems." Doctoral thesis, Uppsala universitet, Avdelningen för systemteknik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-229148.
Abstract:
The stringent regulations of emission levels from heavy duty vehicles create a demand for new methods for reducing harmful emissions from diesel engines. This thesis deals with the modelling of the nitrogen oxide (NOx) emissions from heavy duty vehicles using a selective catalyst as an aftertreatment system, utilising ammonia (NH3) for its reduction. The process of the selective catalytic reduction (SCR) is nonlinear, since the result of the chemical reactions involved depends on the load operating point and the temperature. The purpose of this thesis is to investigate different methods for nonlinear system identification of SCR systems with control applications in mind. The main focus of the thesis is on finding suitable techniques for effective NOx reduction without the need of over dosage of ammonia. By using data collected from a simulator together with real measured data, new black-box identification techniques are developed. Scaling and convergence properties of the proposed algorithms are analysed theoretically. Some of the resulting models are used for controller development using e.g. feedback linearisation techniques, followed by validation in a simulator environment. The benefits of nonlinear modelling and control of the SCR system are highlighted in a comparison with control based on linear models of the system. Further, a multiple model approach is investigated for simultaneous control of NOx and tailpipe ammonia. The results indicate an improvement in terms of ammonia slip reduction in comparison with models that do not take the ammonia slip into account. Another approach to NOx reduction is achieved by controlling the SCR temperature using techniques developed for LPV systems. The results indicate a reduction of the accumulated NOx.
27
Halldin, Axel. "Control of a Multivariable Lighting System." Thesis, Linköpings universitet, Reglerteknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-134913.
Abstract:
This master’s thesis examines how a small MIMO lighting system can be identified and controlled. Two approaches are examined and compared; the first approach is a dynamic model using state space representation, where the system identification technique is Recursive Least Square, RLS, and the controller is an LQG controller; the second approach is a static model derived from the physical properties of light and a feedback feed-forward controller consisting of a PI controller coupled with a Control Allocation, CA, technique. For the studied system, the CA-PI approach significantly outperforms the LQG-RLS approach, which leads to the conclusion that the system’s static properties are predominant compared to the dynamic properties.
28
Doubleday, Kevin. "Generation of Individualized Treatment Decision Tree Algorithm with Application to Randomized Control Trials and Electronic Medical Record Data." Thesis, The University of Arizona, 2016. http://hdl.handle.net/10150/613559.
Abstract:
With new treatments and novel technology available, personalized medicine has become a key topic in the new era of healthcare. Traditional statistical methods for personalized medicine and subgroup identification primarily focus on single treatment or two arm randomized control trials (RCTs). With restricted inclusion and exclusion criteria, data from RCTs may not reflect real world treatment effectiveness. However, electronic medical records (EMR) offers an alternative venue. In this paper, we propose a general framework to identify individualized treatment rule (ITR), which connects the subgroup identification methods and ITR. It is applicable to both RCT and EMR data. Given the large scale of EMR datasets, we develop a recursive partitioning algorithm to solve the problem (ITR-Tree). A variable importance measure is also developed for personalized medicine using random forest. We demonstrate our method through simulations, and apply ITR-Tree to datasets from diabetes studies using both RCT and EMR data. Software package is available at https://github.com/jinjinzhou/ITR.Tree.
29
Maciel, Allan James Ferreira. "CONVERGÊNCIA DO ESTIMADOR RLS PARA ALGORITMOS DE PROGRAMAÇÃO DINÂMICA HEURÍSTICA." Universidade Federal do Maranhão, 2012. http://tedebc.ufma.br:8080/jspui/handle/tede/494.
Abstract:
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The union of methodologies for optimal control and dynamics programming has stimulated the development of algorithms for realization of discrete control systems of the type linear quadratic regulator (DLQR). The methodology is based on reinforcement learning methods based on temporal differences and approximate dynamic programming. The proposed method combines the approach of the value function by method RLS (recursive least squares) and approximate policy iteration schemes heuristic dynamic programming (HDP). The approach is directed to the assessment of convergence of the solution DLQR and the heuristic weighting matrices and of the utility function associated with DLQR. The investigation of convergence properties related to consistency, persistent excitation and polarization of the RLS estimator is performed. The methodology involved in a project achievements online DLQR controllers and is evaluated in a fourth order multivariable dynamic system.
A união das metodologias de controle ótimo e de programação dinâmica tem impulsionado o desenvolvimento de algoritmos para realizações de sistemas de controle discreto do tipo regulador linear quadrático (DLQR). A metodologia utilizada neste trabalho é fundamentada sobre métodos de aprendizagem por reforço baseados em diferenças temporais e programação dinâmica aproximada. O método proposto combina a aproximação da função valor através do método RLS (mínimos quadrados recursivos) e iteração de política aproximada em esquemas de programação dinâmica heurística (HDP). A abordagem é orientada para a avaliação da convergência da solução DLQR e para a sintonia heurística das matrizes de ponderação e da função de utilidade associada ao DLQR. É realizada a investigação das propriedades de convergência relacionadas à consistência, excitação persistente e polarização do estimador RLS. A metodologia contempla realizações de projetos de forma online de controladores DLQR e é avaliada em um sistema dinâmico multivariável de quarta ordem.
30
Lanhede, Daniel. "Non-parametric Statistical Process Control : Evaluation and Implementation of Methods for Statistical Process Control at GE Healthcare, Umeå." Thesis, Umeå universitet, Institutionen för matematik och matematisk statistik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-104512.
