To see the other types of publications on this topic, follow the link: Agents and autonomous systems.
Dissertations / Theses on the topic 'Agents and autonomous systems'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 dissertations / theses for your research on the topic 'Agents and autonomous systems.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
1
Meshref, Hossam. "Modeling Autonomous Agents' Behavior Using Neuro-Immune Networks." Diss., Virginia Tech, 2002. http://hdl.handle.net/10919/28473.
Full textAbstract:
Autonomous robots are expected to interact with their dynamic changing environment. This interactions requires certain level of behavior based Intelligence, which facilitates the dynamic adaptation of the robot behavior accordingly with his surrounding environment. Many researches have been done in biological information processing systems to model the behavior of an autonomous robot. The Artificial Immune System (AIS) provides new paradigm suitable for dynamic problem dealing with unknown environment rather than a static problem. The immune system has some features such as memory, tolerance, diversity and more features that can be used in engineering applications.
The immune system has an important feature called meta-dynamics in which new species of antibodies are produced continuously from the bone marrow. If the B-Cell (robot) cannot deal with the current situation, new behaviors (antibodies) should be generated by the meta dynamics function. This behavior should be incorporated into the existing immune system to gain immunity against new environmental changes. We decided to use a feed forward Artificial Neural Network (ANN) to simulate this problem, and to build the AIS memory.
Many researchers have tried to tackle different points in mimicking the biological immune system, but no one previously has proposed such an acquired memory. This contribution is made as a "proof of concept" to the field of biological immune system simulation as a start of further research efforts in this direction. Many applications can potentially use our designed Neuro-Immune Network (NIN), especially in the area of autonomous robotics. We demonstrated the use of the designed NIN to control a robot arm in an unknown environment. As the system encounters new cases, it will increase its ability to deal with old and new situations encountered. This novel technique can be applied to many robotics applications in industry, where autonomous robots are required to have adaptive behavior in response to their environmental changes. Regarding future work, the use of VLSI neural networks to enhance the speed of the system for real time applications can be investigated along with possible methods of design and implementation of a similar VLSI chip for the AIN.Ph. D.
2
Jarne, Ornia Daniel. "Ant Colony Algorithms andits applications to Autonomous Agents Systems." Thesis, KTH, Optimeringslära och systemteori, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-217391.
Full textAbstract:
With the latest advancements in autonomous agents systems and technology, there is a growing interest in developing control algorithms and methods to coordinate large numbers of robotic entities. Following this line of work, the use of biologically inspired algorithms based on swarm emerging behaviour presents some really interesting properties for controlling multiple agents. They rely on very simple instructions and communications to develop a coordinated structure in the system. Particularly, this master thesis focuses on the study of Ant Colony algorithms based on stigmergy interaction to coordinate agents and perform a certain task. The first part focuses on the theoretical background and algorithm convergence proof, while the second part consists of experimental simulations and results. For this, some metric parameters have been developed and found to be especially useful in the study of a simple path planning test case. The main concept developed in this work is an adaptation of Shannon Entropy that measures uniformity and order in the system and the weighted graph. This parameter has been used to study the performance and results of an autonomous agent system based on Ant Colony algorithms. Finally, this control algorithm has been modified to develop an event-triggered control scheme. Using the properties of the weighted graph (Entropy) and the sensing of the agents, a decentralized event-triggered method has been implemented and tested, and has been found to increase efficiency in the usage of system resources.Med den senaste tidens utveckling inom autonoma agentsystem och teknologier, finns ett ökat intresse för utveckling av styralgoritmer och metoder för att koordinera stora mängder robotenheter. Inom detta område visar användandet av biologiskt inspirerade algoritmer, baserade på naturliga svärmbeteenden, intressanta egenskaper som kan utnyttjas i styrandet av system som innefattar ett flertal agenter. Dessa är uppbyggda av simpla instruktioner och kommunikationsmedel för att tillgodose struktur i systemet. I synnerhet fokuserar detta masterexamensarbete på studier av Ant Colony-algoritmer, baserade på stigmergy-interaktion för att koordinera enheter och få dem att utföra specifika uppgifter. Den första delen behandlar den teoretiska bakgrunden och konvergensbevis medan den andra delen i huvudsak består av experimentella simuleringar samt resultat. Till detta ändamål har metriska parametrar utvecklats, vilka ansågs särskilt användbara när planeringen av en enkel bana studerades. Huvudkonceptet som utvecklats i detta arbete är en tillämpning av Shannon- Entropi, vilket mäter enhetlighet och ordning i ett system samt den viktade grafen. Denna parameter har använts för att studera prestandan och resultaten hos ett autonomt agentsystem baserat på Ant Colony-algoritmer. Slutligen har denna styralgoritm modifierats för att utveckla ett händelsestyrt styrschema. Genom att använda egenskaperna hos den viktade grafen (entropi) tillsammans med sensorsystemet hos agentenheterna, så har en decentraliserad händelsestyrd metod implementerats, testats och visat sig ge ökad effektivitet gällande utnyttjandet av systemresurser.
3
AL-Buraiki, Omar S. M. "Specialized Agents Task Allocation in Autonomous Multi-Robot Systems." Thesis, Université d'Ottawa / University of Ottawa, 2020. http://hdl.handle.net/10393/41504.
Full textAbstract:
With the promise to shape the future of industry, multi-agent robotic technologies have the potential to change many aspects of daily life. Over the coming decade, they are expected to impact transportation systems, military applications such as reconnaissance and surveillance, search-and-rescue operations, or space missions, as well as provide support to emergency first responders.
Motivated by the latest developments in the field of robotics, this thesis contributes to the evolution of the future generation of multi-agent robotic systems as they become smarter, more accurate, and diversified in terms of applications. But in order to achieve these goals, the individual agents forming cooperative robotic systems need to be specialized in what they can accomplish, while ensuring accuracy and preserving the ability to perform diverse tasks.
This thesis addresses the problem of task allocation in swarm robotics in the specific context where specialized capabilities of the individual agents are considered. Based on the assumption that each individual agent possesses specialized functional capabilities and that the expected tasks, which are distributed in the surrounding environment, impose specific requirements, the proposed task allocation mechanisms are formulated in two different spaces. First, a rudimentary form of the team members’ specialization is formulated as a cooperative control problem embedded in the agents’ dynamics control space. Second, an advanced formulation of agents’ specialization is defined to estimate the individual agents’ task allocation probabilities in a dedicated specialization space, which represents the core contribution of this thesis to the advancement and practice in the area of swarm robotics.
The original task allocation process formulated in the specialization space evolves through four stages of development. First, a task features recognition stage is conceptually introduced to leverage the output of a sensing layer embedded in robotic agents to drive the proposed task allocation scheme. Second, a matching scheme is developed to best match each agent’s specialized capabilities with the corresponding detected tasks. At this stage, a general binary definition of agents’ specialization serves as the basis for task-agent association. Third, the task-agent matching scheme is expanded to an innovative probabilistic specialty-based task-agent allocation framework to generalize the concept and exploit the potential of agents’ specialization consideration. Fourth, the general framework is further refined with a modulated definition of the agents’ specialization based on their mechanical, physical structure, and embedded resources. The original framework is extended and a prioritization layer is also introduced to improve the system’s response to complex tasks that are characterized based on the recognition of multiple classes.
Experimental validation of the proposed specialty-based task allocation approach is conducted in simulation and on real-world experiments, and the results are presented and discussed in light of potential applications to demonstrate the effectiveness and efficiency of the proposed framework.
4
Hess, Traci J. "A Study of Autonomous Agents in Decision Support Systems." Diss., Virginia Tech, 1998. http://hdl.handle.net/10919/11277.
Full textAbstract:
Software agents have been heralded as the most important emerging technology of the decade. As software development firms eagerly attempt to integrate these autonomous programs into their products, researchers attempt to define the concept of agency and to develop architectures that will improve agent capabilities. Decision Support System (DSS) researchers have been eager to integrate agents into their applications, and exploratory works in which agents have been used within a DSS have been documented. This dissertation attempts to further this exploration by studying the agent features and underlying architectures that can lead to the successful integration of agents in DSS.
This exploration is carried out in three parts. In the first part, a review of the relevant research streams is provided. The history and current status of software agents is first discussed. Similarly, a historical and current view of DSS research is provided. Lastly, a historical and tutorial-type of discussion is provided on the topic of Artificial Intelligence (AI) planning. This review of the relevant literature provides a general background for the conceptual analyses and implementations that are carried out in the next two sections.
In the second part, the literature on software agents is synthesized to develop a definition of agency applicable to DSS. Using this definition, an agent-integrated DSS that supports variance-analysis is designed and developed. Following this implementation, a general framework for agent-enabling DSS is suggested. The use of this framework promises to raise some DSS to a new level of capability whereby "what-if" systems are transformed into real-time, proactive systems.
The third part utilizes this general framework to agent-enable a corporate-planning system DSS and extends the framework in the second section through the introduction of an automated-planning agent. The agent uses AI planning to generate decision-making alternatives, providing a means to integrate and sequence the models in the DSS. The architecture used to support this planning agent is described. This new kind of DSS enables not only the monitoring of goals, but also the maintenance of these goals through agent-generated plans.
The conclusion summarizes the contributions of this work and outlines in considerable detail potential research opportunities in the realm of software agents, DSS, and planning.Ph. D.
5
Faratin, Peyman. "Automated service negotiation between autonomous computational agents." Thesis, Queen Mary, University of London, 2000. http://qmro.qmul.ac.uk/xmlui/handle/123456789/28945.
Full textAbstract:
Multi-agent systems are a new computational approach for solving real world, dynamic and open system problems. Problems are conceptualized as a collection of decentralised autonomous agents that collaborate to reach the overall solution. Because of the agents autonomy, their limited rationality, and the distributed nature of most real world problems, the key issue in multi-agent system research is how to model interactions between agents. Negotiation models have emerged as suitable candidates to solve this interaction problem due to their decentralised nature, emphasis on mutual selection of an action, and the prevalence of negotiation in real social systems. The central problem addressed in this thesis is the design and engineering of a negotiation model for autonomous agents for sharing tasks and/or resources. To solve this problem a negotiation protocol and a set of deliberation mechanisms are presented which together coordinate the actions of a multiple agent system. In more detail, the negotiation protocol constrains the action selection problem solving of the agents through the use of normative rules of interaction. These rules temporally order, according to the agents' roles, communication utterances by specifying both who can say what, as well as when. Specifically, the presented protocol is a repeated, sequential model where offers are iteratively exchanged. Under this protocol, agents are assumed to be fully committed to their utterances and utterances are private between the two agents. The protocol is distributed, symmetric, supports bi and/or multi-agent negotiation as well as distributive and integrative negotiation. In addition to coordinating the agent interactions through normative rules, a set of mechanisms are presented that coordinate the deliberation process of the agents during the ongoing negotiation. Whereas the protocol normatively describes the orderings of actions, the mechanisms describe the possible set of agent strategies in using the protocol. These strategies are captured by a negotiation architecture that is composed of responsive and deliberative decision mechanisms. Decision making with the former mechanism is based on a linear combination of simple functions called tactics, which manipulate the utility of deals. The latter mechanisms are subdivided into trade-off and issue manipulation mechanisms. The trade-off mechanism generates offers that manipulate the value, rather than the overall utility, of the offer. The issue manipulation mechanism aims to increase the likelihood of an agreement by adding and removing issues into the negotiation set. When taken together, these mechanisms represent a continuum of possible decision making capabilities: ranging from behaviours that exhibit greater awareness of environmental resources and less to solution quality, to behaviours that attempt to acquire a given solution quality independently of the resource consumption. The protocol and mechanisms are empirically evaluated and have been applied to real world task distribution problems in the domains of business process management and telecommunication management. The main contribution and novelty of this research are: i) a domain independent computational model of negotiation that agents can use to support a wide variety of decision making strategies, ii) an empirical evaluation of the negotiation model for a given agent architecture in a number of different negotiation environments, and iii) the application of the developed model to a number of target domains. An increased strategy set is needed because the developed protocol is less restrictive and less constrained than the traditional ones, thus supporting development of strategic interaction models that belong more to open systems. Furthermore, because of the combination of the large number of environmental possibilities and the size of the set of possible strategies, the model has been empirically investigated to evaluate the success of strategies in different environments. These experiments have facilitated the development of general guidelines that can be used by designers interested in developing strategic negotiating agents. The developed model is grounded from the requirement considerations from both the business process management and telecommunication application domains. It has also been successfully applied to five other real world scenarios.
