Dissertations / Theses on the topic 'Control system coordination'

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1

Kibushi, Benio. "Muscle and kinematic coordination system in human walking." Kyoto University, 2019. http://hdl.handle.net/2433/242738.

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Kyoto University (京都大学)
0048
新制・課程博士
博士(人間・環境学)
甲第21861号
人博第890号
新制||人||213(附属図書館)
2018||人博||890(吉田南総合図書館)
京都大学大学院人間・環境学研究科共生人間学専攻
(主査)教授 神﨑 素樹, 教授 石原 昭彦, 教授 久代 恵介
学位規則第4条第1項該当
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2

Nguyen, Van Liem. "Modeling and control coordination of power systems with FACTS devices in steady-state operating mode." University of Western Australia. School of Electrical, Electronic and Computer Engineering, 2008. http://theses.library.uwa.edu.au/adt-WU2009.0036.

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This thesis is devoted to the development of new models for a recently-implemented FACTS (flexible alternating current transmission system) device, the unified power flow controller (UPFC), and the control coordination of power systems with FACTS devices in steady-state operating mode. The key objectives of the research reported in the thesis are, through online control coordination based on the models of power systems having FACTS devices, those of maximising the network operational benefit and restoring system static security following a disturbance or contingency. Based on the novel concept of interpreting the updated voltage solutions at each iteration in the Newton-Raphson (NR) power-flow analysis as dynamic variables, the thesis first develops a procedure for representing the unified power flow controllers (UPFCs) in the steady-state evaluation. Both the shunt converter and series converter control systems of a UPFC are modeled in their dynamical form with the discrete time variable replaced by the NR iterative step in the power-flow analysis. The key advantage of the model developed is that of facilitating the process of UPFC constraint resolution during the NR solution sequence. Any relative priority in control functions pre-set in the UPFC controllers is automatically represented in the power-flow formulation. Although the developed UPFC model based on the dynamic simulation of series and shunt converter controllers is flexible and general, the number of NR iterations required for convergence can be large. Therefore, the model is suitable mainly for power system planning and design studies. For online control coordination, the thesis develops the second UPFC model based on nodal voltages. The model retains all of the flexibility and generality of the dynamic simulation-based approach while the number of iterations required for solution convergence is independent of the UPFC controller dynamic responses. Drawing on the constrained optimisation based on Newton’s method together with the new UPFC model expressed in terms of nodal voltages, a systematic and general method for determining optimal reference inputs to UPFCs in steady-state operation is developed. The method is directly applicable to UPFCs operation with a high-level line optimisation control (LOC) for maximising the network operational benefit. By using a new continuation technique with adaptive parameter, the algorithm for solving the constrained optimisation problem extends substantially the region of convergence achieved with the conventional Newton’s method. Having established the foundation provided by the comprehensive models developed for representing power systems with FACTS devices including the UPFC, the research, in the second part, focuses on real-time control coordination of power system controllers, with the main purpose of restoring power system static security following a disturbance or contingency. At present, as the cost of phasor measurement units (PMUs) and wide-area communication network is on the decrease, the research proposes and develops a new secondary voltage control where voltages at all of the load nodes are directly controlled, using measured voltages.
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Gianto, Rudy. "Coordination of power system controllers for optimal damping of electromechanical oscillations." University of Western Australia. School of Electrical, Electronic and Computer Engineering, 2008. http://theses.library.uwa.edu.au/adt-WU2009.0056.

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This thesis is devoted to the development of new approaches for control coordination of PSSs (power system stabilisers) and FACTS (flexible alternating current transmission system) devices for achieving and enhancing small-disturbance stability in multi-machine power systems. The key objectives of the research reported in the thesis are, through optimal control coordination of PSSs and/or FACTS devices, those of maintaining satisfactory power oscillation damping and secure system operation when the power system is subject to persisting disturbances in the form of load demand fluctuations and switching control. Although occurring less frequently, fault disturbances are also considered in the assessment of the control coordination performance. Based on the constrained optimisation method in which the eigenvalue-based objective function is minimised to identify the optimal parameters of power system damping controllers, the thesis first develops a procedure for designing the control coordination of PSSs and FACTS devices controllers. The eigenvalue-eigenvector equations associated with the selected electromechanical modes form a set of equality constraints in the optimisation. The key advance of the procedure is that there is no need for any special software system for eigenvalue calculations, and the use of sparse Jacobian matrix for forming the eigenvalue-eigenvector equations leads to the sparsity formulation which is essential for large power systems. Inequality constraints include those for imposing bounds on the controller parameters. Constraints which guarantee that the modes are distinct ones are derived and incorporated in the control coordination formulation, using the property that eigenvectors associated with distinct modes are linearly independent. The robustness of the controllers is achieved very directly through extending the sets of equality constraints and inequality constraints in relation to selected eigenvalues and eigenvectors associated with the state matrices of power systems with loading conditions and/or network configurations different from that of the base case. On recognising that the fixed-parameter controllers, even when designed with optimal control coordination, have an inherent limitation which precludes optimal system damping for each and every possible system operating condition, the second part of ii the research has a focus on adaptive control techniques and their applications to power system controllers. In this context, the thesis reports the development of a new design procedure for online control coordination which leads to adaptive PSSs and/or supplementary damping controllers (SDCs) of FACTS devices for enhancing the stability of the electromechanical modes in a multi-machine power system. The controller parameters are adaptive to the changes in system operating condition and/or configuration. Central to the design is the use of a neural network synthesised to give in its output layer the optimal controller parameters adaptive to system operating condition and configuration. A novel feature of the neural adaptive controller is that of representing the system configuration by a reduced nodal impedance matrix which is input to the neural network.
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4

Culioli, Jean-Christophe. "Algorithmes de decomposition/coordination en optimisation stochastique." Paris, ENMP, 1987. http://www.theses.fr/1987ENMP0059.

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Les systemes consideres, souvent complexes a modeliser et/ou optimiser peuvent etre constitues de sous-systemes heterogenes pour lesquels une technique globale de resolution n'est pas necessairement appropriee ou possible, meme s'ils sont equivalents et peu nombreux
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5

Reynolds, Hayley J. Davison (Hayley Jaye Davison). "Identification of communication and coordination issues in the U.S. air traffic control system." Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/81565.

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6

Slay, Tylor. "Adoption of an Internet of Things Framework for Distributed Energy Resource Coordination and Control." PDXScholar, 2018. https://pdxscholar.library.pdx.edu/open_access_etds/4464.

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Increasing penetration of non-dispatchable renewable energy resources and greater peak power demand present growing challenges to Bulk Power System (BPS) reliability and resilience. This research investigates the use of an Internet of Things (IoT) framework for large scale Distributed Energy Resource (DER) aggregation and control to reduce energy imbalance caused by stochastic renewable generation. The aggregator developed for this research is Distributed Energy Resource Aggregation System (DERAS). DERAS comprises two AllJoyn applications written in C++. The first application is the Energy Management System (EMS), which aggregates, emulates, and controls connected DERs. The second application is the Distributed Management System (DMS), which is the interface between AllJoyn and the physical DER. The EMS runs on a cloud-based server with an allocated 8 GB of memory and an 8 thread, 2 GHz processor. Raspberry Pis host the simulated Battery Energy Storage System (BESS) or electric water heater (EWH) DMSs. Five Raspberry Pis were used to simulate 250 DMSs. The EMS used PJM's regulation control signals, RegA and RegD, to determine DERAS performance metrics. PJM is a regional transmission organization (RTO). Their regulation control signals direct power resources to negate load and generation imbalances within the BPS. DERAS's performance was measured by the EMS server resource usage, network data transfer, and signal delay. The regulation capability of aggregated DER was measured using PJM's resource performance assessment criteria. We found the use of an IoT framework for DER aggregation and control to be inadequate in the current network implementation. However, the emulated modes and aggregation response to the regulated control signal demonstrates an excellent opportunity for DER to benefit the BPS.
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7

Pourbeik, Pouyan. "Design and coordination of stabilisers for generators and FACTS devices in multimachine power systems /." Title page, contents and abstract only, 1997. http://web4.library.adelaide.edu.au/theses/09PH/09php877.pdf.

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8

Marín, Collazos Luis Gabriel. "Hierarchical energy management system based on fuzzy prediction intervals for operation and coordination of microgrids." Tesis, Universidad de Chile, 2018. http://repositorio.uchile.cl/handle/2250/170000.

