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Employing concepts of the SDN paradigm to support last-mile military tactical edge networks / Empregando conceitos de redes definidas por software para apoio à redes táticas militares de última milhaZacarias, Iulisloi January 2018 (has links)
Em um futuro próximo, “dispositivos inteligentes” serão massivamente empregados em campos de batalha. Essa já é uma realidade, porém, o número de dispositivos utilizados em campos de batalha tende a aumentar em ordens de magnitude. As redes de comunicação de dados serão essenciais para transmitir os dados que esses dispositivos coletam e transformá-los em informações valiosas utilizadas como suporte à atuação humana. O suporte à tomada de decisão, ou mesmo níveis de autonomia, permitindo que estes dispositivos coordenem outros dispositivos, exigem comunicação contínua. Desafios relacionados à comunicação surgirão devido à dinamicidade do ambiente. A configuração da rede deve refletir decisões superiores automaticamente. A grande escala das redes conectando os altos escalões, tropas, veículos e sensores, aliada à falta de padronização dos dispositivos, tornará a integração destes desafiadora. Em um ambiente tão heterogêneo, muitos protocolos e tecnologias coexistirão. As redes de campo de batalha são um elemento de suma importância nas operações militares modernas e conceito de guerra centrada em rede é uma tendência sem volta e influencia desde os altos escalões até o controle de tropas Embora estudos tenham sido realizados nessa área, a maioria deles aborda redes estratégicas de alto nível e portanto não levam em conta as “redes táticas de última milha” (TEN), que compreendem dispositivos de comunicação com recursos limitados, como sensores ou ainda pequenos veículos aéreos não tripulados. Em uma tentativa de preencher esta lacuna, esse trabalho propõe uma arquitetura que combina conceitos dos paradigmas de redes definidas por software (SDN) juntamente com redes tolerantes à atraso/disrupçoes (DTN), para aplicação em redes táticas de última milha. O uso de SDN em cenários com nodos móveis é avaliado considerando uma aplicação de vigilância que utiliza streaming de vídeo e medidas de Qualidade de Experiência (QoE) de usuário são coletadas. Com base nos resultados obtidos, uma aplicação em conjunto dos conceitos de SDN e DTN é proposta, além disso abordamos a escolha do nodo que atuará como controlador SDN na rede. Os experimentos foram executados utilizando um emulador de redes. Apesar de pesquisas adicionais serem necessárias – considerado requisitos de segurança, por exemplo – os resultados foram promissores e demonstram a aplicabilidade destes conceitos no cenários das TENs. / The future battlefield tends to be populated by a plethora of “intelligent things”. In some ways, this is already a reality, but in future battlefields, the number of deployed things should be orders of magnitude higher. Networked communication is essential to take real advantage of the deployed devices on the battlefield, and to transform the data collected by them into information valuable for the human warfighters. Support for human decision making and even a level of autonomy, allowing devices to coordinate and interact with each other to execute their activities in a collaborative way require continuous communication. Challenges regarding communication will arise from the high dynamics of the environment. The network adaption and management should occur autonomously, and it should reflect upper-level decisions. The large scale of the network connecting high-level echelons, troops on the field, and sensors of many types, beside the lack of communication standards turn the integration of the devices more challenging. In such a heterogeneous environment, many protocols and communication technologies coexist. This way, battlefield networks is an element of paramount importance in modern military operations Additionally, a change of paradigm regarding levels of autonomy and cooperation between humans and machines is in course and the concept of network-centric warfare is a no way back trend. Although new studies have been carried out in this area, most of these concern higher-level strategic networks, with abundant resources. Thus, these studies fail to take into account the “last-mile Tactical Edge Network (TEN) level,” which comprises resource constrained communication devices carried by troopers, sensor nodes deployed on the field or small unmanned aerial vehicles. In an attempt to fill this gap, this work proposes an architecture combining concepts from software-defined networking (SDN) paradigm and the delay-tolerant approach to support applications in the last-mile TEN. First, the use of SDN in dynamic scenarios regarding node positioning is evaluated through a surveillance application using video streaming and Quality of Experience (QoE) measures are captured on the video player. We also explore the election of nodes to act as SDN Controllers in the TEN environment. The experiments use emulator for SDN with support to wireless networks. Further investigation is required, for example, considering security requirements, however the results are promising and demonstrate the applicability of this architecture in the TEN network scenario.