6
Giansiracusa, Michelangelo Antonio. "A secure infrastructural strategy for safe autonomous mobile agents." Thesis, Queensland University of Technology, 2005. https://eprints.qut.edu.au/16052/1/Michaelangelo_Giansiracusa_Thesis.pdf.
Full textAbstract:
Portable languages and distributed paradigms have driven a wave of new applications and processing models. One of the most promising, certainly from its early marketing, but disappointing (from its limited uptake)is the mobile agent execution and data processing model. Mobile agents are autonomous programs which can move around a heterogeneous network such as the Internet, crossing through a number of different security domains, and perform some work at each visited destination as partial completion of a mission for their agent user.
Despite their promise as a technology and paradigm to drive global electronic services (i.e.any Internet-driven-and-delivered service, not solely e-commerce related activities), their up take on the Internet has been very limited. Chief among the reasons for the paradigm's practical under-achievement is there is no ubiquitous frame work for using Internet mobile agents, and non-trivial security concerns abound for the two major stake holders (mobile agent users and mobile agent platform owners).
While both stake holders have security concerns with the dangers of the mobile agent processing model, most investigators in the field are of the opinion that protecting mobile agents from malicious agent platforms is more problematic than protecting agent platforms from malicious mobile agents. Traditional cryptographic mechanisms are not well-suited to counter the bulk of the threats associated with the mobile agent paradigm due to the untrusted hosting of an agent and its intended autonomous, flexible movement and processing.
In our investigation, we identified that the large majority of the research undertaken on mobile agent security to date has taken a micro-level perspective. By this we mean research focused solely on either of the two major stakeholders, and even then often only on improving measures to address one security issue dear to the stake holder - for example mobile agent privacy (for agent users) or access control to platform resources (for mobile agent platform owners).
We decided to take a more encompassing, higher-level approach in tackling mobile agent security issues. In this endeavour, we developed the beginnings of an infrastructural-approach to not only reduce the security concerns of both major stakeholders, but bring them transparently to a working relationship. Strategic utilisation of both existing distributed system trusted-third parties (TTPs) and novel mobile agent paradigm-specific TTPs are fundamental in the infrastructural framework we have devised.
Besides designing an application and language independent frame work for supporting a large-scale Internet mobile agent network, our Mobile Agent Secure Hub Infrastructure (MASHIn) proposal encompasses support for flexible access control to agent platform resources. A reliable means to track the location and processing times of autonomous Internet mobile agents is discussed, withfault-tolerant handling support to work around unexpected processing delays. Secure,highly-effective (incomparison to existing mechanisms) strategies for providing mobile agent privacy, execution integrity, and stake holder confidence scores were devised - all which fit comfortably within the MASHIn framework. We have deliberately considered the interests - withoutbias -of both stake holders when designing our solutions.
In relation to mobile agent execution integrity, we devised a new criteria for assessing the robustness of existing execution integrity schemes. Whilst none of the existing schemes analysed met a large number of our desired properties for a robust scheme, we identified that the objectives of Hohl's reference states scheme were most admirable - particularly real - time in - mission execution integrity checking. Subsequently, we revised Hohl's reference states protocols to fit in the MASHIn framework, and were able to overcome not only the two major limitations identified in his scheme, but also meet all of our desired properties for a robust execution integrity scheme (given an acceptable decrease in processing effiency).
The MASHIn offers a promising new perspective for future mobile agent security research and indeed a new frame work for enabling safe and autonomous Internet mobile agents. Just as an economy cannot thrive without diligent care given to micro and macro-level issues, we do not see the security prospects of mobile agents (and ultimately the prospects of the mobile agent paradigm) advancing without diligent research on both levels.
7
Giansiracusa, Michelangelo Antonio. "A Secure Infrastructural Strategy for Safe Autonomous Mobile Agents." Queensland University of Technology, 2005. http://eprints.qut.edu.au/16052/.
Full textAbstract:
Portable languages and distributed paradigms have driven a wave of new applications and processing models. One of the most promising, certainly from its early marketing, but disappointing (from its limited uptake)is the mobile agent execution and data processing model. Mobile agents are autonomous programs which can move around a heterogeneous network such as the Internet, crossing through a number of different security domains, and perform some work at each visited destination as partial completion of a mission for their agent user. Despite their promise as a technology and paradigm to drive global electronic services (i.e.any Internet-driven-and-delivered service, not solely e-commerce related activities), their up take on the Internet has been very limited. Chief among the reasons for the paradigm's practical under-achievement is there is no ubiquitous frame work for using Internet mobile agents, and non-trivial security concerns abound for the two major stake holders (mobile agent users and mobile agent platform owners). While both stake holders have security concerns with the dangers of the mobile agent processing model, most investigators in the field are of the opinion that protecting mobile agents from malicious agent platforms is more problematic than protecting agent platforms from malicious mobile agents. Traditional cryptographic mechanisms are not well-suited to counter the bulk of the threats associated with the mobile agent paradigm due to the untrusted hosting of an agent and its intended autonomous, flexible movement and processing. In our investigation, we identified that the large majority of the research undertaken on mobile agent security to date has taken a micro-level perspective. By this we mean research focused solely on either of the two major stakeholders, and even then often only on improving measures to address one security issue dear to the stake holder - for example mobile agent privacy (for agent users) or access control to platform resources (for mobile agent platform owners). We decided to take a more encompassing, higher-level approach in tackling mobile agent security issues. In this endeavour, we developed the beginnings of an infrastructural-approach to not only reduce the security concerns of both major stakeholders, but bring them transparently to a working relationship. Strategic utilisation of both existing distributed system trusted-third parties (TTPs) and novel mobile agent paradigm-specific TTPs are fundamental in the infrastructural framework we have devised. Besides designing an application and language independent frame work for supporting a large-scale Internet mobile agent network, our Mobile Agent Secure Hub Infrastructure (MASHIn) proposal encompasses support for flexible access control to agent platform resources. A reliable means to track the location and processing times of autonomous Internet mobile agents is discussed, withfault-tolerant handling support to work around unexpected processing delays. Secure,highly-effective (incomparison to existing mechanisms) strategies for providing mobile agent privacy, execution integrity, and stake holder confidence scores were devised - all which fit comfortably within the MASHIn framework. We have deliberately considered the interests - withoutbias -of both stake holders when designing our solutions. In relation to mobile agent execution integrity, we devised a new criteria for assessing the robustness of existing execution integrity schemes. Whilst none of the existing schemes analysed met a large number of our desired properties for a robust scheme, we identified that the objectives of Hohl's reference states scheme were most admirable - particularly real - time in - mission execution integrity checking. Subsequently, we revised Hohl's reference states protocols to fit in the MASHIn framework, and were able to overcome not only the two major limitations identified in his scheme, but also meet all of our desired properties for a robust execution integrity scheme (given an acceptable decrease in processing effiency). The MASHIn offers a promising new perspective for future mobile agent security research and indeed a new frame work for enabling safe and autonomous Internet mobile agents. Just as an economy cannot thrive without diligent care given to micro and macro-level issues, we do not see the security prospects of mobile agents (and ultimately the prospects of the mobile agent paradigm) advancing without diligent research on both levels.
8
Abu, Bakar Badril. "Autonomous multi-agent reconfigurable control systems." Thesis, University of Southampton, 2013. https://eprints.soton.ac.uk/351346/.
Full textAbstract:
This thesis is an investigation of methods and architectures for autonomous multi-agent reconfigurable controllers. As part of the analysis two components are looked at: the fault detection and diagnosis (FDD) component and the controller reconfiguration (CR) component. The FDD component detects and diagnoses faults. The CR component on the other hand, adapts or changes the control architecture to accommodate the fault. The problem is to synchronize or integrate these two components in the overall structure of a control system. A novel approach is proposed. A multiagent architecture is used to interface between the two components. This method allows the system to be viewed as a modular structure. Three types of agent are defined. A planner agent Ap, a monitor agent Am and a control agent Ac. The monitor agent takes the role of the FDD component. The planner and control agents on the other hand take the roles of CR component. The planner decides which controller to use and passes it on to Ac. It also decides on the parameter settings of the system and changes it accordingly. It belongs to the reactive agent category. The planner agent's internal architecture maps its sensor data directly to actions using a pre-set rule based conditional logic. It was decided that this architecture would reduce the overall complexity of the system. The monitor agent Am belongs to the learning agent category. It uses an algorithm called adaptive resonance theory neural network or ART-NN to autonomously categorize system faults. Am then informs the other agents of the fault status. ART-NN was chosen due to the fact that it does not need to be trained with sample data and learns to categorize data patterns on the fly. This allows Am to detect unmodelled system faults. The control agent Ac also belongs to the learning agent category. It uses a multiagent reinforcement learning algorithm to learn a controller for the system at hand. Once a suitable controller has been learnt, the parameters of the controller are passed to Ap for it to be stored in its memory and learning is terminated. During control execution mode, controller parameters are sent to Ac from Ap. The novel approach is demonstrated on a case study. Our laboratory-built 4-wheeled skid-steering vehicle complete with sensors is designed as a way of demonstration. Several faults are simulated and the response of the demo system is analyzed.
9
LIMA, Allan Diego Silva. "FAct: Um framework para a construção de sistemas multiatores." Universidade Federal de Pernambuco, 2009. https://repositorio.ufpe.br/handle/123456789/1804.
Full textAbstract:
Made available in DSpace on 2014-06-12T15:52:31Z (GMT). No. of bitstreams: 1
license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5)
Previous issue date: 2009Atores Sintéticos são agentes inteligentes que possuem personalidade, atuam em ambientes multimídias ou virtuais e são representados graficamente por avatares. Estas entidades são utilizadas em sistemas de simuladores como forma de enriquecer a interação entre a aplicação e seus usuários, proporcionando assim aumento da credibilidade do projeto. Com a sua popularização sugiram vários projetos que os utilizam. Estes projetos têm diversos aspectos em comum. Por exemplo, neles seus atores se comunicam e possuem modelos de personalidade. Contudo, apesar das similaridades os projetos encontrados na literatura foram implementados de forma independente. Ou seja, tiveram seu código fonte desenvolvido do zero. Porém, no âmbito dos sistemas multiagentes tal problema não ocorre devido à existência de diversos frameworks multiagentes que agrupam as funcionalidades comuns a tais sistemas, fazendo com que o desenvolvedor implemente apenas o que é relativo ao seu contexto de simulação. Porém, estes frameworks não são utilizados em sistemas multiarores, pois não suportam as peculiaridades dos sistemas multiatores. Buscando solucionar esse problema, este trabalho apresenta o FAct (Framework for Actors), um projeto criado especificamente para auxiliar na construção sistemas multiatores. Ele focado nas características peculiares destes sistemas e tem como principal objetivo reduzir o custo e tempo de desenvolvimento para os projetos baseados nesta tecnologia. Como forma de exemplificar o uso do FAct e avaliar o seu impacto no desenvolvimento de simuladores multiatores, serão apresentados dois simuladores implementados com base no framework
10
Lutzhöft, Margareta. "Self-organised communication in autonomous agents: A critical evaluation of artificial life models." Thesis, University of Skövde, Department of Computer Science, 2000. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-485.