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Tesis para optar al grado de Doctor en Ingeniería Eléctrica
The integration of large numbers of Distributed Energy Resources (DERs) into the distribution system could take place either by reinforcement of the existing network assets, or the incorporation of active management of flexible resources into different sections of the distribution network. For active management of a distribution network, the design of control strategies is necessary for an efficient and reliable large-scale integration of DERs. Besides the benefit of supporting the use of renewable energy sources, DERs play an important role in improving the resilience and sustainability of the electricity distribution system and also in the generation of new market opportunities. In this thesis, the active management of DERs is proposed using a hierarchical energy management system (EMS) applied to "Energy Communities". Energy communities are a concept which allows different end users to cooperate in their energy interactions with the aim of maximising their self-consumption, minimising energy costs, reducing peak power levels or a combination of these and other beneficial goals as well. The hierarchical EMS proposed allows incorporating mechanisms to ensure both the realisation of short-term power balancing objectives and long-term energy management, benefiting the microgrid owner and the distribution network operator. The hierarchical EMS is designed in two levels: main grid level and microgrid level. At the microgrid level, a real-time local rule-based controller is proposed and at the higher level, a Robust model predictive control (MPC) is used to manage the uncertainty associated with renewable distributed generation and electricity demand. The uncertainty is incorporated into the Robust MPC controller based on fuzzy prediction interval models in order to help the system to be prepared for errors in the predictions that might yield sub-optimal decisions. Several case studies are used to test the performance of the hierarchical EMS for the operation and coordination of microgrids. Robust EMS based on fuzzy prediction interval models is compared to the deterministic EMS and with a basic EMS without energy storage system (ESS). The results show that the deterministic and Robust EMSs provide improvements over the case without ESS, as they offer mechanisms for efficient energy management. The incorporation of an ESS into the energy community benefits both the end user, by reducing energy cost, and the distribution network operator, by limiting the peak power levels and enabling increased penetration of distributed generation (DG). Additionally, the hierarchical EMS is able to keep the community power flow close to the reference power defined by the higher level controller with minimum energy cost, among other benefits. Finally, end users operating as Energy Communities can optimise the use of DG and the size of the ESS required.
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9

Sarasua, Wayne Alexander. "SIG-GIS : a GIS based traffic signal coordination and information management system." Diss., Georgia Institute of Technology, 1992. http://hdl.handle.net/1853/19085.

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10

Collins, Mark. "Multi-agent system control and coordination of distributed energy resources in electrical power networks." Thesis, Imperial College London, 2013. http://hdl.handle.net/10044/1/24735.

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The central question to be addressed in this thesis is whether Active Network Management (ANM) implemented through a Multi-Agent System (MAS) can offer a realistic basis for managing a distribution network of the future. These networks will contain many more Distributed Energy Resources (DER) than present networks resulting in a more regular occurrence of constraints being violated because of the network's increased usage. A review of ANM schemes is presented in order to show their impact on the global and local operation of distribution networks, the economic impacts and benefits they have, and the limitations that arise from the centralisation of operations. This thesis shows that a distributed MAS implementation of ANM could potentially remove limitations associated with a centralised approach to ANM. However, present MAS ANM approaches raise concerns with regards to their operation on realistic networks, the communication burden they create, the safety and security of their operation and the economic considerations taken when implementing decisions. This thesis proposes a MAS ANM scheme with an agent allocated to every node of the network, implementing a fully decentralised decision making algorithm. These agents are all peers and use message propagation so voltage approximations can be calculated and DER corrective actions shared without the need for a complete, central network model to exist. Agents select a beneficial control action to satisfy voltage constraints in order to minimise corrective costs associated with the DER actions. This is achieved by combining the cost of various DER corrective actions and a cost allocated to voltage excursions outside the target control range. This approach removes the need for a central moderator, avoiding potential single point failures and reducing communication overheads of present MAS ANM schemes. Furthermore to ensure this MAS ANM does not affect the present GB energy market operation, the cost associated with DER corrective actions reflects the real revenue incurred by DER owners and compensated by the MAS ANM scheme operator. Finally to confirm that the MAS ANM meets the main aim of the thesis, it is shown to successfully operate upon many test distribution network configurations, rapidly bring voltage excursions from load changes back within limits. The solutions found are comparable to an Optimal Power Flow (OPF) supplied with a full network model and set of DER costs, confirming its ability to provide similar results to centralised ANM schemes with the benefits over the operational limitations of proposed centrally moderated MAS ANM schemes.
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11

Sharman, Kimberly. "A broadcast-based coordination scheme for a system of autonomous mobile robots." Thesis, Virginia Tech, 1994. http://hdl.handle.net/10919/42057.

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A method for coordinating a homogeneous swarm of autonomous mobile robots is presented. The broadcast-based coordination scheme was developed for the Army Ant swarm—a system of small, relatively inexpensive mobile robots that can accomplish complex tasks by cooperating as a team. The primary drawback of the Army Ant system is that the absence of a central supervisor poses difficulty in the coordination and control of the agents. Our coordination scheme provides a global "group dynamic" that controls the actions of each robot using only local interactions. Coordination of the swarm is achieved with signals we call "heartbeats". Each agent broadcasts a unique heartbeat and responds to the collective behavior of all other heartbeats. We generate heartbeats with van der Pol oscillators, which are nonlinear oscillators that modify their output when coupled to other oscillators. Van der Pol oscillators have long been utilized in simulations, particularly to model rhythmic behavior in biological systems. In this application, we use the known properties of coupled van der Pol oscillators to create predictable group behavior. We emphasize the use of this controller to allow agents to simultaneously perform an action such as lifting, steering, or changing speed. For this research we synthesize a three oscillator network to show that we can achieve multi-agent coordination. An inexpensive FM communication link is used to broadcast and receive oscillator signals. We show that the network may be configured to entrain to a leader or to a common frequency. Additionally, we use our coordination scheme to provide global speed control to our three agent system.
Master of Science
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12

DOTTOR, ALBERTO. "MOTOR CONTROL OF THUMB-INDEX SYSTEM IN HEALTHY POPULATION." Doctoral thesis, Università degli studi di Genova, 2021. http://hdl.handle.net/11567/1057767.

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Thumb and Index fingers are involved in many daily tasks, it is understandable how injuries, musculoskeletal, rheumatologic, and neurological diseases could affect hand function causing severe disability. The evaluation of motor control deficits of the thumb-index system is necessary to identify impairments and to propose specific therapeutic or surgical proposes. Pinch maximal voluntary contraction is the most investigated parameter, it is a valid estimator of general hand function. However, thumb and index are rarely involved at their maximal contraction, usually they are used in precision pinches at low submaximal forces exerted for a short-to-long time. For this reason other parameters must be investigated. In this dissertation, a multiparametric evaluation of thumb-index system was proposed. The battery of tests consisted of the maximal voluntary contraction (MVC) of pinch grip (TP, tip pinch and PP, palmar pinch) and of the opposite movement (E, extension of thumb and index), the endurance (SC, sustained contraction), the accuracy and precision of pinch force in a pinch and release task (DC, dynamic contraction) and the force coordination between hands in a bimanual simultaneous task (BSC, bimanual strength coordination). The tasks were measured with a measurement system consisted of two pinch gauges, connected to a PC, the visual feedback was displayed on a monitor through the graphical user interface of an ad-hoc developed software. To be usable in the clinical context, it is important to check the reliability of the tasks and collecting data in healthy samples permits on the one hand to analyse how values changes as function of anthropometric variables, hand dominance, dexterity, and on the other hand to define the reference values to compare pathological populations. Therefore this dissertation was conducted through test-retest reliability studies and cross-sectional studies to establish normative data of PP, TP, E MVCs, SC, DC and BSC in the Italian population. All the tasks proved reliable and consistent, MVC and SC showed high reliability, DC and BSC reliability was lower but clinically suitable. Strength, analysed through PP, TP, E MVCs, declined in line with the normal process of aging that also entails muscle fibers and the reduction of daily activities in older adults. In relative terms, E-MVC showed the highest strength loss in the over 75y. SC showed similar values in all age groups, variables of DC and BSC showed instead large effect related to age-decline. Women performed better than men only in SC, in MVC, DC and BSC men excelled. A hand dominance effect emerged only in TP and PP MVC. Correlations between tasks were very low to low, suggesting that different constructs were measured by the tasks. This Ph.D. project proposed novel tasks to evaluate pinch motor control which were showed reliable in healthy people and their normative data were obtained, representing a useful aid in the clinical field. The results become a starting point for future studies to highlight impairments of the thumb-index system in different neurological and musculoskeletal disorders and to guide the rehabilitation and the therapeutic intervention.
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Herrera, Santisbon Eunice. "Production-consumption system coordination by hybrid predictive approaches : application to a solar cooling system for buildings." Thesis, CentraleSupélec, 2015. http://www.theses.fr/2015SUPL0006/document.