Abstract:
Statistical process control (SPC) is a toolbox to detect changes in the output of a process distribution. It can serve as a valuable resource to maintain high quality in a manufacturing process. This report is based on the work on evaluating and implementing methods for SPC in the process of chromatography instrument manufacturing at GE Healthcare, Umeå. To handle low volume and non-normally distributed process output data, non-parametric methods are considered. Eight control charts, three for for Phase I analysis, and five for Phase II analysis, are evaluated in this study. The usability of the charts are assessed based on ease of interpretation and the performance to detect distributional changes. The later is evaluated with simulations. The result of the project is the implementation of the RS/P-chart, suggested by Capizzi et al (2013), for Phase I analysis. Of the considered Phase I methods (and simulation scenarios), the RS/P-chart has the highest overall probability, of detecting a variety of distributional changes. Further, the RS/P-chart is easily interpreted, facilitating the analysis. For Phase II analysis, the use of two control charts, one based on the Mann-Whitney U statistic, suggested by Chakraborti et al (2008), and one on the Mood test statistic for dispersion, suggested by Ghute et al (2014), have been implemented. These are chosen mainly based on the ease of interpretation. To reduce the detection time for changes in the process distribution, the change-point chart based on the Cramer Von Mises statistic, suggested by Ross et al (2012), could be used instead. Using single observations, instead of larger samples, this chart is updated more frequently. However, this efficiently increases the false alarm rate and the chart is also considered much more difficult to interpret for the SPC practitioner.Statistisk processkontroll (SPC) är en samling verktyg för att upptäcka förändringar, i fördelningen, hos utfallen i en process. Det kan fungera som en värdefull resurs för att upprätthålla en hög kvalitet i en tillverkningsprocess. Denna rapport är baserad på arbetet med att utvärdera och implementera metoder för SPC i en monteringsprocess av kromatografiinstrument på GE Healthcare, Umeå. Åtta styrdiagram, tre för för fas I analys, och fem för fas II analys, studeras i denna rapport. Användbarheten hos styrdiagrammen bedöms efter hur enkla de är att tolka och förmågan att upptäcka fördelningsförändringar. Den senare utvärderas med simuleringar. Resultatet av projektet är införandet av RS/P-metod, utvecklad av Capizzi et al (2013), för analysen i fas I. Av de utvärderade metoderna, (och simuleringsscenarier), har RS/P-diagrammet den högsta övergripande sannolikheten, för att upptäcka en mängd olika fördelningsförändringar. Vidare är metodens grafiska diagram lätt att tolka, vilket underlättar analysen. För fas II analys, har två styrdiagram, ett baserat på Mann-Whitney's U teststatistika, som föreslagits av Chakraborti et al (2008), och ett på Mood's teststatistika för spridning, som föreslagits av Ghute et al (2014), implementerats. Styrkan i dessa styrdiagram ligger främst i dess enkla tolkning. För snabbare identifiering av processförändringar kan styrdiagrammet baserat på Cramer von Mises teststatistika, som föreslagits av Ross et al (2012), användas. Baserat på enskilda observationer, istället för stickprov, har styrdiagrammet en högre uppdateringsfrekvens. Detta leder dock till ett ökat antal falska larm och styrdiagrammet anses dessutom vara avsevärt mycket svårare att tolka för SPC-utövaren.
31
Tambara, Rodrigo Varella. "Um controlador adaptativo robusto aplicado a conversores estáticos conectados à rede elétrica através de filtro LCL." Universidade Federal de Santa Maria, 2014. http://repositorio.ufsm.br/handle/1/3686.
Abstract:
Conselho Nacional de Desenvolvimento Científico e TecnológicoThis Thesis deals with the development of a novel robust model reference adaptive controller (RMRAC), in discrete-time applied to grid-connected systems using LCL filter. This controller uses a modified robust parameters identifier based on a recursive least-squares algorithm. Two control structures are analyzed: state feedback approach and input-output approach. The robust stability analysis of the controller is presented including unmodeled dynamics. Thus, through these analyses, constraints design, in discrete-time, are obtained. For the validation of the proposed control algorithm, simulation and experimental results of a grid-connected power converter with LCL-filter, with current control, are presented.
Esta Tese de Doutorado apresenta o desenvolvimento de um novo controlador adaptativo por modelo de referência, totalmente desenvolvido em tempo discreto, aplicado a sistemas conectados à rede de energia elétrica empregando filtro LCL. Este controlador utiliza um identificador de parâmetros modificado robusto baseado no método dos mínimos quadrados recursivos. Em relação à estrutura do controlador, a abordagem por realimentação de estados e a abordagem entrada-saída são utilizadas. A análise de estabilidade robusta do controlador é apresentada incluindo dinâmicas não-modeladas. Por meio destas análises, restrições de projeto (em tempo discreto) são obtidas. Para a validação do algoritmo proposto, resultados de simulação e experimentais do sistema de controle de corrente em um conversor conectado à rede de energia elétrica com filtro LCL são apresentados.
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Jägerback, Peter. "En indirekt metod för adaptiv reglering av en helikopter." Thesis, Linköping University, Linköping University, The Institute of Technology, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-17637.
Abstract:
When a helicopter is flying, the dynamics vary depending on, for example, speed and position. Hence, a time-invariant linear model cannot describe its properties under all flight conditions. It is therefore desirable to update the linear helicopter model continuously during the flight. In this thesis, two different recursive estimation methods are presented, LMS (Least Mean Square) and adaptation with a Kalman filter. The main purpose of the system estimation is to get a model which can be used for feedback control. In this report, the estimated model will be used to create a LQ controller with the task of keeping the output signal as close to the reference signal as possible.Simulations in this report show that adaptive feedback control can be used to control a helicopter's angular velocities and that the possibility to use an adaptive control algorithm in a real future helicopter is good.
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Madkour, A. A. M., M. Alamgir Hossain, Keshav P. Dahal, and H. Yu. "Real-time system identification using intelligent algorithms." IEEE, 2004. http://hdl.handle.net/10454/2471.
Abstract:
This research presents an investigation into
the development of real time system identification using
intelligent algorithms. A simulation platform of a flexible
beam vibration using finite difference (FD) method is
used to demonstrate the real time capabilities of the
identification algorithms. A number of approaches and
algorithms for on line system identifications are explored
and evaluated to demonstrate the merits of the algorithms
for real time implementation. These approaches include
identification using (a) traditional recursive least square
(RLS) filter, (b) Genetic Algorithms (GAs) and (c)
adaptive Neuro_Fuzzy (ANFIS) model. The above
algorithms are used to estimate a linear discrete second
order model for the flexible beam vibration. The model is
implemented, tested and validated to evaluate and
demonstrate the merits of the algorithms for real time
system identification. Finally, a comparative performance
of error convergence and real time computational
complexity of the algorithms is presented and discussed
through a set of experiments.