Full textAbstract:
This dissertation aims to provide a critical evaluation of artificial life (A-Life) models of communication in autonomous agents. In particular the focus will be on the issue of self-organisation, which is often argued to be one of the characteristic features distinguishing A-life from other approaches. To ground the arguments, a background of the study of communication within artificial intelligence is provided. This is followed by a comprehensive review of A-Life research on communication between autonomous agents, which is evaluated by breaking down self-organisation into the following sub-questions. Is communication self-organised or hard-coded? What do signals mean to the agents, and how should an external examiner interpret them? Is there any spatial or temporal displacement, or do agents only communicate about their present situation? It is shown that there is very little self-organised communication, as yet, when examined on these grounds, and that most models only look at communication as relatively independent from other behaviours. As a conclusion, it is suggested to use integrated co-evolution of behaviours, including communication, in the spirit of the enactive cognitive science paradigm, and by using incremental evolution combined with learning.
11
Collins, N. M. "Towards autonomous agents for live computer music : realtime machine listening and interactive music systems." Thesis, University of Cambridge, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.597873.
Full textAbstract:
This thesis will describe a set of interactive systems developed for a range of musical styles and instruments, all of which attempt to participate in a concert by means of audio signal analysis alone. Machine listening, being the simulation of human peripheral auditory abilities, and the hypothetical modelling of central auditory and cognitive processes, is utilised in these systems to track musical activity. Whereas much of this modelling is inspired by a bid to emulate human abilities, strategies diverging from plausible human physiological mechanisms are often employed, leading to matching capabilities which exceed or differ from the human counterparts. Technology is described which detects events from an audio stream, further analysing the discovered events (typically notes) for perceptual features of loudness, pitch, attack time and timbre. In order to exploit processes that underlie common musical practice, beat tracking is investigated, allowing the inference of metrical structure which can act as a co-ordinative framework for interaction. Psychological experiments into human judgement of perceptual attack time and beat tracking to ecologically valid stimuli clarify the parameters and constructs that should most appropriately be instantiated in the computational systems. All the technology produced is intended for the demanding environment of realtime concert use. In particular, an algorithmic audio splicing and analysis library called BBCut2 is described, designed with appropriate processing and scheduling facilities for realtime operation. Proceeding to outlines of compositional applications, novel interactive music systems are introduced which have been tested in real concerts. These are evaluated by interviews with the musicians who performed with them, and an assessment of their claims to agency in the sense of ‘autonomous agents’. The thesis closes by considering all that has been built, and the possibilities for future advances allied to artificial intelligence and signal processing technology.
12
Magg, Sven. "Self-organised task differentiation in homogeneous and heterogeneous groups of autonomous agents." Thesis, University of Hertfordshire, 2012. http://hdl.handle.net/2299/9038.
Full textAbstract:
The field of swarm robotics has been growing fast over the last few years. Using a swarm of simple and cheap robots has advantages in various tasks. Apart from performance gains on tasks that allow for parallel execution, simple robots can also be smaller, enabling them to reach areas that can not be accessed by a larger, more complex robot. Their ability to cooperate means they can execute complex tasks while offering self-organised adaptation to changing environments and robustness due to redundancy. In order to keep individual robots simple, a control algorithm has to keep expensive communication to a minimum and has to be able to act on little information to keep the amount of sensors down. The number of sensors and actuators can be reduced even more when necessary capabilities are spread out over different agents that then combine them by cooperating. Self-organised differentiation within these heterogeneous groups has to take the individual abilities of agents into account to improve group performance. In this thesis it is shown that a homogeneous group of versatile agents can not be easily replaced by a heterogeneous group, by separating the abilities of the versatile agents into several specialists. It is shown that no composition of those specialists produces the same outcome as a homogeneous group on a clustering task. In the second part of this work, an adaptation mechanism for a group of foragers introduced by Labella et al. (2004) is analysed in more detail. It does not require communication and needs only the information on individual success or failure. The algorithm leads to self-organised regulation of group activity depending on object availability in the environment by adjusting resting times in a base. A possible variation of this algorithm is introduced which replaces the probabilistic mechanism with which agents determine to leave the base. It is demonstrated that a direct calculation of the resting times does not lead to differences in terms of differentiation and speed of adaptation. After investigating effects of different parameters on the system, it is shown that there is no efficiency increase in static environments with constant object density when using a homogeneous group of agents. Efficiency gains can nevertheless be achieved in dynamic environments. The algorithm was also reported to lead to higher activity of agents which have higher performance. It is shown that this leads to efficiency gains in heterogeneous groups in static and dynamic environments.
13
Hurt, David. "An Empirical Evaluation of Communication and Coordination Effectiveness in Autonomous Reactive Multiagent Systems." Thesis, University of North Texas, 2005. https://digital.library.unt.edu/ark:/67531/metadc4770/.
Full textAbstract:
This thesis describes experiments designed to measure the effect of collaborative communication on task performance of a multiagent system. A discrete event simulation was developed to model a multi-agent system completing a task to find and collect food resources, with the ability to substitute various communication and coordination methods. Experiments were conducted to find the effects of the various communication methods on completion of the task to find and harvest the food resources. Results show that communication decreases the time required to complete the task. However, all communication methods do not fare equally well. In particular, results indicate that the communication model of the bee is a particularly effective method of agent communication and collaboration. Furthermore, results indicate that direct communication with additional information content provides better completion results. Cost-benefit models show some conflicting information, indicating that the increased performance may not offset the additional cost of achieving that performance.
14
Evans, Katherine. "The Implementation of Ethical Decision Procedures in Autonomous Systems : the Case of the Autonomous Vehicle." Thesis, Sorbonne université, 2021. http://www.theses.fr/2021SORUL003.
Full textAbstract:
Les problèmes éthiques liés à l’arrivée de formes d’intelligence artificielles différentes a sollicité beaucoup d’attention aussi bien académique que publique. Cependant, ces inquiétudes se concentrent sur un problème particulier : comment assurer que les décisions prises par les agents artificiels comme des voitures autonomes ne nuisent pas aux êtres humains présents dans leur environnement ? Cette question a incité la création de ceux qui sont communément appelés les agents moraux artificiels dans la littérature, la prise de décision desquels est contrainte par une moralité artificielle : un système de principes normatifs implémenté dans le processus de raisonnement de la machine. A ce jour, la forme que prend cette moralité artificielle relève de deux approches différentes : soit une forme maximalement éthique, qui dépend de l’implémentation stricte des théories morales préexistantes comme la déontologie Kantienne ou l’Utilitarisme, soit une forme minimaliste, qui applique des techniques de l’IA stochastique à l’analyse et agrégation de données portant sur les préférences morales d’une population, afin d’en tirer des principes généraux mobilisés ensuite dans la prise de décision des machines. Prises individuellement, aucune des deux approches n’arrivent à pondérer l’importance des contraintes morales avec la pertinence de l’acceptabilité publique des agents moraux artificiels. Nous proposons une approche alternative à la moralité artificielle, la théorie des valences éthiques, qui s’efforce d’accommoder ce genre de pondération, et nous l’appliquons au cas du véhicule autonomeThe ethics of emerging forms of artificial intelligence has become a prolific subject in both academic and public spheres. A great deal of these concerns flow from the need to ensure that these technologies do not cause harm—physical, emotional or otherwise—to the human agents with which they will interact. In the literature, this challenge has been met with the creation of artificial moral agents: embodied or virtual forms of artificial intelligence whose decision procedures are constrained by explicit normative principles, requiring the implementation of what is commonly called artificial morality into these agents. To date, the types of reasoning structures and principles which inform artificial morality have been of two kinds: first, an ethically maximal vision of artificial morality which relies on the strict implementation of traditional moral theories such as Kantian deontology or Utilitarianism, and second, a more minimalist vision which applies stochastic AI techniques to large data sets of human moral preferences so as to illicit or intuit general principles and preferences for the design of artificial morality. Taken individually, each approach is unable to fully answer the challenge of producing inoffensive behavior in artificial moral agents, most especially since both forms are unable to strike a balance between the ideal set of constraints which morality imposes on one hand, and the types of constraints public acceptability imposes, on the other. We provide an alternative approach to the design of artificial morality, the Ethical Valence Theory, whose purpose is to accommodate this balance, and apply this approach to the case of autonomous vehicles
15
Estgren, Martin. "Lightweight User Agents." Thesis, Linköpings universitet, Artificiell intelligens och integrerad datorsystem, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-129909.
Full textAbstract:
The unit for information security and IT architecture at The Swedish Defence Research Agency (FOI) conducts work with a cyber range called CRATE (Cyber Range and Training Environment). Currently, simulation of user activity involves scripts inside the simulated network. This solution is not ideal because of the traces it leaves in the system and the general lack of standardised GUI API between different operating systems. FOI are interested in testing the use of artificial user agent located outside the virtual environment using computer vision and the virtualisation API to execute actions and extract information from the system. This paper focuses on analysing the reliability of template matching, a computer vision algorithm used to localise objects in images using already identified images of said object as templates. The analysis will evaluate both the reliability of localising objects and the algorithms ability to correctly identify if an object is present in the virtual environment. Analysis of template matching is performed by first creating a prototype of the agent's sensory system and then simulate scenarios which the agent might encounter. By simulating the environment, testing parameters can be manipulated and monitored in a reliable way. The parameters manipulated involves both the amount and type of image noise in the template and screenshot, the agent’s discrimination threshold for what constitutes a positive match, and information about the template such as template generality. This paper presents the performance and reliability of the agent in regards to what type of image noise affects the result, the amount of correctly identified objects given different discrimination thresholds, and computational time of template matching when different image filters are applied. Furthermore the best cases for each study are presented as comparison for the other results. In the end of the thesis we present how for screenshots with objects very similar to the templates used by the agent, template matching can result in a high degree of accuracy in both object localization and object identification and that a small reduction of similarity between template and screenshot to reduce the agent's ability to reliably identifying specific objects in the environment.
16
Luotsinen, Linus Jan. "AUTONOMOUS ENVIRONMENTAL MAPPING IN MULTI-AGENT UAV SYSTEMS." Master's thesis, University of Central Florida, 2004. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/4421.
Full textAbstract:
UAV units are by many researchers and aviation specialists considered the future and cutting edge of modern flight technology. This thesis discusses methods for efficient autonomous environmental mapping in a multi-agent domain. An algorithm that emphasizes on team work by sharing the agents local map information and exploration intentions is presented as a solution to the mapping problem. General theories on how to model and implement rational autonomous behaviour for UAV agents are presented. Three different human and tactical behaviour modeling techniques are evaluated. The author found the CxBR paradigm to be the most interesting approach. Also, in order to test and quantify the theories presented in this thesis a simulation environment was developed. This simulation software allows for UAV agents to operate in a visual 3-D environment with mountains, other various terrain types, danger points and enemies to model unexpected events.M.S.
Department of Electrical and Computer Engineering
Engineering and Computer Science;
Electrical and Computer Engineering
17
Jimenez-Romero, Cristian. "A heterosynaptic spiking neural system for the development of autonomous agents." Thesis, Open University, 2017. http://oro.open.ac.uk/48888/.