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Garantir le confort thermique des bâtiments est directement lié à la consommation d'énergie. Dans les zones tropicales, les systèmes de refroidissement représentent l'un des postes les plus gourmands en énergie. Afin de réduire la consommation d'énergie mondiale, il est primordial d'améliorer l'efficacité de ces systèmes ou bien de développer de nouvelles méthodes de production de froid. Une installation de refroidissement solaire basé sur le cycle à absorption est une alternative pour réduire les émissions de gaz à effet de serre et la consommation d'électricité. Contrairement aux systèmes classiques de refroidissement à compression mécanique, la production de froid par absorption est un système complexe composé de plusieurs composants comme des panneaux solaires, un ballon de stockage, une tour de refroidissement et une machine à absorption. Outre le dimensionnement des composants, ce système complexe nécessite des actions de contrôle pour être efficace parce que la coordination entre le stockage d'eau chaude, la production et la consommation du froid est nécessaire. Le but de cette thèse est de proposer une structure producteur-consommateur d'énergie basée sur la commande prédictive (MPC). Le système de refroidissement par absorption solaire est considéré comme faisant partie de ce système de production-consommation d'énergie, le système de stockage d'eau chaude est le producteur et la machine à absorption qui distribue de l'eau froide au bâtiment est l'un des consommateurs. Pour que la structure de commande soit modulaire, la coordination entre les sous-systèmes est réalisée en utilisant une approche de partitionnement où des contrôleurs prédictifs locaux sont conçus pour chacun des sous-systèmes. Les contrôleurs des consommateurs calculent un ensemble de profils de demande d'énergie. Ces profils sont ensuite envoyés au contrôleur du producteur qui sélectionne le profil qui minimise le coût global. Dans une première partie, l'approche proposée est testée sur un modèle linéaire simplifié composé d'un producteur et plusieurs consommateurs. Dans une deuxième partie, un cas plus complexe est étudié. Un modèle simplifié d'un système de refroidissement à absorption est évaluée en utilisant l'outil de simulation TRNSYS. Le modèle de production n'est plus linéaire, il est décrit par un modèle non linéaire hybride qui augmente la complexité du problème d'optimisation. Les résultats des simulations montrent que la sous-optimalité induite par la méthode est faible. De plus, la performance de l'approche atteint les objectifs de commande tout en respectant les contraintes
To guarantee thermal comfort in buildings is directly related to energy consumption. In tropical climates, cooling systems for buildings represent one of the largest energy consumers. Therefore, as energy consumption is a major concern around the world, it is important to improve the systems efficiency or seeking new methods of cooling production. A solar cooling installation based on the absorption cycle is an alternative to mitigate greenhouse gas emissions and electricity consumption. In contrast to conventional vapor-compression based cooling systems, the absorption cooling production involves a complex system composed of several components as collector panel, storage tank, cooling tower and absorption chiller. Besides the sizing of the components, this complex system requires control actions to be efficient as a coordination between hot water storage, cooling water production and consumption is necessary. The aim of this research is to propose a management approach for a production-consumption energy system based on Model Predictive Control (MPC). The solar absorption cooling system is seen as part of this production-consumption energy system where the hot water storage system is the producer and the chiller-building system is one of the consumers. In order to provide modularity to the control structure, the coordination between the subsystems is achieved by using a partitioning approach where local predictive controllers are developed for each of the subsystems. The consumer controllers compute a set of energy demand profiles sent to the producer controller which selects the profile that better minimize the global optimization cost. In a first part, the proposed approach is tested on a simplified linear model composed of one producer and several consumers. In a second part, a more complex case is studied. A simplified model of an absorption cooling system is evaluated using the simulation tool TRNSYS. The producer model is no longer linear, instead it is described by a nonlinear hybrid model which increases the complexity of the optimization problem. The simulations results show that the suboptimality induced by the method is low and the control strategy fulfills the objectives and constraints while giving good performances
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Maurer, Simon. "Analysis and coordination of mixed-criticality cyber-physical systems." Thesis, University of Hertfordshire, 2018. http://hdl.handle.net/2299/21094.

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A Cyber-physical System (CPS) can be described as a network of interlinked, concurrent computational components that interact with the physical world. Such a system is usually of reactive nature and must satisfy strict timing requirements to guarantee a correct behaviour. The components can be of mixed-criticality which implies different progress models and communication models, depending whether the focus of a component lies on predictability or resource efficiency. In this dissertation I present a novel approach that bridges the gap between stream processing models and Labelled Transition Systems (LTSs). The former offer powerful tools to describe concurrent systems of, usually simple, components while the latter allow to describe complex, reactive, components and their mutual interaction. In order to achieve the bridge between the two domains I introduce the novel LTS Synchronous Interface Automaton (SIA) that allows to model the interaction protocol of a process via its interface and to incrementally compose simple processes into more complex ones while preserving the system properties. Exploiting these properties I introduce an analysis to identify permanent blocking situations in a network of composed processes. SIAs are wrapped by the novel component-based coordination model Process Network with Synchronous Communication (PNSC) that allows to describe a network of concurrent processes where multiple communication models and the co-existence and interaction of heterogeneous processes is supported due to well defined interfaces. The work presented in this dissertation follows a holistic approach which spans from the theory of the underlying model to an instantiation of the model as a novel coordination language, called Streamix. The language uses network operators to compose networks of concurrent processes in a structured and hierarchical way. The work is validated by a prototype implementation of a compiler and a Run-time System (RTS) that allows to compile a Streamix program and execute it on a platform with support for ISO C, POSIX threads, and a Linux operating system.
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Phulpin, Yannick Dominique. "Coordination of reactive power scheduling in a multi-area power system operated by independent utilities." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/31638.

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Thesis (Ph.D)--Electrical and Computer Engineering, Georgia Institute of Technology, 2010.
Committee Chair: Begovic, Miroslav; Committee Member: Divan, Deepak; Committee Member: Harley, Ron; Committee Member: Petit, Marc; Committee Member: Verriest, Erik. Part of the SMARTech Electronic Thesis and Dissertation Collection.
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Patel, Raj Haresh. "Autonomous cars' coordination among legacy vehicles applied to safe braking." Electronic Thesis or Diss., Sorbonne université, 2018. http://www.theses.fr/2018SORUS468.

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Le comportement d'un véhicule autonome peut être affecté par divers facteurs internes tels que défaillance du système de bord, capteur, etc., ou par des facteurs externes tels que manœuvres risquées de la part de voisins immédiats menaçant une collision, des changements brusques de l'état des routes, etc. Cela peut entraîner une défaillance de la manœuvre de coordination, telle que le croisement de plusieurs véhicules à une intersection. Dans de telles situations, lorsque les conditions changent de manière dynamique et que la condition de fonctionnement nominale est violée par des influences internes ou externes, un véhicule autonome doit avoir la capacité d'atteindre la condition de risque minimal. Arrêter le véhicule est l’un des moyens d’atteindre un niveau de risque minimal. La thèse introduit un algorithme d'arrêt sécurisé qui génère des commandes pour véhicules autonomes en tenant compte de la présence de véhicules traditionnels. Un algorithme basé sur un modèle de contrôle prédictif est proposé, qui résiste aux erreurs provenant de la communication, la localisation, la mise en œuvre du contrôle et à la disparité des modèles. Les collisions évitées et la gêne ressentie par le conducteur sont deux paramètres d'évaluation. Les simulations montrent que le contrôleur robuste sous l'influence d'erreurs peut fonctionner aussi bien que le contrôleur non-robuste en l'absence d'erreurs
The behaviour of an autonomous vehicle can be impacted by various internal factors like onboard system failure, sensor failure, etc. or by external factors like risky maneuvers by immediate neighbors threatening a collision, sudden change in road conditions, etc. This can result in a failure of coordination maneuver like multi-vehicle intersection clearance. In such situations when conditions dynamically change and the nominal operational condition is violated by internal or external influences, an autonomous vehicle must have the capability to reach the minimal risk condition. Bringing the vehicle to a halt is one of the ways to achieve minimal risk condition. This thesis introduces a safe stop algorithm which generates controls for multiple autonomous vehicles considering the presence of legacy manually driven vehicles on the road. A Model Predictive Control based algorithm is proposed which is robust to errors in communication, localization, control implementation, and model mismatch. Collisions avoided and discomfort faced by the driver are two evaluation parameters. Simulations show that the robust controller under the influence of errors can perform as well as the non-robust controller in the absence of these errors
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Sun, Jisang. "Human Interfaces for Cooperative Control of Multiple Vehicle Systems." Diss., CLICK HERE for online access, 2006. http://contentdm.lib.byu.edu/ETD/image/etd1230.pdf.

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Wei, Jin. "Modeling and Coordination of interconnected microgrids using distributed artificial intelligence approaches." Thesis, Bourgogne Franche-Comté, 2019. http://www.theses.fr/2019UBFCA021.