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Quantifying Computer Vision Model Quality Using Various Processing TechniquesRuggles, Samantha Anna 01 June 2016 (has links)
Recently, the use of unmanned aerial vehicles (UAVs) has increased in popularity across several industries. Most notable, however, is the impact that this technology has had in research at academic institutions worldwide. As the technology for UAVs has improved, with that comes easier to operate, more accessible equipment. UAVs have been used in various types of applications and are quickly becoming a preferred method of studying and analyzing a site. Currently, the most common use of a UAV is to monitor a location of interest to a researcher that is difficult to gain access to otherwise. The UAV can be altered to meet the needs of any given project and this versatility has contributed to their popularity. Often, they are equipped with a type of remote sensor that can gather information in the form of images, sounds, heat, or light. Once data has been gathered from a site, it is processed and modified, allowing it to be studied and analyzed. A process known as Structure from Motion (SfM) creates a 3D digital terrain model from camera images captured through the use of a UAV. SfM is a common method of processing the vast amount of images that are taken at a site and the 3D model that it creates is a helpful resource for analysis. These digital models, while useful, are oftentimes created at an unknown accuracy. This research presents a comparative study of the accuracies obtained when different parameters are applied during the SfM process. The results present a comparison of the time required to process a particular model and the accuracy that the model had. Depending on the application and type of project, a desired level of accuracy can be obtained in the presented amount of time. This particular study used a landslide as the site of interest and captured the imagery using a helicopter UAV.
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Fault-Tolerant Adaptive Model Predictive Control Using Joint Kalman Filter for Small-Scale HelicopterCastillo, Carlos L 03 November 2008 (has links)
A novel application is presented for a fault-tolerant adaptive model predictive control system for small-scale helicopters. The use of a joint Extended Kalman Filter, (EKF), for the estimation of the states and parameters of the UAV, provided the advantage of implementation simplicity and accuracy. A linear model of a small-scale helicopter was utilized for testing the proposed control system. The results, obtained through the simulation of different fault scenarios, demonstrated that the proposed scheme was able to handle different types of actuator and system faults effectively. The types of faults considered were represented in the parameters of the mathematical representation of the helicopter.
Benefits provided by the proposed fault-tolerant adaptive model predictive control systems include: The use of the joint Kalman filter provided a straightforward approach to detect and handle different types of actuator and system faults, which were represented as changes of the system and input matrices. The built-in adaptability provided for the handling of slow time-varying faults, which are difficult to detect using the standard residual approach. The successful inclusion of fault tolerance yielded a significant increase in the reliability of the UAV under study.
A byproduct of this research is an original comparison between the EKF and the Unscented Kalman Filter, (UKF). This comparison attempted to settle the conflicting claims found in the research literature concerning the performance improvements provided by the UKF. The results of the comparison indicated that the performance of the filters depends on the approximation used for the nonlinear model of the system. Noise sensitivity was found to be higher for the UKF, than the EKF. An advantage of the UKF appears to be a slightly faster convergence.
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Coherent design of uninhabited aerial vehicle operations and control stationsGonzalez Castro, Luis Nicolas 22 May 2006 (has links)
This work presents the application of a cognitive engineering design method to the design of operational procedures and ground control station interfaces for uninhabited aerial vehicles (UAVs). Designing for UAV systems presents novel challenges, both in terms of selecting and presenting adequate information for effective teleoperation, and in creating operational procedures and ground control station interfaces that are robust to a range of UAV platforms and missions. Creating a coherent set of operating procedures, automatic functions and operator interfaces requires a systematic design approach that considers the system and the mission at different levels of abstraction and integrates the different element of the system.
Several models are developed through the application of this cognitive engineering method. An analysis of the work of operating a UAV creates an abstraction decomposition space (ADS) model. The ADS helps identify the control tasks needed to operate the system. A strategies analysis then identifies methods for implementing these control tasks. The distribution of activities and roles between the human and automated components in the system is then considered in a social organization and cooperation analysis.
These insights are applied to the design of coherent sets of operational procedures, ground control station interfaces and automatic functions for a specific UAV in support of a continuous target surveillance (CTS) mission. The importance of the coherence provided by the selected design method in the design of UAV operational procedures and ground control station interfaces is analyzed through a human in the loop simulation experiment for this mission. The results of the simulation experiment indicate that UAV controllers using coherently designed elements achieve significantly higher mission performance and experience lower workloads than those that when using incoherently matched elements.
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Modeling and Analysis of Cooperative Search SystemsPortilla, Carlos A. 08 July 2010 (has links)
The analysis of performance gains arising from cueing in cooperative search
systems with autonomous vehicles has been studied using Continuous Time Markov
Chains; where the search time distributions are assumed to follow the exponential
distributions. This work proposes the use of Petri Nets to model and analyze these
systems. The Petri Net model considers two types of autonomous vehicles: a search-only
vehicle and n search-engage vehicles. Specific performance metrics are defined to
measure system’s performance. Through simulation, it is shown that the search time with
stationary targets and cues that provide exact target location follows a triangular
distribution. A methodology for approximating general distributions and incorporating
them into the Petri Net model for performance analysis is presented.