Full textAbstract:
Artificial neural systems for computation were first proposed three quarters of a century ago and the concepts developed by the pioneers still shape the field today. The first generation of neural systems was developed in the nineteen forties in the context of analogue electronics and the theoretical research in logic and mathematics that led to the first digital computers in nineteen forties and fifties. The second generation of neural systems implemented on digital computers was born in the nineteen fifties and great progress was made in the subsequent half century with neural networks being applied to many problems in pattern recognition and machine learning. Through this history there has been an interplay between biologically inspired neural systems and their implementation by engineers on digital machines. This thesis concerns the third generation of neural networks, Spiking Neural Networks, which is making possible the creation of new kinds of brain inspired computing architectures that offer the potential to increase the level of realism and sophistication in terms of autonomous machine behaviour and cognitive computing. This thesis presents the development and demonstration of a new theoretical architecture for third generation neural systems, the Integrate-and-Fire based Spiking Neural Model with extended Neuro-modulated Spike Timing Dependent Plasticity capabilities. This proposed architecture overcomes the limitation of the homosynaptic architecture underlying existing implementations of spiking neural networks that it lacks a natural spike timing dependent plasticity regulation mechanism, and this results in ‘run away’ dynamics. To overcome this ad hoc procedures have been implemented to overcome the ‘run away’ dynamics that emerge from the use of spike timing dependent plasticity among other hebbian-based plasticity rules. The new heterosynaptic architecture presented, explicitly abstracts the modulation of complex biochemical mechanisms into a simplified mechanism that is suitable for the engineering of artificial systems with low computational complexity. Neurons work by receiving input signals from other neurons through synapses. The difference between homosynaptic and heterosynaptic plasticity is that, in the former the change in the properties of a synapse (e.g. synaptic efficacy) depends on the point to point activity in either of the sending and receiving neurons, in contrast for heterosynaptic plasticity the change in the properties of a synapse can be elicited by neurons that are not necessary presynaptic or postsynaptic to the synapse in question. The new architecture is tested by a number of implementations in simulated and real environments. This includes experiments with a simulation environment implemented in Netlogo, and an implementation using Lego Mindstorms as the physical robot platform. These experiments demonstrate the problems with the traditional Spike timing dependent plasticity homosynaptic architecture and how the new heterosynaptic approach can overcome them. It is concluded that the new theoretical architecture provides a natural, theoretically sound, and practical new direction for research into the role of modulatory neural systems applied to spiking neural networks.
18
Szwaykowska, Klementyna. "Controlled Lagrangian particle tracking: analyzing the predictability of trajectories of autonomous agents in ocean flows." Diss., Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/50357.
Full textAbstract:
Use of model-based path planning and navigation is a common strategy in mobile robotics. However, navigation performance may degrade in complex, time-varying environments under model uncertainty because of loss of prediction ability for the robot state over time. Exploration and monitoring of ocean regions using autonomous marine robots is a prime example of an application where use of environmental models can have great benefits in navigation capability. Yet, in spite of recent improvements in ocean modeling, errors in model-based flow forecasts can still significantly affect the accuracy of predictions of robot positions over time, leading to impaired path-following performance. In developing new autonomous navigation strategies, it is important to have a quantitative understanding of error in predicted robot position under different flow conditions and control strategies.
The main contributions of this thesis include development of an analytical model for the growth of error in predicted robot position over time and theoretical derivation of bounds on the error growth, where error can be attributed to drift caused by unmodeled components of ocean flow. Unlike most previous works, this work explicitly includes spatial structure of unmodeled flow components in the proposed error growth model. It is shown that, for a robot operating under flow-canceling control in a static flow field with stochastic errors in flow values returned at ocean model gridpoints, the error growth is initially rapid, but slows when it reaches a value of approximately twice the ocean model gridsize. Theoretical values for mean and variance of error over time under a station-keeping feedback control strategy and time-varying flow fields are computed. Growth of error in predicted vehicle position is modeled for ocean models whose flow forecasts include errors with large spatial scales. Results are verified using data from several extended field deployments of Slocum autonomous underwater gliders, in Monterey Bay, CA in 2006, and in Long Bay, SC in 2012 and 2013.
19
Assaad, Mohamad Ali. "An overview on systems of systems control : general discussions and application to multiple autonomous vehicles." Thesis, Compiègne, 2019. http://www.theses.fr/2019COMP2466/document.
Full textAbstract:
La thèse porte sur le contrôle des systèmes de systèmes (SdS) et, sur la manière de construire des SdS adaptables et fiables. Ce travail fait partie du laboratoire d’excellence Labex MS2T sur le développement des SdS technologiques. Les SdS sont des systèmes complexes constitués de plusieurs systèmes indépendants qui fonctionnent ensemble pour atteindre un objectif commun. L’ingénierie des SdS est une approche qui se concentre sur la manière de construire et de concevoir des SdS fiables capables de s’adapter à l’environnement dynamique dans lequel ils évoluent. Compte tenu de l’importance du contrôle des systèmes constituants (SC) pour atteindre les objectifs du SdS , la première partie de cette thèse a consisté en une étude bibliographique sur le sujet du contrôle des SdS. Certaines méthodes de contrôle existent pour les systèmes à grande échelle et les systèmes multi-agents, à savoir, le contrôle hiérarchique, distribué et décentralisé peuvent être utiles et sont utilisés pour contrôler les SdS. Ces méthodes ne conviennent pas pour contrôler un SdS dans sa globalité et son évolution, en raison de l’indépendance de leur SC ; alors que les “frameworks” multi-vues conviennent mieux à cet objectif. Une approche de ”framework” générale est proposée pour modéliser et gérer les interactions entre les SC dans un SdS. La deuxième partie de notre travail a consisté à contribuer aux systèmes de transport intelligent. À cette fin, nous avons proposé le gestionnaire de manœuvres coopératives pour les véhicules autonomes (CMMAV), un “framework” qui guide le développement des applications coopératives dans les véhicules autonomes. Pour valider le CMMAV, nous avons développé le gestionnaire de manœuvres latérales coopératives (CLMM), une application sur les véhicules autonomes qui permet d’échanger des demandes afin de coopérer lors de manœuvres de dépassement sur autoroute. Cette application a été validée par des scénarios formels, des simulations informatiques, et testée sur les véhicules autonomes du projet Robotex au laboratoire HeudiasycThis thesis focuses on System of Systems (SoS) control, and how to build adaptable and reliable SoS. This work is part of the Labex MS2T laboratory of excellence on technological SoS development. SoS are complex systems that consist of multiple independent systems that work together to achieve a common goal. SoS Engineering is an approach that focuses on how to build and design reliable SoS that can adapt to the dynamic environment in which they operate. Given the importance of controlling constituent systems (CS) in order to achieve SoS objectives, the first part of this thesis involved a literature study about the subject of SoS control. Some control methods exist for large-scale systems and multi-agent systems, namely, hierarchical, distributed, and decentralized control might be useful and are used to control SoS. These methods are not suitable for controlling SoS in its whole, because of the independence of their CS; whereas, multi-views frameworks are more suitable for this objective. A general framework approach is proposed to model and manage the interactions between CS in a SoS. The second part of our work consisted of contributing to Intelligent Transportation Systems. For this purpose, we have proposed the Cooperative Maneuvers Manager for Autonomous Vehicles (CMMAV), a framework that guides the development of cooperative applications in autonomous vehicles. To validate the CMMAV, we have developed the Cooperative Lateral Maneuvers Manager (CLMM), an application on the autonomous vehicles that enables equipped vehicles to exchange requests in order to cooperate during overtaking maneuvers on highways. It was validated by formal scenarios, computer simulations, and tested on the autonomous vehicles of the Equipex Robotex in Heudiasyc laboratory
20
Bakolas, Efstathios. "Optimal steering for kinematic vehicles with applications to spatially distributed agents." Diss., Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/42873.
Full textAbstract:
The recent technological advances in the field of autonomous vehicles have resulted in a growing impetus for researchers to improve the current framework of mission planning and execution within both the military and civilian contexts. Many recent efforts towards this direction emphasize the importance of replacing the so-called monolithic paradigm, where a mission is planned, monitored, and controlled by a unique global decision maker, with a network centric paradigm, where the same mission related tasks are performed by networks of interacting decision makers (autonomous vehicles). The interest in applications involving teams of autonomous vehicles is expected to significantly grow in the near future as new paradigms for their use are constantly being proposed for a diverse spectrum of real world applications.
One promising approach to extend available techniques for addressing problems involving a single autonomous vehicle to those involving teams of autonomous vehicles is to use the concept of Voronoi diagram as a means for reducing the complexity of the multi-vehicle problem. In particular, the Voronoi diagram provides a spatial partition of the environment the team of vehicles operate in, where each element of this partition is associated with a unique vehicle from the team. The partition induces, in turn, a graph abstraction of the operating space that is in a one-to-one correspondence with the network abstraction of the team of autonomous vehicles; a fact that can provide both conceptual and analytical advantages during mission planning and execution. In this dissertation, we propose the use of a new class of Voronoi-like partitioning schemes with respect to state-dependent proximity (pseudo-) metrics rather than the Euclidean distance or other generalized distance functions, which are typically used in the literature. An important nuance here is that, in contrast to the Euclidean distance, state-dependent metrics can succinctly capture system theoretic features of each vehicle from the team (e.g., vehicle kinematics), as well as the environment-vehicle interactions, which are induced, for example, by local winds/currents. We subsequently illustrate how the proposed concept of state-dependent Voronoi-like partition can induce local control schemes for problems involving networks of spatially distributed autonomous vehicles by examining different application scenarios.
21
Choi, J. "Model checking for decision making behaviour of heterogeneous multi-agent autonomous system." Thesis, Cranfield University, 2013. http://dspace.lib.cranfield.ac.uk/handle/1826/8031.
Full textAbstract:
An autonomous system has been widely applied for various civil/military research because of its versatile capability of understanding high-level intent and direction of a surrounding environment and targets of interest. However, as autonomous systems can be out of control to cause serious loss, injury, or death in the worst case, the verification of their functionalities has got increasing attention. For that reason, this study is focused on the verification of a heterogeneous multi-agent autonomous system. The thesis first presents an overview of formal methods, especially focuses on model checking for autonomous systems verification. Then, six case studies are presented to verify the decision making behaviours of multi-agent system using two basic scenarios: surveillance and convoy. The initial system considered in the surveillance mission consists of a ground control system and a micro aerial vehicle. Their decision-making behaviours are represented by means of Kripke model and computational tree logic is used to specify the properties of this system. For automatic verification, MCMAS (Model Checker for Multi-Agent Systems) is adopted due to its novel capability to accommodate the multi-agent system. After that, the initial system is extended to include a substitute micro aerial vehicle. These initial case studies are then further extended based on SEAS DTC exemplar 2 dealing with behaviours of convoy protection. This case study includes now a ground control system, an unmanned aerial vehicle, and an unmanned ground vehicle. The MCMAS successfully verifies the targeting behaviours of the team-level unmanned systems. Reversely, these verification results help retrospectively improve the design of decision-making algorithms by considering additional agents and behaviours during four steps of scenario modification. Consequently, the last scenario deals with the system composed of a ground control system, two unmanned aerial vehicles, and four unmanned ground vehicles with fault-tolerant and communications relay capabilities. In conclusion, this study demonstrates the feasibility of model checking algorithms as a verification tool of a multi-agent system in an initial design stage. Moreover, this research can be an important first step of the certification of multi-agent autonomous systems for the domains of robotics, aerospace and aeronautics.
22
Johansson, Linda. "Autonomous Systems in Society and War : Philosophical Inquiries." Doctoral thesis, KTH, Filosofi, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-127813.