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À mesure que les sources renouvelables pénètrent dans le système électrique actuel pour atténuer le réchauffement planétaire et la pénurie d’énergie, le concept de microréseau (MG) permet de réduire l’impact de la production intermittente sur le réseau de services publics. Il permet d'améliorer l’automatisation et l’intelligence du réseau électrique avec des caractéristiques plug-and-play. L’intégration d’un plus grand nombre de MG dans un réseau de distribution favorise le développement du réseau intelligent. Leur coordination pourrait conduire à une grande fiabilité du système avec un faible coût, et une forte résistance aux pannes électriques. La réalisation de ces profits repose sur des technologies développées de communication et de stratégies de contrôle.La répartition de la puissance dans les MG répartis tout en coordonnant les éléments au sein de chaque MG exige un contrôle décentralisé. L'approche multiagent permet de modéliser un réseau de MG comme un système physiquement distribué. Cette thèse étudie principalement le contrôle de coordination dans le réseau MG et sa modélisation à base d'agent.. L' objectif est de promouvoir la performance des contrôles en termes d’efficacité et de fiabilité. Deux méthodes sont envisagées pour permettre l’évolutivité du système, y compris la coordination avec les MG voisins et dans la zone de coordination étendue. Une plateforme de simulation est établie pour valider les approches proposées.Les stratégies de contrôle pour la coordination entre les MG et leurs voisins sont proposées afin de maintenir la charge complète et la sécurité tout en minimisant le coût de production. Le contrôle centralisé dans le groupe de coordination est appliqué à la gestion économique de l’énergie. Il utilise une méthode de Newton-Raphson pour répartir la puissance entre les MG voisins en simplifiant la relation entre le coût de production de MG et sa puissance de sortie. Une approche fondée sur le consensus est adoptée pour calculer le flux de puissance du réseau, et les résultats sont comparés avec la capacité maximale sur la ligne pour assurer un fonctionnement sûr. Pour améliorer encore les avantages économiques, l’approximation de la relation entre la puissance de production de MG et le coût de production est améliorée par une autre stratégie fondée sur la notion de marché. Il construit un marché pour le commerce d’électricité avec les voisins. Cette méthode préserve la vie privée de chaque MG. Le calcul du débit de puissance est simplifié pour être proportionnel à la différence d’angle entre les deux extrémités de la ligne de raccordement. Les deux stratégies sont testées sur plusieurs réseaux MG. Leur performance montre que les deux approches sont évolutives et pourraient économiquement compenser le manque d’approvisionnement en charge dans les MG défectueux.Pour la stratégie de contrôle avec une fiabilité et un profit plus élevés, une stratégie de coordination au sein d’une vaste zone sélectionnée de MG est proposée. L’élargissement de la zone de coordination en fonction des MG voisins fournit plus de sources d’énergie au MG. Il assure suffisamment de puissance pour compenser le déséquilibre et offre plus de choix pour la distribution de puissance. La sélection de la zone de coordination est réalisée par un algorithme évolutionnaire distribué. La programmation quadratique dans Gurobi est utilisée pour résoudre le problème de répartition de puissance. Un autre algorithme génétique est également adopté pour résoudre le problème de la répartition optimale de la puissance avec un coût de production quadratique pour la microturbine. La performance de cette stratégie est testée, et les résultats montrent qu’elle a des avantages en termes de fiabilité, d'évolutivité et de profit par rapport aux méthodes centralisées
As renewable sources penetrate the current electrical system to relief global warming and energy shortage, microgrid (MG) emerges to reduce the impact of intermittent generation on the utility grid. Additionally, it improves the automation and intelligence of the power grid with plug-and-play characteristics. Inserting more MGs into a distribution network promotes the development of the smart grid. Thus MG networks existing in the power system are in prospect. Coordinating them could gain a system with high reliability, low cost, and strong resistance to electrical faults. Achieving these profits relies on developed technologies of communication, control strategy, and corresponding algorithms.Dispatching power in distributed MGs while coordinating elements within the individual MG demands a decentralized control system, in which the multi-agent system possesses advantages. It is applied to the MG network for establishing a physically distributed system. Based on the multi-agent system, this thesis mainly studies the coordination control in the MG network and its modeling. It aims at promoting control performance in terms of efficiency, reliability, economic benefit, and scalability. Two methods are considered to enable the system scalability, including the coordination with neighboring MGs and within the extensive coordinating area. A simulation platform is established to validate the proposed approaches.The control strategies for coordination between MGs and their neighbors are proposed to maintain the complete load supply and global security operation while minimizing the generation cost. Centralized control in the coordination group is applied for economic energy management. It uses a Newton-Raphson method to dispatch power among neighboring MGs by simplifying the relationship between MG generation cost and its output power. An average consensus approach is adopted to calculate the caused network power flow, and the results are compared with the maximal capacity on the line to keep safe operation. To further improve the economic benefits, the approximation of the relationship between MG output power and the caused generation cost is improved by an another strategy based on the market concept. It builds a market for neighboring power trade. This method maintains the operation privacy of individual MG. Power flow calculation is simplified to be proportional to the angle difference between the two terminates of the connecting line. Both strategies are tested on several MG network. Their performance shows that both approaches possess scalability and could economically compensate for the lack of load supply in faulted MG.For the control strategy with higher reliability and profit, a coordination strategy within a selected extensive area of MGs is proposed. Expanding the coordination area based on neighboring MGs provides more energy sources to the demanded MG. It ensures enough power to compensate imbalance and offers more choices for power dispatching. The selection of the coordination area is based on a distributed evolutionary algorithm. Quadratic programming in Gurobi is used to solve the power dispatching problem. Another genetic algorithm is also adopted to solve the problem of optimal power dispatching with a quadratic generation cost for microturbine. The performance of this strategy is tested, and the results show that it has comprehensive advantages on reliability, scalability, and profit compared with centralized methods
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Cutando, Ruiz Laura 1985. "Role of the endocannabinoid system in the control of the cerebellar functions." Doctoral thesis, Universitat Pompeu Fabra, 2015. http://hdl.handle.net/10803/316589.

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The endocannabinoid system is an endogenous neuromodulatory system widely expressed in the central nervous system. It modulates synaptic plasticity and neuronal excitability, and fine-tunes several physiological functions such as, motor coordination, learning and memory, anxiety and nociception, among others. Exogenous or endogenous cannabinoid agonists exert their effects acting on specific cannabinoid receptors heavily expressed in the brain. Cannabinoids agonists are widely used and abused for recreational purposes, but more recently their therapeutic potential in different pathological states has been explored. Important limitations to their use are the possible central adverse effects on cognitive performance or motor coordination. This thesis mainly focuses on the effects of Δ9-tetrahydrocannabinol, the main psychoactive compound of marijuana plant, in the cerebellar functionality, paying special attention to the role of the microglial cells in the regulation of the fine motor coordination functions. The use of biochemical, pharmacological, genetic, and behavioral approaches allowed us to determine the sensitivity of the neuronal/glial circuitry in the regulation of the cerebellar functions and the molecular mechanisms they involved in it.
El sistema endocannabinoid és un sistema endogen neuromodulador àmpliament expressat en el sistema nerviós central. Aquest sistema modula la plasticitat sinàptica i l’excitabilitat neuronal, regulant de manera fina funcions fisiològiques com la coordinació motora, l’aprenentatge, la memòria, l’ansietat i el dolor, entre d’altres. Agonistes cannabinoids exògens o endògens duen a terme els seus efectes actuant específicament sobre els receptors cannabinoids àmpliament expressats en el cervell. Els compostos cannabinoids són extensament utilitzats pel seu ús recreatiu com a drogues d’abús, encara que en els últims anys el seu potencial terapèutic està sent cada cop més estudiat. Una de les principals limitacions del seu ús són els possibles efectes adversos sobre el sistema nerviós central, a nivell cognitiu i sobre la coordinació motora. Aquesta tesis es centra principalment en els efectes del Δ9-tetrahidrocannabinol, el principal component psicoactiu de la planta de la marihuana, sobre la coordinació motora fina. La combinació d’aproximacions bioquímiques, farmacològiques, genètiques i comportamentals ha permès determinar la sensibilitat del circuit glial/neuronal en el control de les funcions cerebelars i els mecanismes i molècules involucrades en aquesta regulació
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Beak, Byungho, and Byungho Beak. "Systematic Analysis and Integrated Optimization of Traffic Signal Control Systems in a Connected Vehicle Environment." Diss., The University of Arizona, 2017. http://hdl.handle.net/10150/626304.

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Traffic signal control systems have been tremendously improved since the first colored traffic signal light was installed in London in December 1868. There are many different types of traffic signal control systems that can be categorized into three major control types: fixed-time, actuated, and adaptive. Choosing a proper traffic signal system is very important since there exists no perfect signal control strategy that fits every traffic network. One example is traffic signal coordination, which is the most widely used traffic signal control system. It is believed that performance measures, such as travel times, vehicle delay, and number of stops, can be enhanced by synchronizing traffic signals over a corridor. However, it is not always true that the coordination will have the same benefits for all the traffic in the network. Most of the research on coordination has focused only on strengthening the major movement along the coordinated routes without considering system-wide impacts on other traffic. Therefore, before implementing a signal control system to a specific traffic network, a thorough investigation should be conducted to see how the control strategy may impact the entire network in terms of the objectives of each type of traffic control system. This dissertation first considers two different kinds of systematic performance analyses for traffic signal control systems. Then, it presents two types of signal control strategies that account for current issues in coordination and priority control systems, respectively. First, quantitative analysis of smooth progression for traffic flow is investigated using connected vehicle technology. Many studies have been conducted to measure the quality of progression, but none has directly considered smooth progression as the significant factor of coordination, despite the fact that the definition of coordination states that the goal is to have smooth traffic flow. None of the existing studies concentrated on measuring a continuous smooth driving pattern for each vehicle in terms of speed. In order to quantify the smoothness, this dissertation conducts an analysis of the speed variation of vehicles traveling along a corridor. A new measure is introduced and evaluated for different kinds of traffic control systems. The measure can be used to evaluate how smoothly vehicles flow along a corridor based on the frequency content of vehicle speed. To better understand the impact of vehicle mode, a multi-modal analysis is conducted using the new measure. Second, a multi-modal system-wide evaluation of traffic signal systems is conducted. This analysis is performed for traffic signal coordination, which is compared with fully actuated control in terms of a systematic assessment. Many optimization models for coordination focus mainly on the objective of the coordinated route and do not account for the impacts on side street movements or other system-wide impacts. In addition, multi-modality is not considered in most optimized coordination plans. Thus, a systematic investigation of traffic signal coordination is conducted to analyze the benefits and impacts on the entire system. The vehicle time spent in the system is measured as the basis of the analysis. The first analysis evaluates the effect of coordination on each route based on a single vehicle mode (regular passenger vehicles). The second analysis reveals that how multi-modality affects the performance of the entire system. Third, in order to address traffic demand fluctuation and traffic pattern changes during coordination periods, this dissertation presents an adaptive optimization algorithm that integrates coordination with adaptive signal control using data from connected vehicles. Through the algorithm, the coordination plan can be updated to accommodate the traffic demand variation and remain optimal over the coordination period. The optimization framework consists of two levels: intersection and corridor. The intersection level handles phase allocation in real time based on connected vehicle trajectory data, while the corridor level deals with the offsets optimization. The corridor level optimization focuses on the performance of the vehicle movement along the coordinated phase, while at the intersection level, all movements are considered to create the optimal signal plan. The two levels of optimizations apply different objective functions and modeling methodologies. The objective function at the intersection level is to minimize individual vehicle delay for both coordinated and non-coordinated phases using dynamic programming (DP). At the corridor level, a mixed integer linear programming (MILP) is formulated to minimize platoon delay for the coordinated phase. Lastly, a peer priority control strategy, which is a methodology that enhances the multi modal intelligent traffic signal system (MMITSS) priority control model, is presented based on peer-to-peer (P2P) and dedicated short range communication (DSRC) in a connected vehicle environment. The peer priority control strategy makes it possible for a signal controller to have a flexible long-term plan for prioritized vehicles. They can benefit from the long-term plan within a secured flexible region and it can prevent the near-term priority actions from having a negative impact on other traffic by providing more flexibility for phase actuation. The strategy can be applied to all different modes of vehicles such as transit, freight, and emergency vehicles. Consideration for far side bus stops is included for transit vehicles. The research that is presented in this dissertation is constructed based on Standard DSRC messages from connected vehicles such as Basic Safety Messages (BSMs), Signal Phasing and Timing Messages (SPaTs), Signal Request Messages (SRMs), and MAP Messages, defined by Society of Automotive Engineers (SAE) (SAE International 2016).
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GIMENEZ, JOSE-LUIS. "Contribution a la decomposition de systemes interconnectes par programmation dynamique non serielle : application a des systemes de puissance." Toulouse 3, 1989. http://www.theses.fr/1989TOU30049.