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Arslan, Huseyin Gokseli. "Adaptive cache aware multiprocessor scheduling framework." Thesis, Queensland University of Technology, 2011. https://eprints.qut.edu.au/47602/1/Huseyin_Arslan_Thesis.pdf.
Abstract:
Computer resource allocation represents a significant challenge particularly for multiprocessor systems, which consist of shared computing resources to be allocated among co-runner processes and threads. While an efficient resource allocation would result in a highly efficient and stable overall multiprocessor system and individual thread performance, ineffective poor resource allocation causes significant performance bottlenecks even for the system with high computing resources. This thesis proposes a cache aware adaptive closed loop scheduling framework as an efficient resource allocation strategy for the highly dynamic resource management problem, which requires instant estimation of highly uncertain and unpredictable resource patterns. Many different approaches to this highly dynamic resource allocation problem have been developed but neither the dynamic nature nor the time-varying and uncertain characteristics of the resource allocation problem is well considered. These approaches facilitate either static and dynamic optimization methods or advanced scheduling algorithms such as the Proportional Fair (PFair) scheduling algorithm. Some of these approaches, which consider the dynamic nature of multiprocessor systems, apply only a basic closed loop system; hence, they fail to take the time-varying and uncertainty of the system into account. Therefore, further research into the multiprocessor resource allocation is required. Our closed loop cache aware adaptive scheduling framework takes the resource availability and the resource usage patterns into account by measuring time-varying factors such as cache miss counts, stalls and instruction counts. More specifically, the cache usage pattern of the thread is identified using QR recursive least square algorithm (RLS) and cache miss count time series statistics. For the identified cache resource dynamics, our closed loop cache aware adaptive scheduling framework enforces instruction fairness for the threads. Fairness in the context of our research project is defined as a resource allocation equity, which reduces corunner thread dependence in a shared resource environment. In this way, instruction count degradation due to shared cache resource conflicts is overcome. In this respect, our closed loop cache aware adaptive scheduling framework contributes to the research field in two major and three minor aspects. The two major contributions lead to the cache aware scheduling system. The first major contribution is the development of the execution fairness algorithm, which degrades the co-runner cache impact on the thread performance. The second contribution is the development of relevant mathematical models, such as thread execution pattern and cache access pattern models, which in fact formulate the execution fairness algorithm in terms of mathematical quantities. Following the development of the cache aware scheduling system, our adaptive self-tuning control framework is constructed to add an adaptive closed loop aspect to the cache aware scheduling system. This control framework in fact consists of two main components: the parameter estimator, and the controller design module. The first minor contribution is the development of the parameter estimators; the QR Recursive Least Square(RLS) algorithm is applied into our closed loop cache aware adaptive scheduling framework to estimate highly uncertain and time-varying cache resource patterns of threads. The second minor contribution is the designing of a controller design module; the algebraic controller design algorithm, Pole Placement, is utilized to design the relevant controller, which is able to provide desired timevarying control action. The adaptive self-tuning control framework and cache aware scheduling system in fact constitute our final framework, closed loop cache aware adaptive scheduling framework. The third minor contribution is to validate this cache aware adaptive closed loop scheduling framework efficiency in overwhelming the co-runner cache dependency. The timeseries statistical counters are developed for M-Sim Multi-Core Simulator; and the theoretical findings and mathematical formulations are applied as MATLAB m-file software codes. In this way, the overall framework is tested and experiment outcomes are analyzed. According to our experiment outcomes, it is concluded that our closed loop cache aware adaptive scheduling framework successfully drives co-runner cache dependent thread instruction count to co-runner independent instruction count with an error margin up to 25% in case cache is highly utilized. In addition, thread cache access pattern is also estimated with 75% accuracy.
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Yu, Rui. "A REDUNDANT MONITORING SYSTEM FOR HUMAN WELDER OPERATION USING IMU AND VISION SENSORS." UKnowledge, 2018. https://uknowledge.uky.edu/ece_etds/128.
Abstract:
In manual control, the welding gun’s moving speed can significantly influence the welding results and critical welding operations usually require welders to concentrate consistently in order to react rapidly and accurately. However, human welders always have some habitual action which can have some subtle influence the welding process. It takes countless hours to train an experienced human welder. Using vision and IMU sensor will be able to set up a system and allow the worker got more accurate visual feedback like an experienced worker.
The problem is that monitor and measuring of the control process not always easy under a complex working environment like welding. In this thesis, a new method is developed that use two different methods to compensate each other to obtain accurate monitoring results. Vision sensor and IMU sensor both developed to obtain the accurate data from the control process in real-time but don’t influence other. Although both vision and IMU sensor has their own limits, they also have their own advantage which can contribute to the measuring system.
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Silva, Paulo César da. "PI-MQR adaptativo aplicado a um motor de indução trifásico utilizando a plataforma DSPACE1103." Universidade do Estado de Santa Catarina, 2015. http://tede.udesc.br/handle/handle/1879.
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Previous issue date: 2015-07-10Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
The electrical parameters of three-phase induction motors vary according to their operating point, with the temperature and also with the natural machine degradation. Since the design regulators are typically performed based on linear and simplified equations of the machine, the parametric variation can cause unwanted responses, since the motor behavior is non-linear and time variant. Thus, it is proposed in this work carry the identification of the electrical parameters of the induction motor using the estimator called Least Squares Recursive (RLS). Thus, with the parametric data updated every sampling period can be recalculated in real time the gains of the regulators are designed for controlling the induction machine and make minor mismatches. The experimental results were obtained with the processing performed by dSPACE hardware (DS1103), which has an interface with Matlab/Simulink, facilitating the use by the user and reducing the time taken for testing bench. The results of numerical and practical simulations show a comparison between the mesh proposal, the parametric identification and update of the gains of the controllers (adaptive control) and the mesh with controllers with fixed gains.