Full textAbstract:
The overall aim of this thesis is to look at some philosophical issues surrounding autonomous systems in society and war. These issues can be divided into three main categories. The first, discussed in papers I and II, concerns ethical issues surrounding the use of autonomous systems – where the focus in this thesis is on military robots. The second issue, discussed in paper III, concerns how to make sure that advanced robots behave ethically adequate. The third issue, discussed in papers IV and V, has to do with agency and responsibility. Another issue, somewhat aside from the philosophical, has to do with coping with future technologies, and developing methods for dealing with potentially disruptive technologies. This is discussed in papers VI and VII. Paper I systemizes some ethical issues surrounding the use of UAVs in war, with the laws of war as a backdrop. It is suggested that the laws of war are too wide and might be interpreted differently depending on which normative moral theory is used. Paper II is about future, more advanced autonomous robots, and whether the use of such robots can undermine the justification for killing in war. The suggestion is that this justification is substantially undermined if robots are used to replace humans to a high extent. Papers I and II both suggest revisions or additions to the laws or war. Paper III provides a discussion on one normative moral theory – ethics of care – connected to care robots. The aim is twofold: first, to provide a plausible and ethically relevant interpretation of the key term care in ethics of care, and second, to discuss whether ethics of care may be a suitable theory to implement in care robots. Paper IV discusses robots connected to agency and responsibility, with a focus on consciousness. The paper has a functionalistic approach, and it is suggested that robots should be considered agents if they can behave as if they are, in a moral Turing test. Paper V is also about robots and agency, but with a focus on free will. The main question is whether robots can have free will in the same sense as we consider humans to have free will when holding them responsible for their actions in a court of law. It is argued that autonomy with respect to norms is crucial for the agency of robots. Paper VI investigates the assessment of socially disruptive technological change. The coevolution of society and potentially disruptive technolgies makes decision-guidance on such technologies difficult. Four basic principles are proposed for such decision guidance, involving interdisciplinary and participatory elements. Paper VII applies the results from paper VI – and a workshop – to autonomous systems, a potentially disruptive technology. A method for dealing with potentially disruptive technolgies is developed in the paper.QC 20130911
23
Olcay, Ertug [Verfasser], Boris [Akademischer Betreuer] Lohmann, Maruthi R. [Gutachter] Akella, and Boris [Gutachter] Lohmann. "Toward Control of Multi-Agent Systems: Cooperative Navigation of Autonomous Agents in Unknown Environments / Ertug Olcay ; Gutachter: Maruthi R. Akella, Boris Lohmann ; Betreuer: Boris Lohmann." München : Universitätsbibliothek der TU München, 2021. http://d-nb.info/1231434554/34.
Full text
24
Redmill, Keith Alan. "Automated vehicles : the nature and implementation of autonomous multi-agent systems /." The Ohio State University, 1998. http://rave.ohiolink.edu/etdc/view?acc_num=osu148795356777093.
Full text
25
Pavlic, Theodore Paul. "Design and Analysis of Optimal Task-Processing Agents." The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1281462093.
Full text
26
Santos, Vasco Pedro dos Anjos e. "DSAAR: distributed software architecture for autonomous robots." Master's thesis, FCT - UNL, 2009. http://hdl.handle.net/10362/1913.
Full textAbstract:
Dissertação apresentada na Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa para obtenção do grau de Mestre em Engenharia ElectrotécnicaThis dissertation presents a software architecture called the Distributed Software Architecture for Autonomous Robots (DSAAR), which is designed to provide the fast development and prototyping of multi-robot systems. The DSAAR building blocks allow engineers to focus on the behavioural model of robots and collectives. This architecture is of special interest in domains where several human, robot, and software agents have to interact continuously. Thus, fast prototyping and reusability is a must. DSAAR tries to cope with these requirements towards an advanced solution to the n-humans and m-robots problem with a set of design good practices and development tools. This dissertation will also focus on Human-Robot Interaction, mainly on the subject of teleoperation. In teleoperation human judgement is an integral part of the process, heavily influenced by the telemetry data received from the remote environment. So the speed in which commands are given and the telemetry data is received, is of crucial importance. Using the DSAAR architecture a teleoperation approach is proposed. This approach was designed to provide all entities present in the network a shared reality, where every entity is an information source in an approach similar to the distributed blackboard. This solution was designed to accomplish a real time response, as well as, the completest perception of the robots’ surroundings. Experimental results obtained with the physical robot suggest that the system is able to guarantee a close interaction between users and robot.
27
Tlig, Mohamed. "Coordination locale et optimisation distribuée du trafic de véhicules autonomes dans un réseau routier." Thesis, Université de Lorraine, 2015. http://www.theses.fr/2015LORR0049/document.
Full textAbstract:
Dans le cadre de cette thèse, nous nous intéressons à la coordination et l'optimisation du trafic aux intersections des réseaux routiers, avec la particularité de considérer des véhicules autonomes intelligents. Cette thèse est organisée en deux grandes parties. La première se concentre sur le problème du partage d'un espace de voie par deux files de véhicules évoluant en sens opposés. L'état de l'art montre le peu de travaux abordant cette question. Nous explorons deux approches par coordination réactive, en relation avec un critère de minimisation des retards. Les performances de ces approches ont été mesurées statistiquement en simulation. La deuxième partie de la thèse s'attaque au problème générique de la gestion du trafic au sein d'un réseau routier. Nous développons une approche originale à deux égards: d'une part elle explore un principe de passage en alternance des flux permettant de ne pas arrêter les véhicules aux intersections, et d'autre part, elle propose des algorithmes d'optimisationdistribuée de ce passage alterné au niveau de chaque intersection et au niveau du réseau global. La thèse présente successivement les choix de modélisation, les algorithmes et l'étude en simulation de leurs performances comparées à desapproches existantesIn this thesis, we focus on traffic coordination and optimization in road intersections, while accounting for intelligent autonomous vehicles. This thesis is organized in two parts. The first part focuses on the problem of sharing a one-lane road between two opposite flows of vehicles. The state of the art shows few studies addressing this issue. We propose two reactive coordination approaches that minimize vehicle delays and measure their performances statistically through simulations. The second part of the thesis addresses the problem of generic traffic management in a traffic network. We develop a stop-free approach that explores a principle alternating vehicles between flows at intersections, and it provides distributed algorithms optimizing this alternation at each intersection and in the overall network. We present the modeling choices, the algorithms and the simulation study of our approach and we compare its performances with existing approaches
28
Fink, Wolfgang, Alexander J. W. Brooks, Mark A. Tarbell, and James M. Dohm. "Tier-scalable reconnaissance: the future in autonomous C4ISR systems has arrived: progress towards an outdoor testbed." SPIE-INT SOC OPTICAL ENGINEERING, 2017. http://hdl.handle.net/10150/626010.
Full textAbstract:
Autonomous reconnaissance missions are called for in extreme environments, as well as in potentially hazardous (e.g., the theatre, disaster-stricken areas, etc.) or inaccessible operational areas (e.g., planetary surfaces, space). Such future missions will require increasing degrees of operational autonomy, especially when following up on transient events. Operational autonomy encompasses: (1) Automatic characterization of operational areas from different vantages (i.e., spaceborne, airborne, surface, subsurface); (2) automatic sensor deployment and data gathering; (3) automatic feature extraction including anomaly detection and region-of-interest identification; (4) automatic target prediction and prioritization; (5) and subsequent automatic (re-) deployment and navigation of robotic agents. This paper reports on progress towards several aspects of autonomous (CISR)-I-4 systems, including: Caltech-patented and NASA award-winning multi-tiered mission paradigm, robotic platform development (air, ground, water-based), robotic behavior motifs as the building blocks for autonomous telecommanding, and autonomous decision making based on a Caltech-patented framework comprising sensor-data-fusion (feature-vectors), anomaly detection (clustering and principal component analysis), and target prioritization (hypothetical probing).
29
Oyenan, Walamitien Hervé. "An algebraic framework for compositional design of autonomous and adaptive multiagent systems." Diss., Kansas State University, 2010. http://hdl.handle.net/2097/3869.
Full textAbstract:
Doctor of PhilosophyDepartment of Computing and Information Sciences
Scott A. DeLoach
Organization-based Multiagent Systems (OMAS) have been viewed as an effective paradigm for addressing the design challenges posed by today’s complex systems. In those systems, the organizational perspective is the main abstraction, which provides a clear separation between agents and systems, allowing a reduction in the complexity of the overall system. To ease the development of OMAS, several methodologies have been proposed. Unfortunately, those methodologies typically require the designer to handle system complexity alone, which tends to lead to ad-hoc designs that are not scalable and are difficult to maintain. Moreover, designing organizations for large multiagent systems is a complex and time-consuming task; design models quickly become unwieldy and thus hard to develop. To cope with theses issues, a framework for organization-based multiagent system designs based on separation of concerns and composition principles is proposed. The framework uses category theory tools to construct a formal composition framework using core models from the Organization-based Multiagent Software Engineering (O-MASE) framework. I propose a formalization of these models that are then used to establish a reusable design approach for OMAS. This approach allows designers to design large multiagent organizations by reusing smaller composable organizations that are developed separately, thus providing them with a scalable approach for designing large and complex OMAS. In this dissertation, the process of formalizing and composing multiagent organizations is discussed. In addition, I propose a service-oriented approach for building autonomous, adaptive multiagent systems. Finally, as a proof of concept, I develop two real world examples from the domain of cooperative robotics and wireless sensor networks.
30
Nayyar, Raghu. "Visualising Autonomous Warehouse Data Streams Through User-Centered Design." Thesis, KTH, Medieteknik och interaktionsdesign, MID, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-233195.
Full textAbstract:
This thesis aims to develop and evaluate a dashboard design that visualizes a stream of data from the different entities involved in autonomous warehouses, a subset of cyber-physical systems. I created this dashboard through User-Centered Design (UCD) methodologies based on two feedback iterations with the stakeholders employing semi-structured expert opinion interviews. This thesis also discusses the different stages involved in building this dashboard design, the design decisions, the technical aspects of the libraries used, and the feedback session towards the end of the project. It also presents the implemented dashboard as a proof of development efforts and explains its different functionalities. The project concludes with evaluating the dashboard through a semi-structured interview with the respective stakeholders and suggests features for further development.Denna studie ämnar att utveckla och utvärdera en design för ett dashboard som visualiserar dataströmmar från olika enheter som kan hittas i autonoma lager. Detta dashboard har utvecklats genom att använda metoder inom användarcentrerad design, som baserades på två iterationer med intressenter som är experter inom området, där semistrukturerade intervjuer gjordes. Denna studie diskuterar också de olika steg som är involverade i att bygga designen av detta dashboard, de olika beslut som togs i designprocessen, de tekniska aspekterna av de bibliotek som används och resultatet från de sessioner som hölls för att få feedback i slutet av projektet. Studien presenterar också det dashboard som utvecklades samt förklarar dess funktionalitet. Slutsatser dras från de semistrukturerade intervjuerna med respektive intressent och föreslår framtida funktioner som skulle vara möjliga att implementera.
31
Karpowitz, Daniel J. "A Dynamic Workflow Framework for Mass Customization Using Web Service and Autonomous Agent Technologies." Diss., CLICK HERE for online access, 2006. http://contentdm.lib.byu.edu/ETD/image/etd1647.pdf.
Full text
32
Davis, Cledo L. "The systems integration of autonomous behavior analysis to create a "Maritime Smart Environment" for the enhancement of maritime domain awareness." Thesis, Monterey, California : Naval Postgraduate School, 2010. http://edocs.nps.edu/npspubs/scholarly/theses/2010/Jun/10Jun%5FDavis.pdf.
