The aim of the present study is to explain what where the driving forces behind the development of antisubmarine warfare skill on Swedish sea operational helicopters during the time 1980-92. The study is done by using two different perspective, based on Graham Allison scientific explanation models found in his book Essence of Decision. In the study the perspectives are named “rational actor” and “governmental politics”. The purpose is to investigate if respective model can explain the development of antisubmarine warfare skill on Swedish helicopters during the previously mentioned timeframe. The result of the study is that by using the rational actor perspective the development of anti submarine warfare can be explained in a large extent. The study proves that there were a well-defined threat and that consensus was that this threat would be met i.e. with anti submarine warfare resources. It cannot be demonstrated that the helicopter and the development of its anti submarine warfare capability was the single most suitable option. By using the model governmental politics, the development is not significantly explained because no internal differences of large extent have been demonstrated. The model contributes rather to illuminate the actors and factors that shaped their actions. If the models are used as complement to each other a wider perspective of what has happened is shown, but the explanation is not strengthened. / Syftet med uppsatsen är att studera de drivkrafter som låg bakom utvecklingen av den svenska ubåtsjaktförmågan på sjöoperativ helikopter under tidsperioden 1980-92. Studien genomförs med hjälp av två perspektiv vilka är baserade på Graham Allisons samhällsvetenskapliga modeller, och dennes bok Essence of Decision. I arbetet benämns perspektiven rationell aktörsmodell respektive maktspelsmodell. Ambitionen är att undersöka om respektive modell kan förklara utvecklingen av ubåtsjaktförmågan på sjöoperativ helikopter under nämnda period. Resultatet av studien är att med hjälp av den rationella aktörsmodellen kan bakomliggande drivkrafter till utvecklingen av ubåtsjaktförmågan i stor utsträckning påvisas. Studien påvisar att det fanns ett väl definierat hot samt att enighet rådde att detta hot skulle bemötas, d.v.s. med ubåtsjaktresurser. Dock kan inte påvisas att helikopter och utvecklingen av dess ubåtsjaktförmåga var det enskilt lämpligaste alternativet. Med hjälp av maktspelsmodellen kan orsakerna till utvecklingen inte nämnvärt förklaras eftersom inget maktspel av större omfattning har påvisats. Den senare modellen bidrar snarare till att belysa aktörer och faktorer som formade deras agerande. Nyttjar man modellerna som komplement till varandra ges en bredare bild av skeendet men förklaringen av bakomliggande faktorer stärks inte.

The thesis deals with the current state of how air services are used within the Integrated Rescue System (IRS); it analyzes the level of equipment, possibilities of use and deployment of such technologies in emergency situations; and evaluates technical, qualitative and quantitative levels of all means that air services use in emergency situations. The thesis also puts emphasis on the analysis of dislocation of these means, its advantages and suitability when scrutinized in terms of quality, speed and efficiency of their deployment in emergency security situations, rescue operations, or their deployment during natural disasters. The outcome of the thesis comprises of proposals how to comprehensively amend applicable laws; and of conclusions that may help instigate discussion on the observed shortfalls, and how to increase efficiency, economy, and logical scheme leading to a timely response in emergency situations. The empirical part of thesis includes quantitative and qualitative researches which scrutinized two research corpuses. Tackling the first research corpus, the author used questionnaires to collect data technically. The questionnaires were aimed at members of the basic units of the IRS components. The outcomes of the questionnaires are shown in graphs. Tackling the second research corpus, the author held semi-structured interviews with expert representatives of subjects that provide air services within the IRS. Assessment of the outcomes was based on the transcriptions of the interviews which involved inserting the data into tables summarizing the most important outcomes of the research. Subsequently, these outcomes were used to identify the most important theses which were based on the answers provided by the respondents to research questions. The research also included an analysis of the available legal standards and documents related to the use of air services to provide efficient intervention, their assessment and identification of some criteria for de lege ferenda proposals to comprehensively amend selected laws. In conclusion, it was found out that there is poor awareness of possibilities how to use air services among the members of the basic units in individual IRS components, which results in insufficient deployment of Air Services while carrying out interventions.