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Analysis of VTOL MAV use during rescue and recovery operations following Hurricane KatrinaPratt, Kevin S 01 June 2007 (has links)
There can be little doubt that Hurricane Katrina will always be remembered for the damage and devastation it caused. But it also provided the first opportunity for MAVs to be used and evaluated during Search and Rescue (SAR) as well as recovery operations. Researchers from The Center for Robot-Assisted Search And Rescue (CRASAR) made two separate deployments to areas affected by Hurricane Katrina: one during initial SAR operations and a second deployment during recovery operations 90 days later. Using data and observations from both of these deployments, this work draws four key findings about semi-autonomous Miniature UAV (MAV) operations in urban environments. These findings are intended to guide future MAV research as well as serve as a roadmap for the evolution from semi-autonomous to fully autonomous MAV capabilities. These findings are as follows: the minimum useful standoff distance from inspected structures is 2-5 m, omni-directional sensor capabilities are needed for obstacle avoidance, GPS waypoint navigation is unnecessary, and that these operations currently require three operators for one MAV.
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Advancing Weapons Technology and the Future of Warfare: Strategic, Legal and Ethical PerspectivesGuest, Jenna Kate January 2011 (has links)
As the role of technology within warfare continues to increase, it is important to investigate whether or not the consequences of these weapons are being adequately considered. The use of new weapons technologies, such as Unmanned Combat Aerial Vehicles and Precision Guided Munitions, have been both praised and condemned within the war in Afghanistan. Although praised as saving civilian lives due to the precision capabilities of the weaponry there are consistent civilian deaths attributed to these weapons systems. This study examines debates regarding new weapons technologies that have been utilised during the war in Afghanistan. Current literature regarding emerging weapons technology is examined in order to identify key debates. The literature was recognised as falling predominantly within three perspectives - strategy, law and ethics. By identifying the key debates within each perspective it is possible to identify where these debates overlap or diverge. This research concludes that the introduction of counterinsurgency strategy to modern warfare has led to an increasing concern with the ethical and legal dimensions of the debate surrounding new weapons technology.
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Vision based 3D obstacle detection using a single camera for robots/UAVsShah, Syed Irtiza Ali 01 July 2009 (has links)
This thesis aims at detecting obstacles using a single camera in an unknown 3D world for 3D motion of the robot/UAV. Obstacle detection is a pre-requisite for collision-free motion of robots/UAVs. Most of the research in this area has been for 2D motion of the ground robots and with active sensors e.g Laser range finders, Ultrasonic sensors, SONAR, RADAR etc. The passive camera based research has mostly been done either using triangulation/stereo vision (using more than one camera), or, developing an expectation map pre-hand, of the world and comparing it with the new image data.
In contrast, this thesis, aims at finding solution of the problem using just a single camera in a perfectly unknown world. This requirement is based on the fact that at least a single camera would be carried by almost all robots/UAVs anyway in foreseeable future. Hence the attempt is to use the same camera for obstacle detection and avoidance task as well, so as to come up with a low cost and light weight solution, in order to facilitate building miniature robots/UAVs.
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Employing concepts of the SDN paradigm to support last-mile military tactical edge networks / Empregando conceitos de redes definidas por software para apoio à redes táticas militares de última milhaZacarias, Iulisloi January 2018 (has links)
Em um futuro próximo, “dispositivos inteligentes” serão massivamente empregados em campos de batalha. Essa já é uma realidade, porém, o número de dispositivos utilizados em campos de batalha tende a aumentar em ordens de magnitude. As redes de comunicação de dados serão essenciais para transmitir os dados que esses dispositivos coletam e transformá-los em informações valiosas utilizadas como suporte à atuação humana. O suporte à tomada de decisão, ou mesmo níveis de autonomia, permitindo que estes dispositivos coordenem outros dispositivos, exigem comunicação contínua. Desafios relacionados à comunicação surgirão devido à dinamicidade do ambiente. A configuração da rede deve refletir decisões superiores automaticamente. A grande escala das redes conectando os altos escalões, tropas, veículos e sensores, aliada à falta de padronização dos dispositivos, tornará a integração destes desafiadora. Em um ambiente tão heterogêneo, muitos protocolos e tecnologias coexistirão. As redes de campo de batalha são um elemento de suma importância nas operações militares modernas e conceito de guerra centrada em rede é uma tendência sem volta e influencia desde os altos escalões até o controle de tropas Embora estudos tenham sido realizados nessa área, a maioria deles aborda redes estratégicas de alto nível e portanto não levam em conta as “redes táticas de última milha” (TEN), que compreendem dispositivos de comunicação com recursos limitados, como sensores ou ainda