Full textAbstract:
Thesis (M.S. in Systems Engineering)--Naval Postgraduate School, June 2010.Thesis Advisor(s): Goshorn, Rachel ; Goshorn, Deborah. "June 2010." Description based on title screen as viewed on June 24, 2010. Author(s) subject terms: Anomaly Detection, Artificial Intelligence, Automation, Behavior Analysis, Distributed Artificial Intelligence, Intelligence-Surveillance-Reconnaissance, Maritime Domain Awareness, Maritime Force Protection, Multi-agent Systems, Network-centric Operations, Network-centric Systems Engineering, Network-centric Warfare, Smart Sensor Networks, Systems Engineering, Systems Integration, System of Systems. Includes bibliographical references (p. 209-212). Also available in print.
33
Hamoui, Mohamad Fady. "Un système multi-agents à base de composants pour l’adaptation autonomique au contexte – Application à la domotique." Thesis, Montpellier 2, 2010. http://www.theses.fr/2010MON20088/document.
Full textAbstract:
Les environnements domotiques sont des environnements ubiquitaires dans lesquels des équipements domestiques, disséminés dans une habitation, fournissent des services utilisables à distance au travers d'un réseau. Des systèmes domotiques sont proposés pour permettre aux utilisateurs de contrôler les équipements en fonction de leurs besoins.Idéalement, ces systèmes orchestrent l'exécution des services fournis par les équipements pour réaliser des services complexes. Mieux encore, ces systèmes doivent s'adapter à la variété des environnements en termes d'équipements et des besoins des utilisateurs. Ils doivent également pouvoir s'adapter dynamiquement, si possible de manière autonome, au changement de leur contexte d'exécution (apparition ou disparition d'un équipement, évolution des besoins).Dans cette thèse, nous apportons une réponse à cette problématique avec SAASHA, un système domotique multi-agents à base de composants. La combinaison de ses deux paradigmes permet de gérer l'adaptation à trois niveaux : présentation (interfaces utilisateur),organisation (architecture du système) et comportement (architecture interne des agents).Les agents perçoivent le contexte et ses changements. Les utilisateurs se voient proposer une vue dynamique du contexte leur permettant de définir des scénarios personnalisés sous forme de règles. Les agents se répartissent les rôles pour réaliser les scénarios. Ils modifient dynamiquement leur architecture interne grâce à la génération, au déploiement et à l'assemblage de composants pour se doter de nouveaux comportements de contrôle des équipements et des scénarios. Les agents collaborent ainsi pour exécuter les scénarios. En cas de changement, ces trois niveaux d'adaptation sont mis en oeuvre de manière dynamique et autonome pour maintenir la continuité de service. Un prototype de SAASHA, basé sur les standards industriels UPnP et OSGi, a été développé pour évaluer la faisabilité de notre propositionHome automation environments are ubiquitous environments where domestic devices, scattered throughout a home, provide services that can be used remotely over a network. Home automation systems are proposed to enable the users of controlling the devices according to their needs. Ideally, these systems orchestrate the execution of the services provided by the devices to achieve complex services. Even more, these systems must adapt to the variety of environments in terms of devices and users needs. They must also be able to adapt dynamically, if possible in an autonomous manner, to the changes of their execution context (appearance or disappearance of a device, changing needs).In this thesis, we provide an answer to this problematic with SAASHA, a multi-agent home automation system based on components. The combination of these two paradigms enables managing the adaptation on three levels: presentation (user interface), organization (system architecture) and behavior (internal architecture of agents). The agents perceive their context and its changes. The Users are offered a dynamic view of the context allowing them to define custom scenarios as rules. The agents divide the roles among them to realize the scenarios. They modify dynamically their internal architecture throughout the generation, deployment and assembly of components to adopt new device control behaviors and scenarios. The agents collaborate to execute the scenarios. In case of a change, these three levels of adaptation are updated dynamically and autonomously to maintain the service continuity. A SAASHA prototype, based on UPnP and OSGi industry standards, has been developed to assess the feasibility of our proposal
34
Anzalone, Evan John. "Agent and model-based simulation framework for deep space navigation analysis and design." Diss., Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/52163.
Full textAbstract:
As the number of spacecraft in simultaneous operation continues to grow, there is an increased dependency on ground-based navigation support. The current baseline system for deep space navigation utilizes Earth-based radiometric tracking, which requires long duration, often global, observations to perform orbit determination and generate a state update. The age, complexity, and high utilization of the assets that make up the Deep Space Network (DSN) pose a risk to spacecraft navigation performance. With increasingly complex mission operations, such as automated asteroid rendezvous or pinpoint planetary landing, the need for high accuracy and autonomous navigation capability is further reinforced.
The Network-Based Navigation (NNAV) method developed in this research takes advantage of the growing inter-spacecraft communication network infrastructure to allow for autonomous state measurement. By embedding navigation headers into the data packets transmitted between nodes in the communication network, it is possible to provide an additional source of navigation capability. Simulation results indicate that as NNAV is implemented across the deep space network, the state estimation capability continues to improve, providing an embedded navigation network.
To analyze the capabilities of NNAV, an analysis and simulation framework is designed that integrates navigation and communication analysis. Model-Based Systems Engineering (MBSE) and Agent-Based Modeling (ABM) techniques are utilized to foster a modular, expandable, and robust framework. This research has developed the Space Navigation Analysis and Performance Evaluation (SNAPE) framework. This framework allows for design, analysis, and optimization of deep space navigation and communication architectures. SNAPE captures high-level performance requirements and bridges them to specific functional requirements of the analytical implementation. The SNAPE framework is implemented in a representative prototype environment using the Python language and verified using industry standard packages.
The capability of SNAPE is validated through a series of example test cases. These analyses focus on the performance of specific state measurements to state estimation performance, and demonstrate the core analytic functionality of the framework. Specific cases analyze the effects of initial error and measurement uncertainty on state estimation performance. The timing and frequency of state measurements are also investigated to show the need for frequent state measurements to minimize navigation errors. The dependence of navigation accuracy on timing stability and accuracy is also demonstrated. These test cases capture the functionality of the tool as well as validate its performance.
The SNAPE framework is utilized to capture and analyze NNAV, both conceptually and analytically. Multiple evaluation cases are presented that focus on the Mars Science Laboratory's (MSL) Martian transfer mission phase. These evaluation cases validate NNAV and provide concrete evidence of its operational capability for this particular application. Improvement to onboard state estimation performance and reduced reliance on Earth-based assets is demonstrated through simulation of the MSL spacecraft utilizing NNAV processes and embedded packets within a limited network containing DSN and MRO. From the demonstrated state estimation performance, NNAV is shown to be a capable and viable method of deep space navigation. Through its implementation as a state augmentation method, the concept integrates with traditional measurements and reduces the dependence on Earth-based updates. Future development of this concept focuses on a growing network of assets and spacecraft, which allows for improved operational flexibility and accuracy in spacecraft state estimation capability and a growing solar system-wide navigation network.
35
Quesnel, Flavien. "Vers une gestion coopérative des infrastructures virtualisées à large échelle : le cas de l'ordonnancement." Phd thesis, Ecole des Mines de Nantes, 2013. http://tel.archives-ouvertes.fr/tel-00821103.
Full textAbstract:
Les besoins croissants en puissance de calcul sont généralement satisfaits en fédérant de plus en plus d'ordinateurs (ou noeuds) pour former des infrastructures distribuées. La tendance actuelle est d'utiliser la virtualisation système dans ces infrastructures, afin de découpler les logiciels des noeuds sous-jacents en les encapsulant dans des machines virtuelles. Pour gérer efficacement ces infrastructures virtualisées, de nouveaux gestionnaires logiciels ont été mis en place. Ces gestionnaires sont pour la plupart hautement centralisés (les tâches de gestion sont effectuées par un nombre restreint de nœuds dédiés). Cela limite leur capacité à passer à l'échelle, autrement dit à gérer de manière réactive des infrastructures de grande taille, qui sont de plus en plus courantes. Au cours de cette thèse, nous nous sommes intéressés aux façons d'améliorer cet aspect ; l'une d'entre elles consiste à décentraliser le traitement des tâches de gestion, lorsque cela s'avère judicieux. Notre réflexion s'est concentrée plus particulièrement sur l'ordonnancement dynamique des machines virtuelles, pour donner naissance à la proposition DVMS (Distributed Virtual Machine Scheduler). Nous avons mis en œuvre un prototype, que nous avons validé au travers de simulations (notamment via l'outil SimGrid), et d'expériences sur le banc de test Grid'5000. Nous avons pu constater que DVMS se montrait particulièrement réactif pour gérer des infrastructures virtualisées constituées de dizaines de milliers de machines virtuelles réparties sur des milliers de nœuds. Nous nous sommes ensuite penchés sur les perspectives d'extension et d'amélioration de DVMS. L'objectif est de disposer à terme d'un gestionnaire décentralisé complet, objectif qui devrait être atteint au travers de l'initiative Discovery qui fait suite à ces travaux.
36
de, Freitas Edison Pignaton, Tales Heimfarth, Armando Morado Ferreira, Flávio Rech Wagner, Carlos Eduardo Pereira, and Tony Larsson. "An agent framework to support sensor networks’ setup and adaptation." Högskolan i Halmstad, Inbyggda system (CERES), 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-14691.
Full textAbstract:
Sensor networks are being used in several emerging applications not even imagined some years ago due to advances in sensing, computing, and communication techniques. However, these advances also pose various challenges that must be faced. One important challenge is related to the autonomous capability needed to setup and adapt the networks, which decentralizes the control of the network, saving communication and energy resources. Middleware technology helps in addressing this kind of problem, but there is still a need for additional solutions, particularly considering dynamic changes in users' requirements and operation conditions. This paper presents an agent-based framework acting as an integral part of a middleware to support autonomous setup and adaptation of sensor networks. It adds interoperability among heterogeneous nodes in the network, by means of autonomous behavior and reasoning. These features also address the needs for system setup and adaptations in the network, reducing the communication overhead and decentralizing the decision making mechanism. Additionally, preliminary results are also presented.
37
Leitner, Jürgen. "From vision to actions: Towards adaptive and autonomous humanoid robots." Thesis, Università della Svizzera Italiana, 2014. https://eprints.qut.edu.au/90178/2/2014INFO020.pdf.
Full textAbstract:
Although robotics research has seen advances over the last decades robots are still not in widespread use outside industrial applications. Yet a range of proposed scenarios have robots working together, helping and coexisting with humans in daily life. In all these a clear need to deal with a more unstructured, changing environment arises. I herein present a system that aims to overcome the limitations of highly complex robotic systems, in terms of autonomy and adaptation. The main focus of research is to investigate the use of visual feedback for improving reaching and grasping capabilities of complex robots. To facilitate this a combined integration of computer vision and machine learning techniques is employed. From a robot vision point of view the combination of domain knowledge from both imaging processing and machine learning techniques, can expand the capabilities of robots. I present a novel framework called Cartesian Genetic Programming for Image Processing (CGP-IP). CGP-IP can be trained to detect objects in the incoming camera streams and successfully demonstrated on many different problem domains. The approach requires only a few training images (it was tested with 5 to 10 images per experiment) is fast, scalable and robust yet requires very small training sets. Additionally, it can generate human readable programs that can be further customized and tuned. While CGP-IP is a supervised-learning technique, I show an integration on the iCub, that allows for the autonomous learning of object detection and identification. Finally this dissertation includes two proof-of-concepts that integrate the motion and action sides. First, reactive reaching and grasping is shown. It allows the robot to avoid obstacles detected in the visual stream, while reaching for the intended target object. Furthermore the integration enables us to use the robot in non-static environments, i.e. the reaching is adapted on-the- fly from the visual feedback received, e.g. when an obstacle is moved into the trajectory. The second integration highlights the capabilities of these frameworks, by improving the visual detection by performing object manipulation actions.
38
Vemulapalli, Manish Goldie. "Resource allocation problems in communication and control systems." Diss., University of Iowa, 2012. https://ir.uiowa.edu/etd/3547.