Os parâmetros elétricos do motor de indução trifásico variam conforme o seu ponto de operação, com a temperatura e também com a degradação natural da máquina. Visto que o projeto de reguladores são tipicamente realizados com base em equações lineares e simplicadas da máquina, a variação paramétrica pode causar respostas indesejadas, pois o comportamento do motor é não-linear e variante no tempo. Desta forma propõe-se neste trabalho realizar a identificação dos parâmetros elétricos do motor de indução, utilizando o estimador denominado de Mínimos Quadrados Recursivos (MQR). Assim, com os dados paramétricos atualizados a cada período de amostragem, pode-se recalcular em tempo real, os ganhos dos reguladores que são projetados para o controle da máquina de indução e tornar os descasamentos menores. Os resultados experimentais foram obtidos com o processamento realizado pelo hardware dSPACE (DS1103), que possui uma interface com o Matlab/Simulink, facilitando a utilização por parte do usuário e reduzindo o tempo dispendido para os testes em bancada. Os resultados de simulações numéricas e práticos apresentam uma comparação entre a malha proposta, com a identificação paramétrica e atualiza ção dos ganhos dos controladores (controle adaptativo) e a malha com controladores com ganhos fixos.
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Ferreira, Ernesto Franklin Marçal. "Melhorias de estabilidade numérica e custo computacional de aproximadores de funções valor de estado baseados em estimadores RLS para projeto online de sistemas de controle HDP-DLQR." Universidade Federal do Maranhão, 2016. http://tedebc.ufma.br:8080/jspui/handle/tede/1687.
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The development and the numerical stability analysis of a new adaptive critic algorithm to approximate the state-value function for online discrete linear quadratic regulator (DLQR) optimal control system design based on heuristic dynamic programming (HDP) are presented in this work. The proposed algorithm makes use of unitary transformations and QR decomposition methods to improve the online learning e-ciency in the critic network through the recursive least-squares (RLS) approach. The developed learning strategy provides computational performance improvements in terms of numerical stability and computational cost which aim at making possible the implementations in real time of optimal control design methodology based upon actor-critic reinforcement learning paradigms. The convergence behavior and numerical stability of the proposed online algorithm, called RLSµ-QR-HDP-DLQR, are evaluated by computational simulations in three Multiple-Input and Multiple-Output (MIMO) models, that represent the automatic pilot of an F-16 aircraft of third order, a fourth order RLC circuit with two input voltages and two controllable voltage levels, and a doubly-fed induction generator with six inputs and six outputs for wind energy conversion systems.
Neste trabalho, apresenta-se o desenvolvimento e a análise da estabilidade numérica de um novo algoritmo crítico adaptativo para aproximar a função valor de estado para o projeto do sistema de controle ótimo online, utilizando o regulador linear quadrático discreto (DLQR), com base em programação dinâmica heurística (HDP). O algoritmo proposto faz uso de transformações unitárias e métodos de decomposição QR para melhorar a e-ciência da aprendizagem online na rede crítica por meio da abordagem dos mínimos quadrados recursivos (RLS). A estratégia de aprendizagem desenvolvida fornece melhorias no desempenho computacional em termos de estabilidade numérica e custo computacional, que visam tornar possíveis as implementações em tempo real da metodologia do projeto de controle ótimo com base em paradigmas de aprendizado por reforço ator-crítico. O comportamento de convergência e estabilidade numérica do algoritmo online proposto, denominado RLSµ-QR-HDP-DLQR, são avaliados por meio de simulações computacionais em três modelos Múltiplas-Entradas e Múltiplas-Saídas (MIMO), que representam o piloto automático de uma aeronave F-16 de terceira ordem, um circuito de quarta ordem RLC com duas tensões de entrada e dois níveis de tensão controláveis, e um gerador de indução duplamente alimentados com seis entradas e seis saídas para sistemas de conversão de energia eólica.
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RÊGO, Patrícia Helena Moraes. "Aprendizagem por Reforço e Programação Dinâmica Aproximada para Controle Ótimo: Uma Abordagem para o Projeto Online do Regulador Linear Quadrático Discreto com Programação Dinâmica Heurística Dependente de Estado e Ação." Universidade Federal do Maranhão, 2014. http://tedebc.ufma.br:8080/jspui/handle/tede/1879.
Abstract:
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In this thesis a proposal of an uni ed approach of dynamic programming, reinforcement learning and function approximation theories aiming at the development of methods and algorithms for design of optimal control systems is presented. This approach is presented in the approximate dynamic programming context that allows approximating the optimal feedback solution as to reduce the computational complexity associated to the conventional dynamic programming methods for optimal control of multivariable systems. Speci cally, in the state and action dependent heuristic dynamic programming framework, this proposal is oriented for the development of online approximated solutions, numerically stable, of the Riccati-type Hamilton-Jacobi-Bellman equation associated to the discrete linear quadratic regulator problem which is based on a formulation that combines value function estimates by means of a RLS (Recursive Least-Squares) structure, temporal di erences and policy improvements. The development of the proposed methodologies, in this work, is focused mainly on the UDU T factorization that is inserted in this framework to improve the RLS estimation process of optimal decision policies of the discrete linear quadratic regulator, by circumventing convergence and numerical stability problems related to the covariance matrix ill-conditioning of the RLS approach.
Apresenta-se nesta tese uma proposta de uma abordagem uni cada de teorias de programação dinâmica, aprendizagem por reforço e aproximação de função que tem por objetivo o desenvolvimento de métodos e algoritmos para projeto online de sistemas de controle ótimo. Esta abordagem é apresentada no contexto de programação dinâmica aproximada que permite aproximar a solução de realimentação ótima de modo a reduzir a complexidade computacional associada com métodos convencionais de programação dinâmica para controle ótimo de sistemas multivariáveis. Especi camente, no quadro de programação dinâmica heurística e programação dinâmica heurística dependente de ação, esta proposta é orientada para o desenvolvimento de soluções aproximadas online, numericamente estáveis, da equação de Hamilton-Jacobi-Bellman do tipo Riccati associada ao problema do regulador linear quadrático discreto que tem por base uma formulação que combina estimativas da função valor por meio de uma estrutura RLS (do inglês Recursive Least-Squares), diferenças temporais e melhorias de política. O desenvolvimento das metodologias propostas, neste trabalho, tem seu foco principal voltado para a fatoração UDU T que é inserida neste quadro para melhorar o processo de estimação RLS de políticas de decisão ótimas do regulador linear quadrá- tico discreto, contornando-se problemas de convergência e estabilidade numérica relacionados com o mal condicionamento da matriz de covariância da abordagem RLS.
