Thesis (M.S. in Operations Research)--Naval Postgraduate School, June 2009. / Thesis Advisor(s): Horne, Gary E. "June 2009." Description based on title screen as viewed on July 13, 2009. Author(s) subject terms: border security, border protection, border patrol, unmanned aerial system (UAS), UAV, MANA, Nearly-Orthogonal Latin Hypercube, regression tree, linear regression. Includes bibliographical references (p. 89-93). Also available in print.

Veículos aéreos não-tripulados (VANTs) são relativamente recentes no meio acadêmico, onde muitas tecnologias e algoritmos vêm sendo pesquisados e desenvolvidos. A engenharia de software apliacada a este âmbito possui poucas abordagens em relação a sistemas autônomos e inteligentes, enquanto que sistemas multi-agentes e a programação orientada a agentes vêm sendo cada vez mais utilizadas. Este trabalho foca na aplicação do paradigma da programação orientada a agentes para o controle de VANTs, de modo a conceber um framework e utilizar arquitetura, teoria e ferramentas orientados a agentes como forma de prover uma abstração mais sofisticada para a programação de comportamentos inteligentes em VANTs. Na pesquisa, propõem-se o modelo UAVAS – Unmanned Aerial Vehicles AgentSpeak que é um framework de programação de comportamentos para VANTs que possui um modelo de abstração de veículos aéreos tripulados para veículos aéreos não-tripulados. Ao final, a pesquisa foi avaliada e validada por meio de resultados obtidos em simulações com a infraestrutura implementada. Dois estudos de caso foram realizados, um com ênfase nas comunicações inter-VANTs e cooperação de time, e outro com ênfase nas verificações dos mapeamentos de sinais com o envio de dados da infraestrutura. Para cada um dos casos, simuladores específicos foram criados no intuito de observar as características pertinentes de cada estudo de caso. / Unmanned aerial vehicles (UAVs) are relatively new in civilian context, where many technologies and algorithms have been the focus at much research and development. Software engineering applied to this field has few approaches in relation to autonomous systems and intelligent behavior development, while multi-agent system and agent-oriented programming are being increasingly used. This work focuses on applying the paradigm of agent-oriented programming for the control of UAVs, in order to design a framework and use architecture, theory and agent oriented tools as a way to provide a more sophisticated abstraction for programming intelligent behaviors in UAVs . The main contribution of this work is an architecture that allows the use of the Jason platform to program multiagent system which can control teams of autonomous unmanned aerial vehicles. In this research, we propose the UAVAS - Unmanned Aerial Vehicles AgentSpeak model, which is a framework to program intelligent behaviors to UAVs and owns an abstraction model of manned aircraft to unmanned aerial vehicles. At the end, the survey was evaluated and validated by means of results from simulations in the implemented infrastructure. Two case studies were performed, with emphasis on inter-UAV communication and cooperation of team, and the another one focusing on mapping verifications of data signals sent to the infrastructure. For each case, specific simulators have been created in order to observe the relevant characteristics of each case study.

In this work, unmanned aerial vehicle-based non-destructive testing methods for concrete structures are evaluated and developed. There exists a need for improved infrastructure inspection techniques with increased expediency. Unmanned aerial vehicles (UAVs) are highly mobile and have shown promise towards achieving this directive, but more work is required to adapt traditional NDT methods to be UAV-compatible. To this end, concrete sounding techniques were evaluated with a quantitative acoustic frequency analysis procedure on a series of concrete slabs. One such method was adapted for use with a UAV and was used to detect subsurface voids in one of the concrete samples and offer a means of depth estimation. This work was complemented with experiments concerning UAV-based visual and infrared imaging techniques already in practice for UAV-based concrete inspection. Together, findings indicate the strengths and weaknesses of the NDTs tested and suggest further improvements for UAV-based NDTs and inspection strategies moving forward. Development of a novel sensor platform for UAV-based measurement, as well as results of an actual bridge inspection using infrared and optical methods demonstrate the present capabilities of the UAV-based instrumentation. / Graduate / 2019-07-03