Full textAbstract:
Resource allocation in control and communication systems constitutes the distribution of (finite) system resources in a way that achieves maximum system functionality and or cost effectiveness. Specific resource allocation problems in subband coding, Discrete Multi-tone modulation based systems and autonomous multi-agent control are addressed in this thesis.
In subband coding, the number of bits used (out of a target bit budget) to code a sub- band signal are allocated in a way that minimizes the coding distortion. In Discrete Multi-tone modulation based systems, high bit rate streams are split into several parallel lower rate streams. These individual data streams are transmitted over different subchannels. Given a target bit rate, the goal of resource allocation is to distribute the bits among the different subchannels such that the total transmitted power is minimized. The last problem is achieving stable control of a fleet of autonomous agents by utilizing the available communication resources (such as transmitted Power and bandwidth) as effectively as possible.
We present an efficient bit loading algorithm that applies to both subband coding and single-user multicarrier communication system. The goal is to effect an optimal distribution of B bits among N subchannels (subbands) to achieve a minimum transmitted power (distortion error variance) for multicarrier (subband coding) systems. All the algorithms in literature, except a few (which provides a suboptimal solution), have run times that increase with B. By contrast, we provide an algorithm that solves the aforementioned problems exactly and with a complexity (given by O(N log(N)),) which is dependent only on N.
Bit loading in multi-user multicarrier systems not only involves the distribution of bit rates across the subchannels but also the assignment of these subchannels to different users. The motivation for studying suboptimal bit allocation is underscored by implicit and explicit claims made in some of the papers which present suboptimal bit loading algorithms, without a formal proof, that the underlying problem is NP-hard. Consequently, for no other reason than the sake of completeness, we present a proof for NP-hardness of the multiuser multicarrier bit loading problem, thereby formally justifying the search for suboptimal solutions.
There has been a growing interest in the area of cooperative control of networks of mobile autonomous agents. Applications for such a set up include organization of large sensor networks, air traffic control, achieving and maintaining formations of unmanned vehicles operating under- water, air traffic control etc. As in Abel et al, our goal is to devise control laws that, require minimal information exchange between the agents and minimal knowledge on the part of each agent of the overall formation objective, are fault tolerant, scalable, and easily reconfigurable in the face of the loss or arrival of an agent, and the loss of a communication link.
A major drawback of the control law proposed in Abel et al is that it assumes all agents can exchange information at will. This is fine if agents acquire each others state information through straightforward sensing. If however, state information is exchanged through broadcast commu- nication, this assumption is highly unrealistic. By modifying the control law presented in Abel et al, we devise a scheme that allows for a sharing of the resource, which is the communication channel, but also achieves the desired formation stably. Accordingly we modify the control law presented in [23] to be compatible with networks constrained by MAC protocols.
39
Calfee, Sharif H. "Autonomous agent-based simulation of an AEGIS Cruiser combat information center performing battle air-defense commander operations." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2003. http://library.nps.navy.mil/uhtbin/hyperion-image/03Mar%5FCalfee.pdf.
Full text
40
Mouad, Mehdi. "Architecture de COntrôle/COmmande dédiée aux systèmes Distribués Autonomes (ACO²DA) : application à une plate-forme multi-véhicules." Thesis, Clermont-Ferrand 2, 2014. http://www.theses.fr/2014CLF22437/document.
Full textAbstract:
La complexité associée à la coordination d’un groupe de robots mobiles est traitée dans cette thèse en investiguant plus avant les potentialités des architectures de commande multi-contrôleurs dont le but est de briser la complexité des tâches à exécuter. En effet, les robots mobiles peuvent évoluer dans des environnements très complexes et nécessitent de surcroît une coopération précise et sécurisée pouvant rapidement devenir inextricable. Ainsi, pour maîtriser cette complexité, le contrôleur dédié à la réalisation d’une tâche est décomposé en un ensemble de comportements/contrôleurs élémentaires (évitement d’obstacles et de collision entre les robots, attraction vers une cible, planification, etc.) qui lient les informations capteurs (provenant des capteurs locaux du robot, etc.) aux actionneurs des différentes entités robotiques. La tâche considérée dans cette thèse correspond à la navigation d’un groupe de robots mobiles dans des environnements peu ou pas connus en présence d’obstacles (statiques et dynamiques). La spécificité de l’approche théorique consiste à allier les avantages des architectures multi-contrôleurs à ceux des systèmes multi-agents et spécialement les modèles organisationnels afin d’apporter un haut niveau de coordination entre les agents/robots mobiles. Le groupe de robots mobiles est alors coordonné suivant les différentes normes et spécifications du modèle organisationnel. Ainsi, l’activation d’un comportement élémentaire en faveur d’un autre se fait en respectant les contraintes structurelles des robots en vue d’assurer le maximum de précision et de sécurité des mouvements coordonnés entre les différentes entités mobiles. La coopération se fait à travers un agent superviseur (centralisé) de façon à atteindre plus rapidement la destination désirée, les événements inattendus sont gérés quant à eux individuellement par les agents/robots mobiles de façon distribuée. L’élaboration du simulateur ROBOTOPIA nous a permis d’illustrer chacune des contributions de la thèse par un nombre important de simulationsThe difficulty of coordinating a group of mobile robots is adressed in this thesis by investigating control architectures which aim to break task complexity. In fact, multi-robot navigation may become rapidly inextricable, specifically if it is made in hazardous and dynamical environment requiring precise and secure cooperation. The considered task is the navigation of a group of mobile robots in unknown environments in presence of (static and dynamic) obstacles. To overcome its complexity, it is proposed to divide the overall task into a set of basic behaviors/controllers (obstacle avoidance, attraction to a dynamical target, planning, etc.). Applied control is chosen among these controllers according to sensors information (camera, local sensors, etc.). The specificity of the theoretical approach is to combine the benefits of multi-controller control architectures to those of multi-agent organizational models to provide a high level of coordination between mobile agents-robots systems. The group of mobile robots is then coordinated according to different norms and specifications of the organizational model. Thus, activating a basic behavior in favor of another is done in accordance with the structural constraints of the robots in order to ensure maximum safety and precision of the coordinated movements between robots. Cooperation takes place through a supervisor agent (centralized) to reach the desired destination faster ; unexpected events are individually managed by the mobile agents/robots in a distributed way. To guarantee performance criteria of the control architecture, hybrid systems tolerating the control of continuous systems in presence of discrete events are explored. In fact, this control allows coordinating (by discrete part) the different behaviors (continuous part) of the architecture. The development of ROBOTOPIA simulator allowed us to illustrate each contribution by many results of simulations
41
Dürr, Hans-Bernd. "Distributed Positioning of Autonomous Mobile Sensors with Application to the Coverage Problem : A Game Theoretic Approach to Multi-Agent Systems." Thesis, KTH, Reglerteknik, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-105128.
Full textAbstract:
In this thesis, general problems are considered where a group of agents should autonomously position themselves in such a way that a global objective function is maximized, whereas each agent uses only the measurement of its own utility function. Specially constructed extremum seeking schemes for single and multi-agent systems are presented, where the agents have only access to the current value of their individual utility functions and do not know the analytical model of the global or local objectives. By using an approximative system that is calculated using a methodology based on Lie brackets, practical stability of an equilibrium point is proved for the single agent as well as for the multi-agent case. The motion dynamics of the agents are modeled as single integrators, double integrators and unicycles. A potential game approach is used in order to deduce conditions under which the whole group of agents converges to a region arbitrary close to the maximum of a global objective function, that coincides with the Nash equilibrium of the game. As an application of the proposed algorithms, the sensor coverage problem is introduced. In this problem, a group of autonomous sensors is meant to position themselves such that a certain region is covered optimally, in the sense that the amount of detected events appearing in this region, is maximized. The problem is interpreted as a potential game where individual utility functions for each sensor are constructed in a way suitable for the direct application of the proposed optimization methodology.
42
Carlési, Nicolas. "Coopération entre véhicules sous-marins autonomes : une approche organisationnelle réactive multi-agent." Thesis, Montpellier 2, 2013. http://www.theses.fr/2013MON20092.
Full textAbstract:
Les applications sous-marines actuelles exigent la réalisation de travaux de différentes natures dans des zones de plus en plus vastes et toujours plus profondes. La conception et l'utilisation de flottilles d'AUV dans ce contexte est un véritable challenge. Les bénéfices attendus sontmultiples. Premièrement, cela doit permettre de minimiser les coûts grâce à une répartition de ceux-ci sur l'ensemble de la flottille : la perte d'un AUV ou son mauvais fonctionnement ne remettront pas en cause l'intégralité de la mission. Deuxièmement, l'utilisation d'une flottilledoit de fait permettre de réduire le temps d'exécution d'une mission grâce à la parallélisation de certaines tâches. Enfin, la réalisation d'une mission par une flottille permet de conserver le caractère spécialisé des AUV et donc d'envisager plus facilement leur réutilisation dansd'autres contextes. Cependant, les approches de coopération multi-AUV existantes sont limitées par deux principaux verrous : (1) le nombre de communications induit et (2) la gestion de l'hétérogénéité potentielle d'une flottille.L'approche que nous proposons vise à répondre à ces problématiques.L'idée principale est de combiner une approche de coopération réactive avec une approche organisationnelle. L'approche de coopération réactive permet l'échange des signaux de communication très simples. Cependant, elle ne permet de résoudre que des problèmes de coopération de nature assez restreinte qui concernent essentiellement la coordination spatiale de véhicules homogènes. La première contribution de cette thèse est l'extension de l'approche satisfaction-altruisme. Un nouveau mécanisme décisionnel réactif, capable de considérer des actions coopératives de diverses natures, est proposé. La deuxième contribution consiste à spécifier les contextes d'interactions réactives à l'aide d'une approche organisationnelle. Le modèle organisationnel Agent/Groupe/Rôle est utilisé pour avoir une représentation explicite de l'organisation de la flottille. Les concepts de groupe, mais surtout de rôle, sont employés dans l'adressage des signaux de communication et permettent la mise en oeuvre d'interactions hétérogènes avec une grande modularité. L'ensemble est intégré dans une nouvelle architecture logicielle, appelée REMORAS, destinée à équiper des véhicules sous-marins autonomes. Une validation de la faisabilité de notre approche est proposée à l'aide d'une simulation de plusieurs scénarios mettant en jeu des AUV hétérogènesUnderwater marine applications are nowadays branching into various fields covering larger and deeper zones. Performing the required tasks with the aid of AUV flotillas is a real challenge. However, the advantages of using such a new technology are numerous. Firstly, this would highly reduce the cost of the mission thanks to the distribution of this former among the various AUV: the loss of one AUV or its bad functioning will not degrade the performance of the flotilla in general. Secondly, the use of a flotilla reduces the execution time of a mission given the parallelization of certain tasks. Finally, any mission can be accomplished by the flotilla by taking into consideration the specificity of each AUV. In fact, each of these vehicles holds different characteristics rendering the global architecture heterogeneous and therefore applicable in different contexts. However, the methods concerned with multi-AUV cooperation are hindered by two main limitations: (1) the number of communications induced and (2) the management of the heterogeneity in the flotilla.The proposed approach aims at responding to these challenges. The principal idea is to combine this reactive cooperational approach with an organizational one. The reactive cooperational approach allows the exchange of simple communication signals. However, it does not help in solving the problems of cooperation that are very constrained and that mainly concern the spatial coordination of homogeneous vehicles. The first contribution in this thesis is the extension of the satisfaction-altruism approach. A new reactive decisional mechanism capable of considering the cooperative actions of various natures is proposed. The second contribution consists in specifying the context of reactive interactions based on an organizational approach. The organizational model Agent/Group/Role is used in order to have an explicit representation of the flotilla. The concepts of "group" and especially "role" are used in the attribution of the communication signals allowing the accomplishment of heterogeneous interactions with a big modularity. A new concept is therefore born and is integrated in a new software architecture called REMORA intended to equip autonomous underwater vehicles. This proposed new method has been validated through various numerical simulations in different scenarios putting at stake heterogeneous AUV
43
Windridge, David, Michael Felsberg, and Affan Shaukat. "A Framework for Hierarchical Perception–Action Learning Utilizing Fuzzy Reasoning." Linköpings universitet, Datorseende, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-85688.