Med början på år 1995 slogs Flygvapnets-, Arméns- och Marinflygets respektive helikopterförband samman till en gemensam helikopterflottilj sorterandes under Flygvapnet. Äldre helikoptersystem byttes ut mot nya uppdaterade system för att bättre klara dagens uppgifter parallellt med att efterfrågan har ökat nationellt såväl som internationellt. Samtidigt som en statlig utredning säger att understöd med helikopter är av stor betydelse för Försvarsmaktens framtida användbarhet så har flera omorganisationer skett inom myndigheten, vilket riskerar att hämma effektiviteten.  Hur lämplig är Försvarsmaktens nuvarande helikopterorganisation när det gäller helikoptersamövning mellan Helikopterbataljonen och övriga förband? Studien visar att dagens Försvarsmakt, där efterfrågan på helikoptrarna är större än de tillgängliga resurserna, använder sig av ett system med både styrningar från högre chef såväl som önskemål från förbanden. Detta organisationsval stämmer väl överens med de antaganden, hämtade ur Bolman & Deals teori Det strukturella perspektivet, som har utgjort arbetets teoretiska grund. I arbetet framkommer även att det saknas en försvarsmaktsgemensam erfarenhetsdatabas för dessa övningar vilket riskerar att utgöra en friktion i kunskapsspridningen mellan förbanden. / Beginning in 1995, the Swedish Air force’s, Army´s and Navy´s respective helicopter units merged into one Helicopter Wing belonging to the Air force.  Older helicopter systems were exchanged to new, more updated systems with higher capability to cope with new demands. Today the use of helicopters has increased both nationally and internationally. While a state investigation says that the use of helicopters has a big role for the future use of the Swedish military, has several reorganizations taken place. Changes that may inhibit the efficiency of the Swedish Armed Forces. How suitable is today´s helicopter organization within the Swedish Armed Forces regarding to joint exercises between the Helicopter Battalion and other units? The study shows that today's organization, where the demand for helicopters is greater than the available resources, uses a hierarchical system that uses both directives from higher levels as well as requests from the different units. This organizational construction is consistent with the assumptions taken from Bolman & Deals theory Structural Framework, which has formed the theoretical ground for the study. The work also reveals the lack of a joint experience database for these exercises which might impede the spread of knowledge between the units.

Tidigare forskning har visat att svenska stridspiloter har uppvisat en anmärkningsvärt hög förekomst av depressions- och ångestsymptom, vilket både riskerar att minska effektiviteten hos de svenska luftstridskrafterna och kan innebära en fara för flygsäkerheten. Detta arbete syftar till att underlätta beslutsfattandet kring problemet genom att skapa ett bättre underlag för att förstå de bakomliggande orsakerna. Studien undersöker när under karriären symptomen uppkommer samt jämför mellan olika pilotkategorier för att skapa en bättre förståelse för hur problemen uppstår och därmed vilka åtgärder som kan vidtas för att förhindra detta. En kvantitativ enkätundersökning användes för att undersöka förekomsten av depressions- och ångestsymptom bland svenska strids-, transport- och helikopterpiloter under deras första fem utbildningsår. Enkäten baserades på HADS-skalan och skickades till 158 personer, varav hälften var piloter. Resultatet av studien indikerar att den höga förekomsten av depressions- och ångestsymptom uppkommer senare i stridspilotkarriären. Stridspiloterna uppvisade dessutom en lägre förekomst av depressions- och ångestsymptom än en icke-flygande kontrollgrupp. Dessa resultat pekar i sin tur mot att miljöfaktorerna spelar en större roll än de genetiska faktorerna vid uppkomsten av symptomen. Författarens slutsats är att förekomsten av depressioner och ångestsyndrom bland stridspiloterna är påverkbar, och några lämpliga åtgärder föreslås. / Earlier research has shown that Swedish fighter pilots have displayed a remarkably high prevalence of symptoms of depression and anxiety, which could lead to a reduction in the effectiveness of the Swedish Air Force as well as compromising flight safety. The purpose of this study is to aid in the decision making process revolving this problem by providing more substantial material in order to better understand the underlying causes. The study investigates the emergence of the symptoms and compares different pilot categories with each other to create a better understanding of how these problems arise and by such deduce which measures can be taken to prevent this.   A quantitative questionnaire survey was used to investigate the prevalence of symptoms of depression and anxiety among fighter, transport and helicopter pilots during their first five years of training. The questionnaire was based on the HADS-scale and was sent to 158 persons, half of them pilots. The result of the study indicates that the high prevalence of symptoms of depression and anxiety is something that emerges later on in the fighter pilot’s career. The fighter pilots in this study displayed a lower prevalence of symptoms of depression and anxiety than a non-flying control group. These results in turn indicate that the environmental factors play a larger part than the genetic factors in the emergence of the previously mentioned symptoms. The author of this work comes to the conclusion that there is indeed a possibility of affecting the prevalence of depressions and anxiety syndromes among Swedish fighter pilots and some appropriate counter measures are proposed.