abstract: There has been a vast increase in applications of Unmanned Aerial Vehicles (UAVs) in civilian domains. To operate in the civilian airspace, a UAV must be able to sense and avoid both static and moving obstacles for flight safety. While indoor and low-altitude environments are mainly occupied by static obstacles, risks in space of higher altitude primarily come from moving obstacles such as other aircraft or flying vehicles in the airspace. Therefore, the ability to avoid moving obstacles becomes a necessity for Unmanned Aerial Vehicles. Towards enabling a UAV to autonomously sense and avoid moving obstacles, this thesis makes the following contributions. Initially, an image-based reactive motion planner is developed for a quadrotor to avoid a fast approaching obstacle. Furthermore, A Dubin’s curve based geometry method is developed as a global path planner for a fixed-wing UAV to avoid collisions with aircraft. The image-based method is unable to produce an optimal path and the geometry method uses a simplified UAV model. To compensate these two disadvantages, a series of algorithms built upon the Closed-Loop Rapid Exploratory Random Tree are developed as global path planners to generate collision avoidance paths in real time. The algorithms are validated in Software-In-the-Loop (SITL) and Hardware-In-the-Loop (HIL) simulations using a fixed-wing UAV model and in real flight experiments using quadrotors. It is observed that the algorithm enables a UAV to avoid moving obstacles approaching to it with different directions and speeds. / Dissertation/Thesis / Doctoral Dissertation Computer Science 2015

Veículos aéreos não-tripulados (VANTs) são relativamente recentes no meio acadêmico, onde muitas tecnologias e algoritmos vêm sendo pesquisados e desenvolvidos. A engenharia de software apliacada a este âmbito possui poucas abordagens em relação a sistemas autônomos e inteligentes, enquanto que sistemas multi-agentes e a programação orientada a agentes vêm sendo cada vez mais utilizadas. Este trabalho foca na aplicação do paradigma da programação orientada a agentes para o controle de VANTs, de modo a conceber um framework e utilizar arquitetura, teoria e ferramentas orientados a agentes como forma de prover uma abstração mais sofisticada para a programação de comportamentos inteligentes em VANTs. Na pesquisa, propõem-se o modelo UAVAS – Unmanned Aerial Vehicles AgentSpeak que é um framework de programação de comportamentos para VANTs que possui um modelo de abstração de veículos aéreos tripulados para veículos aéreos não-tripulados. Ao final, a pesquisa foi avaliada e validada por meio de resultados obtidos em simulações com a infraestrutura implementada. Dois estudos de caso foram realizados, um com ênfase nas comunicações inter-VANTs e cooperação de time, e outro com ênfase nas verificações dos mapeamentos de sinais com o envio de dados da infraestrutura. Para cada um dos casos, simuladores específicos foram criados no intuito de observar as características pertinentes de cada estudo de caso. / Unmanned aerial vehicles (UAVs) are relatively new in civilian context, where many technologies and algorithms have been the focus at much research and development. Software engineering applied to this field has few approaches in relation to autonomous systems and intelligent behavior development, while multi-agent system and agent-oriented programming are being increasingly used. This work focuses on applying the paradigm of agent-oriented programming for the control of UAVs, in order to design a framework and use architecture, theory and agent oriented tools as a way to provide a more sophisticated abstraction for programming intelligent behaviors in UAVs . The main contribution of this work is an architecture that allows the use of the Jason platform to program multiagent system which can control teams of autonomous unmanned aerial vehicles. In this research, we propose the UAVAS - Unmanned Aerial Vehicles AgentSpeak model, which is a framework to program intelligent behaviors to UAVs and owns an abstraction model of manned aircraft to unmanned aerial vehicles. At the end, the survey was evaluated and validated by means of results from simulations in the implemented infrastructure. Two case studies were performed, with emphasis on inter-UAV communication and cooperation of team, and the another one focusing on mapping verifications of data signals sent to the infrastructure. For each case, specific simulators have been created in order to observe the relevant characteristics of each case study.