Full textAbstract:
Perception-action (P-A) learning is an approach to cognitive system building that seeks to reduce the complexity associated with conventional environment-representation/action-planning approaches. Instead, actions are directly mapped onto the perceptual transitions that they bring about, eliminating the need for intermediate representation and significantly reducing training requirements. We here set out a very general learning framework for cognitive systems in which online learning of the P-A mapping may be conducted within a symbolic processing context, so that complex contextual reasoning can influence the P-A mapping. In utilizing a variational calculus approach to define a suitable objective function, the P-A mapping can be treated as an online learning problem via gradient descent using partial derivatives. Our central theoretical result is to demonstrate top-down modulation of low-level perceptual confidences via the Jacobian of the higher levels of a subsumptive P-A hierarchy. Thus, the separation of the Jacobian as a multiplying factor between levels within the objective function naturally enables the integration of abstract symbolic manipulation in the form of fuzzy deductive logic into the P-A mapping learning. We experimentally demonstrate that the resulting framework achieves significantly better accuracy than using P-A learning without top-down modulation. We also demonstrate that it permits novel forms of context-dependent multilevel P-A mapping, applying the mechanism in the context of an intelligent driver assistance system.DIPLECS
GARNICS
CUAS
44
Chintalapati, Veera Venkata Tarun Kartik. "Multi-Vehicle Path Following and Adversarial Agent Detection in Constrained Environments." University of Cincinnati / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1613751238253121.
Full text
45
Landén, David. "Complex Task Allocation for Delegation : From Theory to Practice." Licentiate thesis, Linköpings universitet, KPLAB - Laboratoriet för kunskapsbearbetning, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-70536.
Full textAbstract:
The problem of determining who should do what given a set of tasks and a set of agents is called the task allocation problem. The problem occurs in many multi-agent system applications where a workload of tasks should be shared by a number of agents. In our case, the task allocation problem occurs as an integral part of a larger problem of determining if a task can be delegated from one agent to another. Delegation is the act of handing over the responsibility for something to someone. Previously, a theory for delegation including a delegation speech act has been specified. The speech act specifies the preconditions that must be fulfilled before the delegation can be carried out, and the postconditions that will be true afterward. To actually use the speech act in a multi-agent system, there must be a practical way of determining if the preconditions are true. This can be done by a process that includes solving a complex task allocation problem by the agents involved in the delegation. In this thesis a constraint-based task specification formalism, a complex task allocation algorithm for allocating tasks to unmanned aerial vehicles and a generic collaborative system shell for robotic systems are developed. The three components are used as the basis for a collaborative unmanned aircraft system that uses delegation for distributing and coordinating the agents' execution of complex tasks.
46
Seppecher, Pascal. "Modélisation multi-agents d'une économie monétaire de production : un système dynamique et complexe d'interactions réelles et monétaires entre des agents multiples, hétérogènes, autonomes et concurrents." Phd thesis, Université de Nice Sophia-Antipolis, 2011. http://tel.archives-ouvertes.fr/tel-00693151.
Full textAbstract:
Nous présentons un modèle numérique d'économie de marché décentralisée, fonctionnant hors de l'équilibre, composée de deux grands groupes d'agents (entreprises et ménages) auxquels sont respectivement associées deux fonctions économiques principales (production et consommation). Ces fonctions s'exercent dans le respect des règles des économies capitalistes (propriété privée des moyens de production, échanges monétaires, salariat). Les agents sont des individus en interaction directe et indirecte (et non des agents représentatifs ou des agrégats), chacun poursuivant son propre but, agissant en fonction de son état individuel et de l'environnement proche, sans se préoccuper du tout de l'équilibre général du système et sans contrôle supérieur (ni de la part d'un planificateur, ni d'un commissaire-priseur). Le modèle respecte les trois principes essentiels des économies monétaires: - le processus de production prend du temps et les entreprises ont besoin de crédit pour lancer ce processus; - la monnaie est endogène, elle est créée par le crédit bancaire à la production; - les entreprises sont guidées par le motif de profit et ce profit est monétaire. Implémenté en Java, le modèle se présente comme un laboratoire virtuel permettant de conduire de véritables expériences "in silico". Les interactions réelles et monétaires entre les agents (multiples, hétérogènes, autonomes et concurrents) forment un système dynamique et complexe dont les propriétés macroéconomiques ne sont pas postulées. Nous reconstruisons ainsi les conditions de l'émergence de comportements macroéconomiques inobservables dans les modèles basés sur les notions d'agent représentatif et d'équilibre général.
47
Bengtsson, Björn. "Dynamisk Kollisionsundvikande I Twin Stick shooter : Hastighetshinder och partikelseparation." Thesis, Högskolan i Skövde, Institutionen för informationsteknologi, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-16990.
Full textAbstract:
I examensarbetet jämförs undvikande av kollision och tidsefektivitet mellan det två metoderna hastighetshinder och partikelseparation i spelgenren Twin stick shooter. Arbetet försöker besvara frågan: Hur skiljer sig undvikandet av kollision och tidseffektiviteten mellan metoderna hastighetshinder och partikelseparation, i spelgenren twin stick shooter med flockbeteende? För att besvara frågan har en artefakt skapats. I artefakten jagar agenter en spelare medan agenterna undviker kollision med andra agenter, dock eftersträvar agenterna att kollidera med spelaren. I artefakten körs olika experiment baserat på parametrar som har ställts in. Varje experiment körs en bestämd tid och all data om kollisioner och exekveringstid för respektive metod sparas i en textfil. Resultatet av experimenten pekar på att partikelseparation lämpar sig bättre för twin stick shooters. Hastighetshinder kolliderar mindre men tidsberäkningen är för hög och skalar dåligt med antal agenter. Det passar inte twinstick shooter då det oftast är många agenter på skärmen. Metoderna för undvikandet av kollision har användning till radiostyrda billar och robotar, samt simulation av folkmassa.
48
Isfoula, Fayrouz. "Une approche du suivi de consensus pour les systèmes multi-agents." Thesis, Poitiers, 2019. http://www.theses.fr/2019POIT2303.
Full textAbstract:
Un système multi-agents est composé d’un ensemble d’agents interagissant entre eux et avec leur environnement, un agent étant vu comme un système dynamique autonome. La force des SMA repose sur la capacité des agents à coopérer entre eux pour atteindre un objectif qu’un agent seul ne pourrait atteindre. Chaque agent partage ses informations avec ses voisins, ce qui permet à l’ensemble des agents de s’accorder sur un objectif commun sans qu’il y ait pour autant une centralisation de l’information et de l’objectif. En ce sens, un système multi-agents peut être vu comme un réseau dans lequel l’information est distribuée. L’intérêt croissant pour le contrôle distribué et la coordination des réseaux constitués d’agents autonomes est motivé par l’absence de centralisation de l’information et la possibilité d’avoir une topologie du réseau variable. Les algorithmes de contrôle déployés sur ces réseaux sont de nature distribuée puisqu’ils s’appuient sur des informations locales, et sont robustes vis-à-vis des variations de topologie et de taille du réseau. Le problème le plus étudié dans le cadre de ces systèmes multi-agents est celui du consensus, qui peut être résumé ainsi : étant donné des conditions initiales pour chaque agent, quelles sont les conditions pour que les agents s’accordent asymptotiquement sur une valeur commune en n’échangeant que des informations entre agents voisins. Cette thèse traite du développement de commandes permettant d’atteindre ce consensus pour des topologies fixes et variables, en présence ou non d’un leader (suivi de consensus), et sur la qualité des informations transitant dans le réseau. En suivi de consensus, la notion de leader perceptif est développée et une commande est proposée pour une topologie fixe et variableAn agent is an autonomous dynamics system that can coordinate with the environment as well as with other agents. A group of these autonomous agents working in coordination is called a Multi-agent system (MAS). A MAS has several advantages over single agent operation. The main objective of MAS is to achieve a complex goal which is hard to achieve by a single agent. In MAS, each agent shares its information (states) to the neighbors only to complete the task hence no centralized monitoring systems is required. We can define a multi-agent system as a network in which information is distributed. The interest of researchers in the study of distributed control and distributed coordination of autonomous agent networks is motivated by the fact that it has the ability to cope with the problems associated with centralized communication network and also allow the switching network topologies.The algorithms for distributed networks only use local information, and are robust to variations of network topology and can accommodate network with large size.One of the most studied problems in the field of MAS is the consensus, which can be defined as: for any initial conditions for all agent, what are the conditions that should hold in order that the agents agree on a common value asymptotically while only information is exchanged between neighboring agents.This thesis deals with the development of control law to achieve the consensus for fixed and switching topologies, with or without a leader (consensus tracking). It also investigates the problem of the quality of information in the network. In consensus tracking, the notion of perceptive leader is developed and a control law is proposed for a fixed and switching topology
49
Frasheri, Mirgita. "Collaborative Adaptive Autonomous Agents." Licentiate thesis, Mälardalens högskola, Inbyggda system, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-40255.
Full text
50
Grey, Stuart. "Distributed agents for autonomous spacecraft." Thesis, University of Glasgow, 2013. http://theses.gla.ac.uk/3830/.
Full textAbstract:
Space missions have evolved considerably in the last fifty years in both complexity and ambition. In order to enable this continued improvement in the scientific and commercial return of space missions new control systems are needed that can manage complex combinations of state of the art hardware with a minimum of human interaction. Distributed multi-agent systems are one approach to controlling complex multisatellite space missions. A distributed system is not enough on its own however,the spacecraft must be able to carry out complex tasks such as planning,negotiation and close proximity formation flying autonomously. It is the coupling of distributed control with autonomy that is the focus of this thesis. Three contributions to the state of the art are described herein. They all involve the innovative use of multi-agent systems in space missions. The first is the development of a multi-agent architecture, HASA, specifically for space missions. The second is to use embedded agents to autonomously control an interferometric type space telescope. The third is based on software agents that coordinate multiple Earth observation missions coupled with a global optimisation technique for data extraction. The HASA architecture was developed in reaction to the over generality of most multi-agent architectures in the computer science and robotics literature and the ad-hoc, case-by-case approach, to multi-agent architectures when developed and deployed for space missions. The HASA architecture has a recursive nature which allows for the multi-agent system to be completely described throughout its development process as the design evolves and more sub-systems are implemented. It also inherits a focus on the robust generation of a product and safe operation from architectures in use in the manufacturing industry. A multi-agent system was designed using the HASA architecture for an interferometric space telescope type mission. This type of mission puts high requirements on formation flying and cooperation between agents. The formation flying agents were then implemented using a Java framework and tested on a multi-platform distributed simulation suite developed especially for this thesis. Three different control methods were incorporated into the agents and the multi-agent system was shown to be able to acquire and change formation and avoid collisions autonomously. A second multi-agent system was designed for the GMES mission in collaboration with GMV, the industrial partner in this project. This basic MAS design was transferred to the HASA architecture. A novel image selection algorithm was developed to work alongside the GMES multi-agent system. This algorithm uses global optimisation techniques to suggest image parameters to users based on the output of the multi-agent system.