pequenos veículos aéreos não tripulados. Em uma tentativa de preencher esta lacuna, esse trabalho propõe uma arquitetura que combina conceitos dos paradigmas de redes definidas por software (SDN) juntamente com redes tolerantes à atraso/disrupçoes (DTN), para aplicação em redes táticas de última milha. O uso de SDN em cenários com nodos móveis é avaliado considerando uma aplicação de vigilância que utiliza streaming de vídeo e medidas de Qualidade de Experiência (QoE) de usuário são coletadas. Com base nos resultados obtidos, uma aplicação em conjunto dos conceitos de SDN e DTN é proposta, além disso abordamos a escolha do nodo que atuará como controlador SDN na rede. Os experimentos foram executados utilizando um emulador de redes. Apesar de pesquisas adicionais serem necessárias – considerado requisitos de segurança, por exemplo – os resultados foram promissores e demonstram a aplicabilidade destes conceitos no cenários das TENs. / The future battlefield tends to be populated by a plethora of “intelligent things”. In some ways, this is already a reality, but in future battlefields, the number of deployed things should be orders of magnitude higher. Networked communication is essential to take real advantage of the deployed devices on the battlefield, and to transform the data collected by them into information valuable for the human warfighters. Support for human decision making and even a level of autonomy, allowing devices to coordinate and interact with each other to execute their activities in a collaborative way require continuous communication. Challenges regarding communication will arise from the high dynamics of the environment. The network adaption and management should occur autonomously, and it should reflect upper-level decisions. The large scale of the network connecting high-level echelons, troops on the field, and sensors of many types, beside the lack of communication standards turn the integration of the devices more challenging. In such a heterogeneous environment, many protocols and communication technologies coexist. This way, battlefield networks is an element of paramount importance in modern military operations Additionally, a change of paradigm regarding levels of autonomy and cooperation between humans and machines is in course and the concept of network-centric warfare is a no way back trend. Although new studies have been carried out in this area, most of these concern higher-level strategic networks, with abundant resources. Thus, these studies fail to take into account the “last-mile Tactical Edge Network (TEN) level,” which comprises resource constrained communication devices carried by troopers, sensor nodes deployed on the field or small unmanned aerial vehicles. In an attempt to fill this gap, this work proposes an architecture combining concepts from software-defined networking (SDN) paradigm and the delay-tolerant approach to support applications in the last-mile TEN. First, the use of SDN in dynamic scenarios regarding node positioning is evaluated through a surveillance application using video streaming and Quality of Experience (QoE) measures are captured on the video player. We also explore the election of nodes to act as SDN Controllers in the TEN environment. The experiments use emulator for SDN with support to wireless networks. Further investigation is required, for example, considering security requirements, however the results are promising and demonstrate the applicability of this architecture in the TEN network scenario.
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Controle para um veículo aéreo não tripulado do tipo quadricópteroDantas, Flávia Elionara Freire 17 February 2017 (has links)
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Previous issue date: 2017-02-17 / Research on Unmanned Aerial Vehicles (UAVs) has been intensified since the 2000s with the
aim of replacing manned vehicles. Its maneuverability makes it capable of handling various
types of applications such as surveillance of a particular area, inspection of structures, in
difficult to access environments, among others. When the first research began, this type of
aerial vehicle was only used for military applications, but at the moment they are studied for
other applications; the studies focus on control techniques for stability and flight autonomy.
This work aimed the development of an altitude control and attitude of a UAV type quadrotor;
the implementation was carried out on the Arduino platform and the flight tests indoors.
Design of stability and height control, comparisons between two types of height control, PID
(Proportional-Integral-Derivative) and Fuzzy in a Simulink® / MATLAB environment were
performed / anos 2000, com o objetivo de substituir os veículos tripulados. Sua manobrabilidade o torna
apto a lidar com diversos tipos de aplicações como vigilância de uma determinada área,
inspeção de estruturas, em ambientes de difícil acesso, entre outros. Quando as primeiras
pesquisas iniciaram, esse tipo de veículo aéreo era usado apenas para aplicações militares,
mas atualmente são estudados para outras aplicações; os estudos se concentram em técnicas
de controle para estabilidade e autonomia dos voos. Este trabalho objetiva o desenvolvimento
de um controle de altitude e atitude de um VANT do tipo quadricóptero; a implementação foi
realizada na plataforma Arduino e os testes de voo em ambientes fechados. Foi realizado o
controle de estabilidade e de altura, comparações entre dois tipos de controle de altura, PID
(Proporcional-Integral-Derivativo) e Fuzzy em ambiente Simulink®/MATLAB / 2017-06-27
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