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Bouteraa, Yassine. "Commande distribuée et synchronisation de robots industriels coopératifs." Thesis, Orléans, 2012. http://www.theses.fr/2012ORLE2082/document.

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Cette thèse développe les lois de coordination de systèmes de Lagrange. Elle propose en premier lieu une stratégie complètement décentralisée qui se base sur la technique de cross-coupling pour la commande d'un groupe de robots, appelé réseau, qui synchronisent leurs mouvements en suivant une trajectoire désirée. Cette stratégie est étendue pour faire face à l'incertitude paramétrique des robots ainsi qu’aux retards fréquemment rencontrés dans les applications pratiques de réseaux de communication. Une deuxième architecture basée sur la théorie des graphes est proposée pour les réseaux à leader. L'approche développée est considérée hybride. Une extension adaptative à base de réseaux de neurones est développée pour traiter les cas d'incertitude paramétrique. La stratégie conçue prend en considération les délais dans la réception des données. En se basant sur la notion de système en chaîne, la théorie des graphes, le concept de la passivité et la technique du backstepping, une nouvelle méthodologie de la conception de contrôleur de synchronisation pour une classe de systèmes sous-actionnés est développée. Afin d’avoir la possibilité d’implémenter ces stratégies de contrôle, on a développé une plate-forme d'expérimentation pour la robotique industrielle coopérative
This thesis investigates the issue of designing decentralized control laws to cooperatively control a team of robot manipulators. The purpose is to synchronize their movements while tracking common desired trajectory. Based on a combination of Lyapunov direct method and cross-coupling technique, To account for unmatched uncertainties, the proposed decentralized control laws are extended to an adaptive synchronization tracking controllers. Moreover, due to communication imperfection, time delay communication problems are considered in the performance analysis of the controllers. Another relevant problem for distributed synchronized systems is the leader-follower control problem. In this strategy, a decentralized control laws based on the backstepping scheme is proposed to deal with a leader-follower multiple robots structure. Based on graph theory, the coordination strategy combines the leader follower control with the decentralized control. The thesis, also considers the cooperative movement of under- actuated manipulators tracking reference trajectories defined by the user. The control problem for a network of class of under-actuated systems is considered. The approach we adopted in this thesis consists in decomposing the under-actuated manipulators into a cascade of passive subsystems that synchronize with he other neighbors subsystems. The resulting synchronized control law is basically a combination of non-regular backstepping procedure aided with some concepts from graph theory. The proposed controllers are validated numerically, assuming that the underlying communication graph is strongly connected. To implement these control strategies, we developed an experimental platform made of three robot manipulators
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Tanguy, Roger. "Un reseau mobiles autonomes pour l'apprentissage de la communication." Paris 6, 1987. http://www.theses.fr/1987PA066640.

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Presentation de la realisation materielle et logicielle d'un reseau de mobiles autonomes et programmables destine a l'apprentissage d'actions elementaires et de concepts tels que la communication et la coordination
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Kazzaz, Mohammed Yasser al. "Sur l'ordonnancement d'atelier de fabrication : approche hiérarchisée et fonctionnement en boucles de pilotage." Grenoble INPG, 1989. http://www.theses.fr/1989INPG0050.

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On etudie le probleme de l'ordonnancement des travaux dans les ateliers de fabrication. Les differentes caracteristiques et aspects du probleme sont traites sous une vue globale relevant d'une analyse systematique d'automaticien
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25

Kissai, Moad. "Optimal Coordination of Chassis Systems for Vehicle Motion Control." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLY004/document.

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Le contrôle global du châssis a fait récemment l'objet d'une attention particulière. Cela serait motivé surtout par l’approche des véhicules entièrement autonomes. Ces véhicules, en particulier le niveau 5 d’automatisation SAE (J3016), devraient remplacer le conducteur humain dans presque toutes les situations. Le véhicule automatisé devrait être capable de gérer en harmonie des situations couplées où sont intégrés le contrôle longitudinal, latéral et éventuellement vertical. Pour ce faire, le véhicule dispose de plusieurs systèmes intégrés par axe de contrôle. En effet, les équipementiers automobiles et les nouveaux acteurs de l'industrie automobile proposent continuellement de nouvelles solutions pour satisfaire des performances bien spécifiques. Le constructeur automobile doit quant à lui coordonner différents sous-systèmes provenant de différentes parties prenantes afin de garantir une expérience de conduite fiable et confortable. Jusqu'à présent, les constructeurs automobiles privilégiaient des solutions simples consistant à ajouter une couche de coordination en aval des sous-systèmes concurrents afin de limiter les potentiels conflits. La plupart des stratégies adoptées consistent à prioriser un système par rapport à un autre en fonction de certains scénarios conflictuels prévisibles. Les véhicules autonomes ont besoin de sous-systèmes supplémentaires pour fonctionner en toute sécurité. Ainsi, les interactions entre les sous-systèmes s'amplifieront au point de devenir imprévisibles. Cette thèse met l'accent sur l'approche de coordination qui devrait être adoptée par les véhicules du futur. En particulier, la couche de coordination est déplacée en amont des sous-systèmes autonomes pour assurer une distribution de commande optimale. Cette couche agit comme un superviseur basé sur des algorithmes d'allocation optimale du contrôle. La synthèse des correcteurs repose sur les théories du contrôle robuste permettant de faire face aux changements environnementaux et aux incertitudes paramétriques et dynamiques du véhicule. Les résultats ont d’abord montré que même en ce qui concerne les véhicules actuels, l’approche en amont peut offrir des avantages supplémentaires pour ce qui est de la résolution de problèmes à objectifs multiples. En outre, l’approche en amont permet de coordonner les sous-systèmes des véhicules présentant une sur-actionnement plus élevé. La tolérance aux pannes peut être assurée entre des systèmes de châssis complètement différents, et des objectifs qualitatifs, s'ils sont rigoureusement formalisés, peuvent être satisfaits. Plus les sous-systèmes seront nombreux à l'avenir, plus l'approche en amont deviendrait pertinente pour le contrôle du mouvement des véhicules. Nous espérons que les avantages conséquents présentés dans cette thèse grâce à une approche de coordination en amont optimale encourageraient les constructeurs automobiles et leurs équipementiers à opter pour des solutions plus ouvertes, à proposer ensemble les normalisations nécessaires et accélérer ainsi le développement des véhicules autonomes
A large interest has been given recently to global chassis control. One of the main reasons for this would be the approach of fully autonomous vehicles. These vehicles, especially the SAE (J3016) level 5 of automation, are expected to replace the human driver in all situations. The automated vehicle should be able to manage coupled situations in harmony where longitudinal control, lateral control, and eventually vertical control are involved. To do so, the vehicle has more than one embedded system per control axis. Equipment suppliers and new entering automotive actors are continually proposing new solutions to satisfy a specific performance required from future passenger cars. Consequently, the car manufacturer has to coordinate different subsystems coming from different stakeholders to ensure a safe and comfortable driving experience. Until these days, car manufactures favoured simple solutions consisting on adding a coordination layer downstream the competing subsystems in order to mitigate eventual conflicts. Most of strategies adopted consist on prioritizing one system over another depending on predictable conflicting scenarios. Autonomous vehicles need additional subsystems to operate safely. Interactions between these subsystems will increase to the point of becoming unpredictable. This thesis focus on the coordination approach that should be adopted by future vehicles. Particularly, the coordination layer is moved upstream the standalone subsystems to ensure an optimal control distribution. This layer acts as a supervisor depending on optimization-based control allocation algorithms. The control synthesis is based on robust control theories to face environmental changes and the vehicle’s parameters and dynamics uncertainties. Results showed first that even regarding today’s vehicles, the upstream approach can offer additional advantages when it comes to multiple objectives problems solving. In addition, the upstream approach is able to coordinate subsystems of vehicles with a higher over-actuation. Fault-tolerance can be ensured between completely different chassis systems, and qualitative objectives, if rigorously formalized, can be satisfied. The more numerous subsystems will get in the future, the more relevant the upstream approach would become to vehicle motion control. We expect that the important benefits shown in this thesis thanks to an optimal upstream coordination approach would encourage car manufacturers and equipment to switch towards more open solutions, propose together the necessary standardizations, and accelerate the autonomous vehicles development
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Schneider, Antoine. "Contribution à l'identification et la commande de systèmes stochastiques discrets par des méthodes hiérarchisées : Application au modèle d'un convertisseur d'acier." Nancy 1, 1987. http://www.theses.fr/1987NAN10248.