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Khereddine, Rafik. "Méthode adaptative de contrôle logique et de test de circuits AMS/FR." Phd thesis, Université de Grenoble, 2011. http://tel.archives-ouvertes.fr/tel-00647169.
Abstract:
Les technologies microélectroniques ainsi que les outils de CAO actuels permettent la conception de plus en plus rapide de circuits et systèmes intégrés très complexes. L'un des plus importants problèmes rencontrés est de gérer la complexité en terme de nombre de transistors présents dans le système à manipuler ainsi qu'en terme de diversité des composants, dans la mesure où les systèmes actuels intègrent, sur un même support de type SiP ou bien SoC, de plus en plus de blocs fonctionnels hétérogènes. Le but de cette thèse est la recherche de nouvelles techniques de test qui mettent à contribution les ressources embarquées pour le test et le contrôle des modules AMS et RF. L'idée principale est de mettre en oeuvre pour ces composantes des méthodes de test et de contrôle suffisamment simples pour que les ressources numériques embarquées puissent permettre leur implémentation à faible coût. Les techniques proposées utilisent des modèles de représentation auto-régressifs qui prennent en comptes les non linéarités spécifiques à ce type de modules. Les paramètres du modèle comportemental du système sont utilisés pour la prédiction des performances du système qui sont nécessaire pour l'élaboration de la signature de test et le contrôle de la consommation du circuit. Deux démonstrateurs ont été mis en place pour valider la technique proposée : une chaine RF conçue au sein du groupe RMS et un accéléromètre de type MMA7361L.
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Evestedt, Magnus. "Parameter and State Estimation with Information-rich Signals." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis Acta Universitatis Upsaliensis, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-8315.
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Mattei, Giovanni. "Robust nonlinear control : from continuous time to sampled-data with aerospace applications." Thesis, Paris 11, 2015. http://www.theses.fr/2015PA112025/document.
Abstract:
La thèse porte sur le développement des techniques non linéaires robustes de stabilisation et commande des systèmes avec perturbations de model. D’abord, on introduit les concepts de base de stabilité et stabilisabilité robuste dans le contexte des systèmes non linéaires. Ensuite, on présente une méthodologie de stabilisation par retour d’état en présence d’incertitudes qui ne sont pas dans l’image de la commande («unmatched»). L’approche récursive du «backstepping» permet de compenser les perturbations «unmatched» et de construire une fonction de Lyapunov contrôlée robuste, utilisable pour le calcul ultérieur d’un compensateur des incertitudes dans l’image de la commande («matched»). Le contrôleur obtenu est appelé «recursive Lyapunov redesign». Ensuite, on introduit la technique de stabilisation par «Immersion & Invariance» comme outil pour rendre un donné contrôleur non linéaire, robuste par rapport à dynamiques non modelées. La première technique de contrôle non linéaire robuste proposée est appliquée au projet d’un autopilote pour un missile air-air et au développement d’une loi de commande d’attitude pour un satellite avec appendices flexibles. L’efficacité du «recursive Lyapunov redesign» est mis en évidence dans le deux cas d’étude considérés. En parallèle, on propose une méthode systématique de calcul des termes incertains basée sur un modèle déterministe d’incertitude. La partie finale du travail de thèse est relative à la stabilisation des systèmes sous échantillonnage. En particulier, on reformule, dans le contexte digital, la technique d’Immersion et Invariance. En premier lieu, on propose des solutions constructives en temps continu dans le cas d’une classe spéciale des systèmes en forme triangulaire «feedback form», au moyen de «backstepping» et d’arguments de domination non linéaire. L’implantation numérique est basée sur une loi multi-échelles, dont l’existence est garantie pour la classe des systèmes considérée. Le contrôleur digital assure la propriété d’attractivité et des trajectoires bornées. La loi de commande, calculée par approximation finie d’un développement asymptotique, est validée en simulation de deux exemples académiques et deux systèmes physiques, le pendule inversé sur un chariot et le satellite rigideThe dissertation deals with the problems of stabilization and control of nonlinear systems with deterministic model uncertainties. First, in the context of uncertain systems analysis, we introduce and explain the basic concepts of robust stability and stabilizability. Then, we propose a method of stabilization via state-feedback in presence of unmatched uncertainties in the dynamics. The recursive backstepping approach allows to compensate the uncertain terms acting outside the control span and to construct a robust control Lyapunov function, which is exploited in the subsequent design of a compensator for the matched uncertainties. The obtained controller is called recursive Lyapunov redesign. Next, we introduce the stabilization technique through Immersion \& Invariance (I\&I) as a tool to improve the robustness of a given nonlinear controller with respect to unmodeled dynamics. The recursive Lyapunov redesign is then applied to the attitude stabilization of a spacecraft with flexible appendages and to the autopilot design of an asymmetric air-to-air missile. Contextually, we develop a systematic method to rapidly evaluate the aerodynamic perturbation terms exploiting the deterministic model of the uncertainty. The effectiveness of the proposed controller is highlighted through several simulations in the second case-study considered. In the final part of the work, the technique of I\& I is reformulated in the digital setting in the case of a special class of systems in feedback form, for which constructive continuous-time solutions exist, by means of backstepping and nonlinear domination arguments. The sampled-data implementation is based on a multi-rate control solution, whose existence is guaranteed for the class of systems considered. The digital controller guarantees, under sampling, the properties of manifold attractivity and trajectory boundedness. The control law, computed by finite approximation of a series expansion, is finally validated through numerical simulations in two academic examples and in two case-studies, namely the cart-pendulum system and the rigid spacecraft
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Nyberg, Tobias. "Torque-Based Load Estimation for Passenger Vehicles." Thesis, Linköpings universitet, Reglerteknik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-179208.