O objetivo deste trabalho é investigar o controle ativo de vibração em uma pá inteligente de helicóptero. O desenvolvimento de materiais inteligentes para trabalharem como sensores e atuadores apresentam uma nova alternativa no controle de vibração. A pá de helicóptero é modelada pelo método dos elementos finitos, considerando os movimentos de batimento, flexão no plano de rotação, estiramento axial e torção. O modelo da pá considera também ângulo de torção geométrica, não coincidência entre os eixos, elástico e do centro de gravidade das seções transversais e material isotrópico. O modelo matemático é desenvolvido, e nele é incorporado atuadores piezelétricos distribuídos ao longo da envergadura da pá. O controle ativo de vibração é baseado no controle individual da pá na condição de vôo pairado. As matrizes de elementos finitos são obtidas pelo método de energia e um procedimento de linearização é aplicado às equações resultantes. O carregamento aerodinâmico linearizado é calculado para a condição de vôo pairado e a representação no espaço de estados é usada para o projeto de um controlador. Usou-se a técnica de atribuição da autoestrutura por realimentação de saída no modelo de ordem reduzida, resultado da aplicação do método da expansão por frações parciais. As simulações do modelo em malha aberta e fechada, exibiu boas qualidades de resposta, o que mostra que o controle ativo é uma boa alternativa para a redução de vibrações em helicópteros. / The objective of this work is to investigate the performance of a smart helicopter blade. Developments on smart materials for both sensing and/or actuation have provided a novel alternative in vibration control. The helicopter blade is modeled by the finite element method, considering the motions of flapping, lead-lagging, axial stretching, and torsion. The blade model also considers a pretwist angle, offset between mass and elastic axes, and isotropic material. The helicopter blade mathematical model allows the incorporation of piezoelectric actuators distributed along the blade span. The active vibration control is based on the premise of individual blade control and the investigation is carried out for hovering flight condition the finite element matrices are obtained by energy methods and a linearization procedure is applied to the resulting expressions. The linearized aerodynamic loading is calculated for hover and the state-space approach is used to design the control law. The eigenstructure assignment by output feedback is used in the blade-reduced model resulting from the application of the expansion method by partial fractions. The simulations for open and closed-loop systems are presented, having exhibited good response qualities, which shows that output feedback is a good alternative for smart helicopter blade vibration attenuation.

Este trabalho trata da coordenação de robôs heterogêneos que consiste em um robô helicóptero e em múltiplos robôs móveis com rodas, de modo que estes sigam um líder. Para atingirmos este objetivo, neste trabalho desenvolve-se a estimação da atitude e posição de um robô utilizando filtros robustos. Os filros realizam a fusão dos sinais de uma unidade de medida inercial de baixo custo e de um receptor GPS (Global Positioning System) considerando um modelo de corpo rígido formulado em termos de quatérnios. Resultados experimentais são apresentados baseados em um estudo comparativo entre os filtros robustos e o filtro de Kalman. Desenvolve-se o controle de um robô móvel com rodas deslizantes e de um robô helicóptero. Para realizar o controle robusto utilzia-se um regulador robusto recursivo. Simulaçõoes do robô móvel com rodas deslizantes e do robô helicóptero são apresentadas utilizando os parâmetros de um robô móvel Pioneer 3AT e de um robô helicóptero RMAX. Desenvolve-se também um mini robô helicóptero e uma base de movimento para realização de testes de controle do mini robô helicóptero constiste de um mini helimodelo e de um piloto automático baseado em um microprocessador com conectividade Wi-Fi, uma unidade de medida inercial e uma placa de controle de servos motores. E por fim, desenvolve-se a coordenação de robôs heterogêneos de modo que estes sigam um líder. Para isto é utilziado um controlador descentralizado e cooperativo cuja finalidade é gerar trajetórias de referência para que os robôs heterogênos se movimentem em formação rígida. / This research deals with the coordination of the heterogeneous robots, consisting of a robotic helicopter and multiple uheeled mobile robots, to achieve this aim this work develops the estimation of attitude, heading and positions of a robot based on robust filters. The filters perform the fusion of the signals of a low-cost inertial measurement unit and a GPS (Global Positioning System) receiver considering a rigid body model formulated in terms of quaternions. Experimental results are presented based on a comparative study of the robust filters and Kalman filter. It develops a robust control scheme of a ski-steering mobile robot and a robotic helicopter. The robust control is performed through a the robust recursive regulator. Simulations of the skid-steering mobile robot and a robotic helicopter are presented using the parameters of a Pioneer 3AT and a robotic helicopter RMAX. It also develops a mini robotic helicopter and a motion base to perform control test of a mini robotic helicopter. The mini robotic helicopter consists of a mini helicopter TREX 450 XL and an autopilot based on a microprocessor with Wi-Fi, an inertial measurement unit a servo control board. To finish, it develops the coordination of the heterogeneous robots in order to perform a leader strategy based on the concept of rigid formation.