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Al, Turki Sulaiman A. "Coordination and concurrency in workflow management systems." Thesis, University of East Anglia, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.251712.

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28

Speranzon, Alberto. "Coordination, Consensus and Communication in Multi-robot Control Systems." Doctoral thesis, Stockholm : Automatic control, School of Electrical Engineering, Royal Institute of Technology, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3955.

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29

Wang, Yuquan. "Reactive control and coordination of redundant robotic systems." Doctoral thesis, KTH, Datorseende och robotik, CVAP, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-182680.

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Redundant robotic systems, in terms of manipulators with one or twoarms, mobile manipulators, and multi-agent systems, have received an in-creasing amount of attention in recent years. In this thesis we describe severalways to improve robotic system performance by exploiting the redundancy. As the robot workspace becomes increasingly dynamic, it is common towork with imperfect geometric models of the robots or its workspace. Inorder to control the robot in a robust way in the presence of geometric uncer-tainties, we propose to assess the stability of our controller with respect to acertain task by deriving bounds on the geometric uncertainties. Preliminaryexperimental results support the fact that stability is ensured if the proposedbounds on the geometric uncertainties are fulfilled. As a non-contact measurement, computer vision could provide rich infor-mation for robot control. We introduce a two step method that transformsthe position-based visual servoing problem into a quadratic optimization prob-lem with linear constraints. This method is optimal in terms of minimizinggeodesic distance and allows us to integrate constraints, e.g. visibility con-straints, in a natural way. In the case of a single robot with redundant degrees of freedom, we canspecify a family of complex robotic tasks using constraint based programming(CBP). CBP allows us to represent robotic tasks with a set of equality andinequality constraints. Using these constraints we can formulate quadraticprogramming problems that exploit the redundancy of the robot and itera-tively resolve the trade-off between the different constraints. For example, wecould improve the velocity or force transmission ratios along a task-dependent direction using the priorities between different constraints in real time. Using the reactiveness of CBP, we formulated and implemented a dual-armpan cleaning task. If we mount a dual-arm robot on a mobile base, we proposeto use a virtual kinematic chain to specify the coordination between the mobilebase and two arms. Using the modularity of the CBP, we can integrate themobility and dual-arm manipulation by adding coordination constraints intoan optimization problem where dual-arm manipulation constraints are alreadyspecified. We also found that the reactiveness and modularity of the CBPapproach is important in the context of teleoperation. Inspired by the 3Ddesign community, we proposed a teleoperation interface control mode thatis identical to the ones being used to locally navigate the virtual viewpoint ofmost Computer Aided Design (CAD) softwares. In the case of multiple robots, we combine ideas from multi-agent coopera-tive coverage control, with problem formulations from the resource allocationfield, to create a distributed convergent approach to the resource positioningproblem.

QC 20160224

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Gustavi, Tove. "Control and coordination of mobile multi-agent systems." Doctoral thesis, Stockholm : Optimization and Systems Theory, Royal Institute of Technology, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-10910.

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Santos, Luiz Cezar dos. "A coordenação entre os segmentos perna e coxa no andar : uma análise a partir da teoria dos sistemas dinâmicos." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 1995. http://hdl.handle.net/10183/1486.

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Utilizando-se entre a perna e a coxa os princípios da Teoria dos Sistemas Dinâmicos, foi estudada a coordenação intra-membros durante o andar em 16 sujeitos do sexo feminino. Os movimentos da perna e da coxa e suas relações foram analisados dinamicamente como sistemas acoplados de ciclo limite. Os sujeitos foram filmados lateralmente executando o andar em duas situações experimentais: normal e com uma sandália na perna direita na proporção de 5% do comprimento do segmento inferior. Os dados transformados em variáveis cinemáticas possibilitaram a análise da coordenação em termos de ângulos de fase, ponto de coordenação e fase relativa. Através dos dados angulares, foram testadas as propriedades dos osciladores não-lineares de ciclo limite. Os resultados indicaram que os segmentos apresentam uma órbita atrativa específica para cada um deles, que se mantém invariante ao longo das idades. Esta órbita atrativa representa a organização espaço-temporal do segmento durante o andar, servindo também para a visualização da quantidade de energia dissipada por parte de cada segmento. A análise dos ângulos de fase no momento da reversão, do ponto de coordenação e da fase relativa possibilitaram a identificação do treinamento mútuo e da estabilidade estrutural.
Based on the principles of the Theory of Dynamic Systems, 16 female subjects were studied as to their intra-limb coordination during walk. The movements of lower leg and thigh have been dynamically analised, - as well as their relation, - as limit-cycle coupled systems. Subjects were video-taped laterally, as they performed natural walking movements under two experimental situations: barefoot and with a sandal on the right foot with a thickness of 5% the length of the lower segment. Converted into kinematic variables, the data allowed the analysis of the coordination in terms of phase angle, point of coordination and relative coordination. The angular data made it possible to test the properties of the non-linear limit-cycle oscilator. Results pointed out that each segment involved in walking draws a specific attractive orbit, which is kept invariable throughout the ages. This attractive orbit represents the limb’s spacetemporal organization during walk, being, furthermore, an indication as to how much energy is being dissipated by each segment. The analysis of phase angles at the moment of limb reversion, the point of coordination and the relative phase made it possible to identify mutual training and structural stability.
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Smith, Brian Stephen. "Automatic coordination and deployment of multi-robot systems." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/28248.

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Thesis (M. S.)--Electrical and Computer Engineering, Georgia Institute of Technology, 2009.
Committee Chair: Dr. Magnus Egerstedt; Committee Co-Chair: Dr. Ayanna Howard; Committee Member: Dr. David Taylor; Committee Member: Dr. Frank Dellaert; Committee Member: Dr. Ian Akyildiz; Committee Member: Dr. Jeff Shamma.
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Kohagura, Monique Sachie. "Local coordination medium access control for wireless sensor networks." Online access for everyone, 2008. http://www.dissertations.wsu.edu/Thesis/Summer2008/m_kohagura_050808.pdf.

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Johansson, Alexander. "Strategic Decision-Making in Platoon Coordination." Licentiate thesis, KTH, Reglerteknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-275670.