Abstract:
An accurate estimate of the mass of a passenger vehicle is important for several safety systems and environmental aspects. In this thesis, an algorithm for estimating the mass of a passenger vehicle using the recursive least squares methodis presented. The algorithm is based on a physical model of the vehicle and is designed to be able to run in real-time onboard a vehicle and uses the wheel torque signal calculated in the electrical control unit in the engine. Therefore no estimation of the powertrain is needed. This is one contribution that distinguishes this thesis from previous work on the same topic, which has used the engine torque. The benefit of this is that no estimation of the dynamics in the powertrain is needed. The drawback of using this method is that the algorithm is dependenton the accuracy of the estimation done in the engine electrical control unit. Two different versions of the recursive least squares method (RLS) have been developed - one with a single forgetting factor and one with two forgetting factors. The estimation performance of the two versions are compared on several different real-world driving scenarios, which include driving on country roads, highways, and city roads, and different loads in the vehicle. The algorithm with a single forgetting factor estimates the mass with an average error for all tests of 4.42% and the algorithm with multiple forgetting factors estimates the mass with an average error of 4.15 %, which is in line with state-of-the-art algorithms that are presented in other studies. In a sensitivity analysis, it is shown that the algorithms are robust to changes in the drag coefficient. The single forgetting factor algorithm is robust to changes in the rolling resistance coefficient whereas the multiple forgetting factor algorithm needs the rolling resistance coefficient to be estimated with fairly good accuracy. Both versions of the algorithm need to know the wheel radius with an accuracy of 90 %. The results show that the algorithms estimate the mass accurately for all three different driving scenarios and estimate highway roads best with an average error of 2.83 % and 2.69 % for the single forgetting factor algorithm and the multiple forgetting factor algorithm, respectively. The results indicate it is possible to use either algorithm in a real-world scenario, where the choice of which algorithm depends on sought-after robustness.
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Kalivoda, Jakub. "Adaptivní řízení varny malého pivovaru." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2014. http://www.nusl.cz/ntk/nusl-220959.
Abstract:
This final thesis deals with adaptive control of small brewery. Contains a short description of brewing technology and adaptive control. Includes design of small brawery and control system based on STM32F407 Cortex-M4 microcontroller. For online identification is used Recursive Least Squares Method. The controller function perform a modified PSD controller with filtered derivative component, reducing the first overshot and dynamic antiwindup. The proposed adaptive controller is implemented into microcontroller. Created device i used for semi-automatic beer production.
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Bush, V. J. "Recursion transformations for run-time control of parallel computations." Thesis, University of Manchester, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.382888.
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Bodin, Camilla. "Automatic Flight Maneuver Identification Using Machine Learning Methods." Thesis, Linköpings universitet, Reglerteknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-165844.
Abstract:
This thesis proposes a general approach to solve the offline flight-maneuver identification problem using machine learning methods. The purpose of the study was to provide means for the aircraft professionals at the flight test and verification department of Saab Aeronautics to automate the procedure of analyzing flight test data. The suggested approach succeeded in generating binary classifiers and multiclass classifiers that identified six flight maneuvers of different complexity from real flight test data. The binary classifiers solved the problem of identifying one maneuver from flight test data at a time, while the multiclass classifiers solved the problem of identifying several maneuvers from flight test data simultaneously. To achieve these results, the difficulties that this time series classification problem entailed were simplified by using different strategies. One strategy was to develop a maneuver extraction algorithm that used handcrafted rules. Another strategy was to represent the time series data by statistical measures. There was also an issue of an imbalanced dataset, where one class far outweighed others in number of samples. This was solved by using a modified oversampling method on the dataset that was used for training. Logistic Regression, Support Vector Machines with both linear and nonlinear kernels, and Artifical Neural Networks were explored, where the hyperparameters for each machine learning algorithm were chosen during model estimation by 4-fold cross-validation and solving an optimization problem based on important performance metrics. A feature selection algorithm was also used during model estimation to evaluate how the performance changes depending on how many features were used. The machine learning models were then evaluated on test data consisting of 24 flight tests. The results given by the test data set showed that the simplifications done were reasonable, but the maneuver extraction algorithm could sometimes fail. Some maneuvers were easier to identify than others and the linear machine learning models resulted in a poor fit to the more complex classes. In conclusion, both binary classifiers and multiclass classifiers could be used to solve the flight maneuver identification problem, and solving a hyperparameter optimization problem boosted the performance of the finalized models. Nonlinear classifiers performed the best on average across all explored maneuvers.
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Zuo, Jian. "The Frequency Monitor Network (FNET) Design and Situation Awareness Algorithm Development." Diss., Virginia Tech, 2008. http://hdl.handle.net/10919/26721.
Abstract:
Wide Area Measurements (WAMs) have been widely used in the energy management system (EMS) of power system for monitoring, operation and control. In recent years, the advent of synchronized Phasor Measurements Unit (PMU) has added another dimension to the field of wide-area measurement. However, the high cost of the PMU, which includes the manufacture and deployment fee, is a hurdle to the wide use of the PMU in power systems. Unlike traditional PMUs, the frequency monitoring network (FNET) developed by the Virginia Tech Power IT lab is an Internetâ based, GPSâ synchronized, wide-area frequency monitoring network deployed at the distribution level, providing a low-cost and easily deployable WAMs solution. In this dissertation, the research work can be categorized into two parts: FNET Design and Situation Awareness Algorithm Development.Ph. D.
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Åfeldt, Tom. "Adaptive Steering Behaviour for Heavy Duty Vehicles." Thesis, KTH, Reglerteknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-215134.
Abstract:
Today the majority of the driver assistance systems are rule-basedcontrol systems that help the driver control the truck. But driversare looking for something more personal and exible that can controlthe truck in a human way with their own preferences. Machine learningand articial intelligence can help achieve this aim. In this studyArticial Neural Networks are used to model the driver steering behaviourin the Scania Lane Keeping Assist. Based on this, trajectoryplanning and steering wheel torque response are modelled to t thedriver preference. A model predictive controller can be used to maintainstate limitations and to weigh the two modelled driver preferencestogether. Due to the diculties in obtaining an internal plant modelfor the model predictive controller a variant of a PI-controller is addedfor integral action instead. The articial neural network also containsan online learning feature to further customize the t to the driverpreference over time.Idag används till största del regelbaserade reglersystem förförarassistanssystem i lastbilar. Men lastbilschaufförer vill ha någotmer personligt och flexibelt, som kan styra lastbilen på ett mänskligtsätt med förarens egna preferenser. Maskininlärning och artificiell intelligenskan hjälpa till för att uppnå detta mål. I denna studie användsartificiella neurala nätverk för att modellera förarens styrbeteende genomScania Lane Keeping Assist. Med användning av detta modellerasförarens preferenser med avseende på placering på vägbanan och momentpåslag på ratten. En modell prediktiv kontroller kan användas föratt begränsa tillstånd och för att väga de två modellerade preferensernamot varann. Eftersom det var mycket svårt att ta fram den internaprocessmodellen som krävdes för regulatorn används istället en variantav en PI-kontroller för att styra lastbilen. De artificiella neuralanätverken kan också tillåtas att lära sig under körning för att anpassasig till förarens preferenser över tid.