Veículos aéreos não-tripulados (VANTs) são relativamente recentes no meio acadêmico, onde muitas tecnologias e algoritmos vêm sendo pesquisados e desenvolvidos. A engenharia de software apliacada a este âmbito possui poucas abordagens em relação a sistemas autônomos e inteligentes, enquanto que sistemas multi-agentes e a programação orientada a agentes vêm sendo cada vez mais utilizadas. Este trabalho foca na aplicação do paradigma da programação orientada a agentes para o controle de VANTs, de modo a conceber um framework e utilizar arquitetura, teoria e ferramentas orientados a agentes como forma de prover uma abstração mais sofisticada para a programação de comportamentos inteligentes em VANTs. Na pesquisa, propõem-se o modelo UAVAS – Unmanned Aerial Vehicles AgentSpeak que é um framework de programação de comportamentos para VANTs que possui um modelo de abstração de veículos aéreos tripulados para veículos aéreos não-tripulados. Ao final, a pesquisa foi avaliada e validada por meio de resultados obtidos em simulações com a infraestrutura implementada. Dois estudos de caso foram realizados, um com ênfase nas comunicações inter-VANTs e cooperação de time, e outro com ênfase nas verificações dos mapeamentos de sinais com o envio de dados da infraestrutura. Para cada um dos casos, simuladores específicos foram criados no intuito de observar as características pertinentes de cada estudo de caso. / Unmanned aerial vehicles (UAVs) are relatively new in civilian context, where many technologies and algorithms have been the focus at much research and development. Software engineering applied to this field has few approaches in relation to autonomous systems and intelligent behavior development, while multi-agent system and agent-oriented programming are being increasingly used. This work focuses on applying the paradigm of agent-oriented programming for the control of UAVs, in order to design a framework and use architecture, theory and agent oriented tools as a way to provide a more sophisticated abstraction for programming intelligent behaviors in UAVs . The main contribution of this work is an architecture that allows the use of the Jason platform to program multiagent system which can control teams of autonomous unmanned aerial vehicles. In this research, we propose the UAVAS - Unmanned Aerial Vehicles AgentSpeak model, which is a framework to program intelligent behaviors to UAVs and owns an abstraction model of manned aircraft to unmanned aerial vehicles. At the end, the survey was evaluated and validated by means of results from simulations in the implemented infrastructure. Two case studies were performed, with emphasis on inter-UAV communication and cooperation of team, and the another one focusing on mapping verifications of data signals sent to the infrastructure. For each case, specific simulators have been created in order to observe the relevant characteristics of each case study.

L’émergence de véhicules aériens sans pilote, généralement appelés drones, petits et bon marché favorise leur utilisation dans le domaine des applications civiles. Ces drones sont équipés de différents capteurs et ont la capacité de communiquer via des liaisons sans fil et ont la particularité de se déplacer librement dans l’espace, révolutionnant la gestion des applications de surveillance. Un réseau ad hoc de drones, Flying Ad hoc Networks (FANET) en anglais, est composé d’une flotte de drones autonomes et est utilisé lors de missions dans des environnements hostiles pour la surveillance ou l’inspection de sites dangereux ou inconnus. Les FANETs peuvent être également utilisés pour suivre et filmer des événements spéciaux comme une course de vélos ou un match de football, dans ce cas les liaisons doivent garantir un minimum de qualité. Les FANETs nécessitent une attention particulière en ce qui concerne l’économie d’énergie des UAV dont les ressources en énergie sont limitées, mais aussi d’être immunisés contre des attaques malveillantes. Au cours de cette thèse, nous nous sommes concentrés sur le problème de suivi d’une cible mobile utilisant une flotte de drones pour la filmer. Étant donné que la cible se déplace, les drones doivent la suivre en continu, et une liaison vers la station terrestre doit être disponible. Dans ce contexte, nous proposons une solution qui permet la coordination d’un ensemble de drones afin de maintenir un chemin optimal entre la cible et la station terrestre. Notre solution se révèle efficace en matière de gain en temps et en énergie. Nous avons également proposé une solution basée sur des protocoles hiérarchiques pour économiser plus d’énergie dans le processus de communication avec la station terrestre. Nous avons également développé une autre solution qui permet d’économiser plus d’énergie en forçant les nœuds égoïstes à participer dans le réseau et d’assurer le relais de paquets lorsqu’ils sont sollicités. En effet, si un nœud égoïste refuse de router des paquets d’autres nœuds, cela induit une charge supplémentaire pour le reste des nœuds du réseau. Nous avons validé l’apport de l’ensemble de nos solutions par évaluation de performances à l’aide de simulations. / The emergence of small and inexpensive Unmanned Aerial Vehicles (UAVs) promotes their use in several applications. UAVs are usually equipped with different sensors and have the ability to communicate via wireless connections. Their capability to fly freely in the space offers new opportunities to monitoring and tracking applications. A Flying Ad hoc Network (FANET) is composed of a fleet of autonomous UAVs and is used for monitoring applications in hostile environments, surveillance or site inspection. FANETs could also be used for filming special events such as bike races or soccer matches, so, the connections must guarantee a minimum of quality of service. In FANETs, saving energy of UAVs that have limited battery is very challenging and protecting the network from malicious attacks is even more difficult. In this thesis, we focus on tracking and filming a moving target using a fleet of UAVs. Since the target is moving, the UAVs have to follow it continuously, and a path to the ground station must be available. In this context, we propose an efficient solution that allows the coordination of the UAVs to maintain an optimal path between the target and the ground station. The proposed solution is time and energy efficient. We also propose a solution based on hierarchical protocols to save more energy in the communication process with the ground station. Another solution that allows energy saving is to force selfish nodes to participate in the network to route received packets towards their destination. Indeed, a selfish node is concerned only about its own welfare, refusing to route packets of other node, causing an extra charge for the rest of nodes in the network. We validate our solutions through simulation campaigns.