La motivation qui a initié le projet de recherche ANR « Démonstrateur Gun Launched Micro Air Vehicle » est le besoin d’avoir un engin portatif qui permettrait d’obtenir rapidement des images d’une zone d’intérêt située à quelques centaines de mètres, avec la possibilité de pouvoir observer l’intérieur des bâtiments à travers leurs fenêtres ou en allant les explorer directement. Pour répondre à ce besoin, l’Institut franco-allemand de recherche de St Louis a eu l’idée de lancer un minidrone hélicoptère avec un canon. Le GLMAV, sous la forme d’un projectile, est lancé à partir d‘un tube portable à une distance de 500 m et une altitude de 100 m, où il pourra commencer à transmettre des images de la zone à observer. L’utilisation d’un système hybride projectile/minidrone a deux principaux avantages : cela permet d’augmenter l’autonomie du drone, et les premières images de la zone d’intérêt sont obtenues très rapidement. Au cours de cette thèse, nous nous sommes intéressés à la phase de transition, passer d’un projectile à un mini hélicoptère. Un modèle aérodynamique détaillé du GLMAV a été obtenu sur toute son enveloppe de vol. En prenant en compte les difficultés rencontrées lors de la phase de transition (perturbations des capteurs dues à l’accélération de 2500g au lancement, conditions initiales variables), nous avons développé une stratégie de commande, et une loi de commande en vitesse basée sur la technique du backstepping. Cette stratégie de commande a été validée en simulation. La loi de commande en orientation a été validée sur le prototype du GLMAV. Des travaux sur le flux optique, pour obtenir les vitesses latérales, ont été commencés. / The motivation that initiated the ANR research project "Démonstrateur Gun Launched Micro Air Vehicle" is the need to have a portable system which would permi tto quickly obtain images of an zone of interest placed at some hundred of meters, with the possibility to observe inside buildings either by their windows or by going inside them.To answer this need, the French-German Research Institute of St Louis got the idea o fusing a gun launched rotorcraft-MAV. The GLMAV, in its projectile form, is launched from a portable launching tube to a distance of 500m and a height of 100m, where it will collect and transmit visual information from the scene. The use of a projectile/rotorcraft-MAV hybrid system has two main advantages : it allows extending the MAV range,and the first images of the interest zone are obtained very quickly. During this PhD, we studied the transition phase, the passage from a projectile to a rotorcraft-MAV. A detailed aerodynamic model of the GLMAV has been obtained over his whole flight envelope. Taking into account the difficulties encountered during the transition phase (perturbation of the sensors caused by the 2500g acceleration at the launch, varying initial conditions),we developed a control strategy, and a velocity control law based on the backstepping methodology. This control strategy has been validated in simulation. The attitude control law has been validated on the GLMAV prototype. Studies on optical flow, to obtain the lateral velocities of the GLMAV, have been started.