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Lemonnier, Louis. "The Semantics of Effects : Centrality, Quantum Control and Reversible Recursion." Electronic Thesis or Diss., université Paris-Saclay, 2024. http://www.theses.fr/2024UPASG030.
Abstract:
Le sujet de cette thèse est axé sur la théorie des langages de programmation. Dans un langage de programmation suffisamment bien défini, le comportement des programmes peut être étudié à l'aide d'outils empruntés à la logique et aux mathématiques, énonçant des résultats sans exécuter le code. Ce domaine de l'informatique est appelé "sémantique". La sémantique d'un langage peut se présenter sous plusieurs formes : dans notre cas, des sémantiques opérationnelles, des théories équationnelles et des sémantiques dénotationnelles. Les premières donnent un sens opérationnel aux programmes, au sein de la syntaxe du langage. Elles simulent les opérations qu'un ordinateur est censé effectuer s'il exécute le programme. Une théorie équationnelle fonctionne également de manière syntaxique : elle indique si deux programmes effectuent la même opération sans informer sur la procédure. Enfin, la sémantique dénotationnelle est l'étude mathématique des programmes, généralement à l'aide de la théorie des catégories. Elle permet par exemple de prouver qu'un programme se termine ou non. Cette thèse se concentre sur la sémantique des effets dans les langages de programmation - une fonctionnalité ajoutée à un langage, gérant des données secondaires ou des résultats probabilistes. Eugenio Moggi, en 1991, a publié un travail fondateur sur l'étude de la sémantique des effets, soulignant la relation avec les monades en théorie des catégories. La première contribution de cette thèse suit directement le travail de Moggi, en étudiant la commutativité des effets dans un langage de programmation à travers le prisme des monades. Les monades sont la généralisation de structures algébriques telles que les monoïdes, qui ont une notion de centre : le centre d'un monoïde est une collection d'éléments qui commutent avec tous les autres dans le monoïde. Nous fournissons les conditions nécessaires et suffisantes pour qu'une monade ait un centre. Nous détaillons également la sémantique d'un langage de programmation avec des effets qui portent des informations sur les effets qui sont centraux. De plus, nous fournissons un lien fort - un résultat de langage interne - entre ses théories équationnelles et sa sémantique dénotationnelle. Le deuxième axe de la thèse est l'informatique quantique, perçue comme un effet réversible. Le quantique est un domaine émergent de l'informatique qui utilise la puissance de la mécanique quantique pour calculer. Au niveau des langages de programmation, de nouveaux paradigmes doivent être développés pour être fidèles aux opérations quantiques. Les opérations quantiques physiquement permises sont toutes réversibles, à l'exception de la mesure ; cependant, la mesure peut être reportée à la fin du calcul, ce qui nous permet de nous concentrer d'abord sur la partie réversible et d'appliquer ensuite la mesure pour obtenir des résultats. Dans le chapitre correspondant, nous définissons un langage de programmation réversible, avec types simples, qui effectue des opérations quantiques "unitaires". Une sémantique dénotationnelle et une théorie équationnelle adaptées au langage sont présentées, et nous prouvons que cette dernière est complète. Ce travail vise à fournir des bases solides pour l'étude du contrôle quantique d'ordre supérieur. En outre, nous étudions la récursion réversible, en fournissant une sémantique opérationnelle et dénotationnelle adéquate à un langage de programmation fonctionnel, réversible et Turing-complet. La sémantique dénotationnelle utilise l'enrichissement dcpo des catégories inverses. Ce modèle mathématique sur l'informatique réversible ne se généralise pas directement à sa version quantique. Dans la conclusion, nous détaillons les limites et l'avenir possible du contrôle quantique d'ordre supérieurThe topic of this thesis revolves around the theory of programming languages. In a sufficiently well-defined programming language, the behaviour of programs can be studied with tools borrowed from logic and mathematics, allowing us to state results without executing the code. This area of computer science is called “semantics”. The semantics of a programming language can take several forms: in this thesis, we work with operational semantics, equational theories, and denotational semantics. The former gives an operational meaning to programs but within the language's syntax. It simulates the operations a computer is supposed to perform if it were running the program. An equational theory also works syntactically: it indicates whether two programs perform the same operation without giving any information on the procedure. Lastly, denotational semantics is the mathematical study of programs, usually done with the help of category theory. For example, it allows us to prove whether a program terminates. This thesis focuses on the semantics of effects in programming languages - namely, a feature added to a language, e.g. handling side data or probabilistic outputs. Eugenio Moggi, in 1991, published foundational work on the study of the semantics of effects, highlighting the relationship with monads in category theory. The first contribution of this thesis directly follows Moggi's work, studying the commutativity of effects in a programming language through the prism of monads. Monads are the generalisation of algebraic structures such as monoids, which have a notion of centre: the centre of a monoid is a collection of elements which commute with all others in the monoid. We provide the necessary and sufficient conditions for a monad to have a centre. We also detail the semantics of a programming language with effects that carry information on which effects are central. Moreover, we provide a strong link - an internal language result - between its equational theories and its denotational semantics. The second focus of the thesis is quantum computing, which is seen as a reversible effect. Quantum computing is an emergent field in computer science that uses the power of quantum mechanics to compute. At the level of programming languages, new paradigms need to be developed to be faithful to quantum operations. Physically permissible quantum operations are all reversible, except measurement; however, measurement can be deferred at the end of the computation, allowing us to focus on the reversible part first and then apply measurement to obtain results. In the corresponding chapter, we define a simply-typed reversible programming language performing quantum operations called “unitaries”. A denotational semantics and an equational theory adapted to the language are presented, and we prove that the latter is complete. The aim of this work is to provide a solid foundation for the study of higher-order quantum control. Furthermore, we study recursion in reversible programming, providing adequate operational and denotational semantics to a Turing-complete, reversible, functional programming language. The denotational semantics uses the dcpo enrichment of rig join inverse categories. This mathematical account of higher-order reasoning on reversible computing does not directly generalise to its quantum counterpart. In the conclusion, we detail the limitations and possible future for higher-order quantum control
49
Cembalo, Agostino. "Stratégie innovante d'optimisation de la traînée aérodynamique en temps réel pour l'amélioration de l'efficacité énergétique des voitures." Electronic Thesis or Diss., Chasseneuil-du-Poitou, Ecole nationale supérieure de mécanique et d'aérotechnique, 2024. http://www.theses.fr/2024ESMA0007.