Data collection by autonomous mobile sensor arrays can be coupled with the use of drones which provide a low-cost, easily deployable backhauling solution. These means of collection can be used to organize temporary events (sporting or cultural) or to carry out operations in difficult or hostile terrain. The aim of this thesis is to propose effective solutions for communication between both mobile sensors on the ground and on the edge-to-ground link. For this purpose, we are interested in scheduling communications, routing and access control on the sensor / drone link, the mobile collector. We propose an architecture that meets the constraints of the network. The main ones are the intermittence of the links and therefore the lack of connectivity for which solutions adapted to the networks tolerant to the deadlines are adopted. Given the limited opportunities for communication with the drone and the significant variation in the physical data rate, we proposed scheduling solutions that take account of both the contact time and the physical flow rate. Opportunistic routing is also based on these two criteria both for the selection of relay nodes and for the management of queues. We wanted to limit the overhead and propose efficient and fair solutions between mobile sensors on the ground. The proposed solutions have proved superior to conventional scheduling and routing solutions. Finally, we proposed a method of access combining a random access with contention as well as an access with reservation taking into account the aforementioned criteria. This flexible solution allows a network of dense mobile sensors to get closer to the performance obtained in an oracle mode. The proposed solutions can be implemented and applied in different application contexts for which the ground nodes are mobile or easily adapted to the case where the nodes are static.

The work presented in this dissertation on piezoelectric inchworm motors (IWM) is part of a process to gain an understanding of the design, analysis and testing of this smart actuator technology. This work will form the foundation of what will hopefully lead to the realisation of a production-ready IWM design to be used in energy-scarce, battery-operated Unmanned Aerial Vehicles (UAVs), and forms part of a larger national drive to expand the UAV industry in South Africa. Although the principles used in the design of IWMs are well known, a new innovation is employed. A novel way to increase the force capacity of IWMs without compromising on the speed or displacement when compared to conventional methods is shown to be effective, and was used for the first time on IWMs. The use of a simple design equation is demonstrated to be useful in predicting the load limits and step displacements. Challenges of finding a correlation between predicted and measured performance values are discussed and solutions are presented. The history of IWMs and some background on piezoelectricity are given for the reader not familiar with these. The use of micro ridges on the clamp mechanisms is explored. The effects of the control signals on the mechanism of the motor are discussed in detail and some important comments on electrical controllers are made. The emphasis is on designing a strong motor that capitalises on the high-force density of piezoelectric material. / Dissertation (MEng)--University of Pretoria, 2014. / gm2014 / Mechanical and Aeronautical Engineering / unrestricted

Thesis submitted in compliance with the requirements for the Master's Degree in Technology: Department of Mechanical Engineering, Durban University of Technology, 2008. / The development of an evolutionary optimisation method and its application to the design of an advanced composite structure is discussed in this study. Composite materials are increasingly being used in various fields, and so optimisation of such structures would be advantageous. From among the various methods available, one particular method, known as Evolutionary Structural Optimisation (ESO), is shown here. ESO is an empirical method, based on the concept of removing and adding material from a structure, in order to create an optimum shape. The objective of the research is to create an ESO method, utilising MSC.Patran/Nastran, to optimise composite structures. The creation of the ESO algorithm is shown, and the results of the development of the ESO algorithm are presented. A tailfin of an aircraft was used as an application example. The aim was to reduce weight and create an optimised design for manufacture. The criterion for the analyses undertaken was stress based. Two models of the tailfin are used to demonstrate the effectiveness of the developed ESO algorithm. The results of this research are presented in the study. / M