La stabilisation et l’automatisation du vol de tout véhicule aérien nécessite la mise en oeuvre d’algorithmes de commande. La synthèse et la simulation des lois de commande reposent sur un modèle mathématique du véhicule, qui doit être de complexité et de précision appropriées. Cette thèse présente une méthodologie complète d’identification appliquée à un hélicoptère coaxialminiature. L’étude théorique de son comportement en vol permet d’établir plusieurs modèles basés sur la mécanique du vol, qui diffèrent par les phénomènes aérodynamiques pris en compte. Ils sont identifiés, comparés et validés grâce à des données de vol, mettant en évidence l’importance de certains phénomènes dans la précision du modèle. Différentes lois de commande sont alors étudiées et évaluées en simulation puis par des expérimentations sur un prototype. Les résultats obtenus sont conformes aux simulations numériques, validant ainsi l’ensemble de la démarche. / Control algorithms are at the heart of the stability and automatic flight capabilities of any aerial vehicle. Synthesis and simulation of control laws are based on a mathematicalmodel of the vehicle, which must be a trade-off between simplicity and accuracy. This work presents a complete system identification methodology applied on a miniature coaxial helicopter. Based on flight mechanics and aerodynamics, several models are built. They differ in the aerodynamic phenomena taken into account. They are identified, compared and validated thanks to flight data, highlighting important phenomena in the accuracy of the model. Several flight control strategies are then studied and evaluated through simulations and experiments with a prototype. The results are in accordance with numerical simulations, thus validating the whole approach.

The main content of this master's is desing of analysis and comparison of technical-operational parameters of aircrafts and UAVs used for aerial works. This theme attend to basic factors that affect selection of aeronautical technics used for aeriál works, also ekonomics and technical calculation.

Ce travail de thèse porte sur les propriétés de stabilité des tourbillons hélicoïdaux, structures que l'on retrouve notamment dans le sillage des rotors d'hélicoptères et d'éoliennes.Dans une première partie, le développement spatio-temporel de l'instabilité d'appariement est caractérisé à l'aide d'un code numérique pseudo-spectral pour une allée infinie d'anneaux tourbillonnaires. On montre que ce modèle axisymétrique d'écoulement est en effet une bonne approximation du système hélicoïdal dans la limite des grands rayons et petits pas d’hélice. Dans ces conditions, et en utilisant un adimensionnement judicieux, on obtient également que le résultat théorique pour le taux de croissance spatio-temporel obtenu pour une double allée de tourbillons ponctuels s’avère être une bonne prédiction pour le cas hélicoïdal.Dans une seconde partie, on décrit comment un ou plusieurs tourbillons hélicoïdaux ont pu être générés de façon très peu perturbée à l’aide de modèles réduits de rotors dans le canal hydrodynamique du laboratoire. Grâce à l’introduction de perturbations d’amplitudes et de fréquences soigneusement contrôlées, le taux de croissance de l’instabilité d’appariement a pu être mesuré et comparé aux résultats théoriques. L’évolution non linéaire de ces perturbations ainsi que d’autres modes instables, à plus petites longueurs d’onde, ont également pu être observés expérimentalement pour la première fois.Enfin, ces résultats ont été appliqués au cas des rotors d’hélicoptères pour la prédiction du régime de Vortex Ring State (VRS) et à la transition vers la turbulence du sillage des éoliennes. / This thesis is devoted to the stability properties of helical vortices, which are of interest for applications such as helicopter and wind turbine wakes.In a first part, the spatio-temporal development of the pairing instability is characterised for an infinite array of vortex rings, using a pseudo-spectral numerical code. We show that this axisymmetric flow model is indeed a good approximation of the helical system in the limit of large helix radius and small pitch. Under these assumptions, and by using appropriate dimensionless variables, we also show that the theoretical result concerning the spatio-temporal growth rate for a double row of point vortices represents a good prediction for the helical case.In a second part, we describe how one or several helical vortices were generated in a carefully controlled way using small-scale rotor models in the water channel of the laboratory. Introducing perturbations with well-defined amplitudes and frequencies, the growth rate of the pairing instability could be measured experimentally and compared to theoretical predictions. The non-linear evolution of these perturbations, as well as other unstable modes of smaller wavelengths, were also observed experimentally for the first time.Finally, these results were applied to helicopter wakes for the prediction of the Vortex Ring State (VRS) regime and to the transition to turbulence in wind turbine wakes.