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The need for sustainable transportation solutions is urgent as the demand for mobility of goods and people is expected to multiply in the upcoming decades. One promising solution is truck platooning, which shows great potential in reducing the fuel consumption and operational costs of trucks.  In order to utilize the benefits of truck platooning to the fullest, trucks with different routes in a transportation network need coordination to efficiently meet and form platoons. This thesis addresses platoon coordination when trucks form  platoons at hubs, where some trucks need to wait for others in order to meet, and there is a reward for platooning and a cost for waiting. Three contributions on the topic platoon coordination are presented in this thesis. In the first contribution, we consider platoon coordination among trucks that have pre-defined routes in a network of hubs, and the travel times are either deterministic or stochastic. The trucks are owned by competing transportation companies, and each truck decides on its waiting times at hubs in order to optimize its own operational cost. We consider a group of trucks to form a platoon if it departs from a hub and enters the road at the same time. The strategic interaction among trucks when they coordinate for platooning is modeled by non-cooperative game theory, and the Nash equilibrium is considered as the solution concept when the trucks make their decisions at the beginning of their journeys. In case of stochastic travel times, we also develop feedback-based solutions wherein trucks repeatedly update their decisions. We show in a simulation study of the Swedish transportation network that the feedback-based solutions achieve platooning rates up to 60 %. In the second contribution, we propose models for sharing the platooning profit among platoon members. The platooning benefit is not equal for all trucks in a platoon; typically, the lead truck benefits less than its followers. The incentive for transportation companies to cooperate in platooning may be low unless the profit is shared. We formulate platoon coordination games based on profit-sharing models, and in a simulation of a single hub, the outcomes of the platoon coordination games are evaluated. The evaluation shows that the total profit achieved when the trucks aim to maximize their own profits, but the platooning benefit is evened out among platoon members, is nearly as high as when each truck aims to maximize the total profit in the platooning system.  In the last contribution, we study a problem where trucks arrive to a hub according to a stochastic arrival process. The trucks do not share a priori information about their arrivals; this may be sensitive information to share with others. A coordinator decides, based on the statistical distribution of arrivals, when to release the trucks at the hub in the form of a platoon. Under the assumption that the arrivals are independent and identically distributed, we show that it is optimal to release the trucks at the hub when the number of trucks exceeds a certain threshold. This contribution shows that simple and dynamic coordination approaches can obtain a high profit from platooning, even under high uncertainty and limited a priori information.
Under de kommande decennierna förväntas efterfrågan på transport av varor och passagerare mångfaldigas, vilket innebär att behovet av hållbara transportlösningar är brådskande. En lovande lösning är konvojkörning, som visar stor potential att minska bränsleförbrukningen och driftskostnaderna för lastbilar. För att utnyttja fördelarna med konvojkörning till fullo behöver lastbilar koordineras för att effektivt mötas och bilda konvojer. Den här avhandlingen behandlar koordinering av lastbilar som kan bilda konvojer på transporthubbar, där vissa lastbilar måste vänta på andra lastbilar för att bilda konvojer, och det finns en belöning för konvojkörning och en kostnad för att vänta. Tre bidrag som behandlar konvojkoordinering presenteras i den här avhandlingen. Det första bidraget behandlar koordinering av lastbilar med förutbestämda rutter i ett transportnätverk med deterministiska eller stokastiska restider. Lastbilarna ägs av konkurrerande transportföretag, och varje lastbil beslutar om sina väntetider på hubbarna längs med sin rutt för att optimera sin driftskostnad. Vi antar att lastbilar bildar en konvoj om de avgår från en hubb och kör in på vägen samtidigt. Den strategiska interaktionen mellan lastbilar när de koordinerar för konvojbildning modelleras med icke-kooperativ spelteori, och vi betraktar Nashjämvikt som lösningskoncept när lastbilarna beslutar om sina väntetider i början av sina resor. I fallet med stokastiska restider utvecklar vi även lösningar där lastbilarna tillåts uppdatera sina väntetider längs med sina resor. I en simuleringsstudie över det svenska transportnätverket visas att när lastbilarna tillåts uppdatera sina väntetider uppnås en konjovkörningsgrad på 60%. I det andra bidraget utreds modeller för att dela på vinsten från konvojkörning. Fördelarna med konvojkörning är inte lika för alla lastbilar i en konvoj; vanligtvis är fördelen större för följarlastbilarna än för ledarlastbilen. Således kan incitamenten för transportföretag att samarbeta i form av konvojkörning vara låga om inte vinsterna från konvojkörning delas. Baserat på vinstdelningsmodeller formulerar vi konvojkoordineringsspel. I en simulering av en transporthubb utvärderar vi utfallet från konvojkoordinationsspelen. Det visar sig att den totala vinsten som uppnås när lastbilarna försöker maximera sina egna vinster, men vinsten från konvojkörning jämnas ut helt bland konvojmedlemmar, är nästan lika hög som när varje lastbil försöker att maximera den totala vinsten i systemet. I det sista bidraget studeras ett koordineringsproblem där lastbilar anländer till en transporthubb enligt en stokastisk ankomstprocess. Lastbilarna delar inte förhandsinformation om sina ankomster; detta kan vara känslig information att dela. En koordinator bestämmer, baserat på den statistiska sannolikhetsfördelningen av ankomster, när lastbilarna på transporthubben ska släppas iväg i form av en konvoj. Under antagandet att ankomsterna är statistiskt oberoende och likafördelade, visar vi att det är optimalt att släppa iväg lastbilarna från transporthubben i form av en konvoj när antalet lastbilar överskrider en viss tröskel. Detta bidrag visar att enkla och dynamiska koordineringsmetoder kan erhålla en hög vinst från konvojkörning, även under hög osäkerhet och begränsad förhandsinformation.

Länk till den offentliga granskningen tillkännages via: https://www.kth.se/profile/alexjoha

QC 20200609

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35

Hess, Martin. "Motion coordination and control in systems of nonholonomic autonomous vehicles." Würzburg Univ.-Bibliothek, 2010. http://d-nb.info/1001075382/34.

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36

Hellal, Abdelhafid. "Control coordination of SVCs for voltage regulation in power systems." Thesis, McGill University, 1991. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=70286.

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One of the principal functions of static var compensators (SVCs) in a transmission system is the voltage control at the point of connection. As power and transmission systems have grown considerably in the last decades, many systems have been interconnected for economic reasons. The use of SVCs became more important as the systems were required to operate at higher power levels, which led to a reduction in the stability margin. Increasing the number of SVCs in a network is one of the solutions, but it leads to undesirable interactions among them, which affect the stability limits. Control coordination of these SVCs is considered a good alternative to allow power systems to operate at higher power levels with the required stability margin, as well as to increase the damping of critical modes of oscillation.
This study presents the possibility of improving the effectiveness of SVCs in a system through the concept of SVC control coordination for voltage regulation, in linearized power systems. A concept of coordination of several SVC units, operating on the same system bus of a network, based on averaging the SVC current outputs according to their dynamic reactive capabilities as defined by their slope reactances, has been elaborated. Then, a control coordination concept relevant to many SVC units connected to different buses of the system has been presented and described.
The methodologies used to describe these concepts have been explained, and simulation results were presented.
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37

Abou-Kandil, Hisham. "Elaboration de structures de commande hiérarchisées : approches monocritère et multicritères." Paris 6, 1986. http://www.theses.fr/1986PA066074.

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Pour un problème de commande optimale linéaire-quadratique monocritère les lois de commande partiellement en boucle fermée à deux niveaux sont étudiées. Une généralisation des moyens de synthèse de ces lois est proposée. Pour les problèmes multicritères linéaires-quadratiques, l'utilisation des stratégies de Nash et de Stackelberg nécessite la résolution d'un ensemble d'équations matricielles couplées. La solution analytique exacte de tous les jeux de Stackelberg en boucle ouverte et d'une large classe des jeux de Nash est obtenue. Ces résultats s'appuient sur les propriétés des spectres des matrices caractérisant les conditions nécessaires à satisfaire par les différentes stratégies.
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38

Twu, Philip Y. "Control of multi-agent networks: from network design to decentralized coordination." Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/43713.

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This dissertation presents a suite of design tools for multi-agent systems that address three main areas: network design, decentralized controller generation, and the synthesis of decentralized control strategies by combining individual decentralized controllers. First, a new metric for quantifying heterogeneity in multi-agent systems is presented based on combining different notions of entropy, and is shown to overcome the drawbacks associated with existing diversity metrics in various scientific fields. Moreover, a new method of controlling multi-agent networks through the single-leader network paradigm is presented where by directly exploiting the homogeneity of agent capabilities, a network which is not completely controllable can be driven closer to a desired target configuration than by using traditional control techniques. An algorithm is presented for generating decentralized control laws that allow for agents to best satisfy a desired global objective, while taking into account network topological constraints and limitations on how agents can compute their control signals. Then, a scripting tool is developed to aid in specifying sequences of decentralized controllers to be executed consecutively, while helping ensure that the required network topological requirements needed for each controller to execute properly are maintained throughout mode switches. Finally, the underlying concepts behind the developed tools are showcased in three example applications: distributed merging and spacing for heterogeneous aircraft during terminal approaches, collaborative multi-UAV convoy protection in dynamic environments, and an educational tool used to teach a graduate-level networked controls course at the Georgia Institute of Technology.
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39

Adaldo, Antonio. "Event-triggered control of multi-agent systems: pinning control, cloud coordination, and sensor coverage." Licentiate thesis, KTH, Reglerteknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-192342.

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A multi-agent system is composed of interconnected subsystems, or agents. In control of multi-agent systems, the aim is to obtain a coordinated behavior of the overall system through local interactions among the agents. Communication among the agents often occurs over a wireless medium with finite capacity. In this thesis, we investigate multiagent control systems where inter-agent communication is modelled by discrete events triggered by state conditions. In the first part, we consider event-triggered pinning control for a network of agents with nonlinear dynamics and time-varying topologies. Pinning control is a strategy to steer the behavior of a multi-agent system in a desired manner by controlling only a small fraction of the agents. We express the controllability of the network in terms of an average value of the network connectivity over time, and we show that all the agents can be driven to a desired reference trajectory. In the second part, we propose a control algorithm for multi-agent systems where inter-agent communication is substituted with a shared remote repository hosted on a cloud. Communication between each agent and the cloud is modelled as a sequence of events scheduled recursively by the agent. We quantify the connectivity of the network and we show that it is possible to synchronize the multi-agent system to the same state trajectory, while guaranteeing that two consecutive cloud accesses by the same agent are separated by a finite time interval. In the third part, we propose a family of distributed algorithms for coverage and inspection tasks for a network of mobile sensors with asymmetric footprints. We develop an abstract model of the environment under inspection and define a measure of the coverage attained by the sensor network. We show that the sensor network attains nondecreasing coverage, and we characterize the equilibrium configurations. The results presented in the thesis are corroborated by simulations or experiments.