Abstract:
La réduction des émissions de CO2 et de l’empreinte environnementale représente un défi majeur pour l’industrie automobile au XXIe siècle, avec environ 72% des émissions de gaz à effet de serre dans le secteur des transports européens attribuées au transport routier. Pour répondre à cette problématique, les constructeurs automobiles mettent de plus en plus l’accent sur la réduction de l'empreinte environnementale de leurs véhicules ainsi que sur la minimisation de la consommation d'énergie. Dans cette optique, l'aérodynamique des voitures joue un rôle crucial. Cette étude explore donc les défis et opportunités associés au contrôle en temps réel du sillage des véhicules en utilisant une commande prédictive avec une estimation récursive du modèle basée sur la méthode des sous-espaces (RSPC). Nous caractérisons tout d'abord le sillage d’une voiture en pleine échelle, à la fois en soufflerie et sur route. Les résultats soulignent l'importance des phénomènes à basse fréquence et des mouvements quasi-statiques du sillage. Ensuite, nous mettons en œuvre une méthodologie de contrôle visant à réguler les positions angulaires de volets rigides situés au culot des modèles étudiés afin de maintenir un état de pression imposé au culot. Parmi les résultats significatifs, nous notons que la loi de commande parvient à atteindre les objectifs définis dans des conditions variées, y compris face à des variations d'angle de dérapage et des perturbations de l'écoulement de soubassement grâce à l'utilisation d'une grille mobile placée en amont du véhicule. Les bénéfices observés en termes de traînée aérodynamique sont remarquables et dépendent du modèle étudié, tout en maintenant une consommation énergétique relativement faible. En effet, la consommation énergétique du système varie entre 0.35% et 0.6% de la puissance aérodynamique dissipée. En conclusion, cette étude ouvre de nouvelles perspectives pour le contrôle aérodynamique des véhicules, offrant des opportunités significatives de réduction de la consommation d'énergie et, par conséquent, des émissions de gaz à effet de serre. Elle essaye ainsi de contribuer à atténuer les effets du changement climatiqueThe reduction of CO2 emissions and environmental footprint represents a major challenge for the automotive industry in the 21st century, with approximately 72% of greenhouse gas emissions in the European transportation sector attributed to road transport. To address this issue, automotive manufacturers are increasingly focusing on reducing the environmental footprint of their vehicles and minimizing energy consumption. In this context, car aerodynamics plays a crucial role. This study therefore explores the challenges and opportunities associated with real-time control of vehicle’s wakes using a Predictive Control with Recursive model estimation based on a Subspace method (RSPC). We first characterize the wake of a full-scale vehicle, both in wind tunnel and on-road. The results highlight the importance of low-frequency phenomenons and quasi-static wake movements. Subsequently, we implement a control methodology aimed at regulating the angular positions of rigid flaps located at the base of the studied models to maintain a prescribed base pressure state. Among the significant results, we note that the control law succeeds in achieving defined objectives under varied conditions, including variations in yaw angle and disturbances in the underflow through the use of a movable grid placed upstream of the vehicle. The observed benefits in terms of aerodynamic drag are remarkable and model-dependent, while maintaining relatively low energy consumption. The latter varies between 0.35% and 0.6% of the dissipated aerodynamic power. In conclusion,this study opens new perspectives for vehicle aerodynamic control, offering significant opportunities for energy consumption reduction and, consequently, greenhouse gas emissions. It thus aim to mitigating the effects of climate change
50
Ortega, Felix Mauricio Escalante. "Filtragem e controle recursivos robustos aplicados em um pêndulo invertido." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/18/18153/tde-15092016-075814/.
Abstract:
O estudo da estabilidade e desempenho em sistemas de controle é um tópico relevante na teoria de sistemas. Quando são assumidas incertezas no modelo da planta, existe uma maior dificuldade para garantir um nível de desempenho adequado do sistema dinâmico e a estabilidade pode ser comprometida. Neste trabalho são utilizados um regulador linear quadrático robusto e um filtro de Kalman robusto combinados em uma única formulação para tratar de sistemas dinâmicos incertos em tempo real. O caso de estudo selecionado é o pêndulo invertido. Seus principais desafios de controle encontrados na literatura: estabilização, seguimento e levantamento-captura, serão considerados. Os algoritmos utilizados são motivados pelo fato de que problemas estocásticos podem ser resolvidos por meio de argumentos determinísticos, baseados nos conceitos de função penalidade e mínimos quadrados regularizados. Desta forma, é possível a obtenção do melhor desempenho em contrapartida à máxima influência de incerteza admissível. A análise de desempenho do controlador robusto é realizada por meio de ensaios práticos incluindo incertezas na planta, ruído nos sensores e distúrbios no sinal de controle do pêndulo.The study of stability and performance in control systems is a relevant topic in systems theory. When uncertainties are considered in the model of the plant, there is a greater difficulty in ensuring an appropriate performance level of the dynamic system, plus, the stability could be compromised as well. In this dissertation a robust linear quadratic regulator and a robust Kalman filter are used in a unified manner to deal with uncertain dynamic systems in real time. The selected case study is the inverted pendulum. Its main control challenges found in the literature will be considered: stabilization, tracking and catching swing-up. The used algorithms are motivated by the fact that stochastic problems can be solved through deterministic arguments based on the concepts of penalty function and regularized least-squares. Thus, it is possible to obtain an optimal performance for the maximum acceptable uncertainty. The performance analysis of the robust control is carried out by practical experiments including uncertainties in the plant, noise in the sensors and disturbance in the pendulum control signal.