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40

Kingston, Peter. "Multi-agent coordination: fluid-inspired and optimal control approaches." Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/43714.

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Multiagent coordination problems arise in a variety of applications, from satellite constellations and formation flight, to air traffic control and unmanned vehicle teams. We investigate the coordination of mobile agents using two kinds of approaches. In the first, which takes its inspiration from fluid dynamics and algebraic topology, control authority is split between mobile agents and a network of static infrastructure nodes - like wireless base stations or air traffic control towers - and controllers are developed that distribute their computation throughout this network. In the second, we look at networks of interconnected mechanical systems, and develop novel optimal control algorithms, which involve the computation of optimal deformations of time- and output- spaces, to achieve approximate formation tracking. Finally, we investigate algorithms that optimize these controllers to meet subjective criteria of humans.
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41

Yackoski, Justin. "High performance medium access control protocols for decentralized wireless networks using local coordination." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 156 p, 2009. http://proquest.umi.com/pqdweb?did=1833647411&sid=1&Fmt=2&clientId=8331&RQT=309&VName=PQD.

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42

Hagio, Shota. "Muscle synergy for coordinating redundant motor system." Kyoto University, 2016. http://hdl.handle.net/2433/215620.

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Kyoto University (京都大学)
0048
新制・課程博士
博士(人間・環境学)
甲第19794号
人博第765号
新制||人||184(附属図書館)
27||人博||765(吉田南総合図書館)
32830
京都大学大学院人間・環境学研究科共生人間学専攻
(主査)教授 神﨑 素樹, 教授 森谷 敏夫, 教授 石原 昭彦
学位規則第4条第1項該当
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43

Deshpande, Paresh Ravindra. "Performance based coordination control of multi-agent systems subject to time delays." Thesis, University of Leicester, 2013. http://hdl.handle.net/2381/27802.

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This thesis considers the design of distributed state and output feedback control algorithms for linear multi-agent systems with performance guarantees in the presence of delays. The multi-agent systems considered are assumed to exchange relative information over an information network. As a first contribution, a novel distributed state feedback control design method with a sub-optimal LQR performance is developed for a network of multiple agents. For the control design process, it is assumed that the exchange of relative information is instantaneous. A stability analysis of the proposed control law is performed by incorporating delays in relative information to ascertain the maximum possible delay that can be accommodated by the communication network. Subsequently, the assumption of the exchange of instantaneous relative information in the control design process is relaxed and the relative information is assumed to be delayed. The system is then represented as a time-delay system. Distributed state feedback control synthesis methods are then developed for the system with a certain level of LQR performance. In the above contributions, the time delay analysis and the development of delay based control methods, it is implicitly assumed that delays are detrimental to achieving cooperative tasks for a multi-agent system. Subsequently, positive effects of delays in communication of relative information are explored. For this a network of vehicles described by double integrator dynamics, which cannot be stabilized by static output feedback without delays, is considered. A novel control design method to achieve exponential stabilization of such a multi-agent system by static output feedback using delayed relative information is developed. Conclusions are drawn from the results of the research presented in this thesis and a few directions for future work are identified.
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Chen, Wei. "Designing an extended set of coordination mechanisms for multi-agent systems." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file 1.46 Mb., 240 p, 2006. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:3200551.

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45

Li, Sen. "Transactive Control for Large-Scale Cyber-Physical Systems." The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1511397616555155.

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46

Buck, Sebastian. "Experience-based control and coordination of autonomous mobile systems in dynamic environments." [S.l. : s.n.], 2003. http://deposit.ddb.de/cgi-bin/dokserv?idn=970263929.

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47

Hess, Martin [Verfasser]. "Motion coordination and control in systems of nonholonomic autonomous vehicles / Martin Hess." Würzburg : Univ.-Bibliothek, 2010. http://d-nb.info/1001075382/34.

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48

Mallem, Badis. "Modélisation, analyse et commande des grands systèmes électriques interconnectés." Phd thesis, École normale supérieure de Cachan - ENS Cachan, 2010. http://tel.archives-ouvertes.fr/tel-00557829.

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Cette thèse porte sur la modélisation, la réduction et la commande des grands systèmes électriques.En terme de modélisation et de réduction, l'objectif principal est de développer une méthode de réduction des modèles dynamiques des systèmes électriques. Cette réduction a pour objet de répondre à une situation particulière dans laquelle toutes les données du système à réduire ne sont pas connues.En terme de commande, l'objectif est la conception de commandes robustes coordonnées pour répondre aux nouvelles contraintes des grands systèmes électriques. Ces approches doivent respecter trois niveaux de coordination et deux nouvelles contraintes. Les trois niveaux de coordination concernent la prise en compte simultanée des oscillations électromécaniques interzones et locaux, la coordination de la synthèse de régulateurs pour plusieurs alternateurs, et la coordination du réglage des paramètres (gains et constantes de temps) des régulateurs de tension (les boucles stabilisatrices PSS) avec le réglage des paramètres des régulateurs de turbine des alternateurs. Les contraintes sont liées à la stabilité et la robustesse des régulateurs proposés.
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49

Smith, Dean L. "Postural Coordination During Quiet Stance and Suprapostural Activity." Miami University / OhioLINK, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=miami1091063392.

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50

Kyrkjebø, Erik. "Motion Coordination of Mechanical Systems : Leader-Follower Synchronization of Euler-Lagrange Systems using Output Feedback Control." Doctoral thesis, Norwegian University of Science and Technology, Faculty of Information Technology, Mathematics and Electrical Engineering, 2007. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-2224.

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his thesis proposes two motion synchronization approaches to coordinate the motion of a follower to a leader within the Euler-Lagrange system framework. The information requirements from the leader are that of position and orientation only, i.e. the mathematical model with its parameters and the velocity and acceleration of the leader are considered unknown and unmeasured.

The follower is responsible for the control action necessary to coordinate the systems, and the leader system is free to manoeuvre independently of the follower. There is no off-line synchronization of the systems through predefined paths or trajectories. %The parameters of the dynamic model of the leader are unknown, and its unmeasured system states (velocity and acceleration) must be estimated in order to be utilized in the coordination controller of the follower.

The concept of motion control of multiple objects is discussed in terms of the different forms of synchronization; cooperation (where all objects contribute equally) and coordination (where one object governs the motion of the others). Motivating examples and literature provide the motivation for the definition of two motion coordination problems. The output reference state feedback synchronization problem is defined by utilizing only output feedback from the desired motion reference, while assuming state feedback for the follower in the coordination control law. Furthermore, to increase the usefulness of the proposed control schemes and to provide robustness towards loss or poor quality of velocity measurements, the requirements of state information for the follower are alleviated in the definition of the output reference output feedback synchronization problem utilizing only output information of both the leader and the follower in the synchronization design. Furthermore, the necessary tools of stability are presented to prove that the proposed coordination schemes are uniformly ultimately bounded or practically asymptotically stable closed-loop systems.

In order to solve the output reference state feedback and the output reference output feedback synchronization problems, an observer-controller scheme is proposed that estimates the unknown states of the leader indirectly through a nonlinear model-based error observer. The observer-controller approach makes the follower system a physical observer of the leader system through the coupled observer and controller error-dynamics. A second nonlinear model-based observer is introduced for the follower to remove the state feedback assumption. The observer-controller scheme is proven to be uniformly globally ultimately bounded when utilizing state feedback of the follower in the coordination control law, and to be uniformly semiglobally ultimately bounded when utilizing only output feedback of the follower in the coordination control law. The observer-controller approach to motion coordination is studied through simulations and experiments, and a back-to-back comparison between ideal simulations and practical experiments is presented to allow for a discussion on the performance of the scheme under modelling errors, measurement noise and external disturbances. The observer-controller scheme is demonstrated to be suitable for practical applications.

Furthermore, a virtual vehicle scheme is proposed to solve the output reference state/ output feedback synchronization problems through a cascaded approach. The virtual vehicle approach is based on a two-level control structure to decouple the estimation and coordination error dynamics in the stability analysis and the tuning process. The virtual vehicle scheme estimates the unknown states of the leader through a virtual kinematic vehicle stabilized to the output of the leader system. A stable first-order velocity filter is introduced for the follower to remove the state feedback assumption. The virtual vehicle scheme is proven to be uniformly globally practically asymptotically stable when utilizing state feedback of the follower in the coordination control law, and to be uniformly semiglobally practically asymptotically stable when utilizing only output feedback of the follower in the coordination control law. Application of the virtual vehicle scheme to both vehicle coordination and robot manipulator coordination is presented, and the virtual vehicle approach to motion coordination is studied through simulations and experiments. The virtual vehicle scheme is demonstrated to be suitable for practical applications. In addition, an extension to a dynamic synchronization scheme is proposed to impose a smooth behaviour on the follower during a change of relative position.

The proposed coordination schemes are compared in terms of estimation principle, performance and robustness. Simulation studies compare the performance of the proposed schemes in terms of gain tuning and bounds on the closed-loop errors, and in terms of impact from external disturbances, modelling errors and measurement noise. The two coordination schemes are distinguished by concept rather than by performance, and both of the proposed schemes are believed to be suitable for practical implementation in coordination applications.

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