Studies of the permanent magnet dc machine

A hybrid drive of an unmanned aerial vehicle uses two mechanically coupled drives. In one of the drives, an electrical machine is used. Its role is not only limited to a motoring operation, e.g. during achieving the flight ceiling. The electric machine changes its operation into generating after reaching the flight ceiling, this allows not only meeting current electrical energy demands but also battery recharging. This paper presents the results of laboratory tests of a BLDC machine in motoring and generating operation. Mechanical characteristics of the motor for different supply voltages and external characteristics for generator were determined. The possible energy conversion efficiencies for both motoring and generating operations were determined

Optimized Endpoint Delivery Via Unmanned Aerial Vehicles

Unmanned Aerial Vehicles (UAVs) are remotely piloted aircraft with a range of varying applications. Though early adoption of UAVs focused on military applications, surveillance, photography, and agricultural applications are presently on the rise. This work aims to ascertain how UAVs may be employed to elicit deceased transportation times, increased power efficiency, and improved safety. Resulting in optimized end point delivery. A combination of tools and techniques, involving a mathematical model, UAV simulations, redundant control systems, and custom designed electrical and mechanical components were used towards reaching the goal of a 10-kilogram maximum payload delivered 10 miles under 30 minutes. Two UAV prototypes were developed, the second of which (V2) showed promising results. Velocities achieved in V2, in combination with a versatile payload connector and proper networking, allowed for 5-10 mile deliveries of goods less than 8-kilograms to be achieved within a metropolis faster than the 30-minute benchmark

Airframe assembly, systems integration and flight testing of a long endurance electric UAV

The need to adopt new techniques and practices in the Aerospace Industry branch is a consequence of technological development. The present work aims to study the use of solar power as a main energy source in the aviation, in this case for a flight of long endurance of an unmanned air vehicle. This master thesis follows on previous works of the LEEUAV, where it was done the design and construction of a long endurance unmanned aerial system. Thus, the main objective of this work is the systems integration, flight testing and concepts validation. LEEUAV, a prototype of 4.5 meters’ wingspan and ultralight structure partially covered by solar cells was designed to fulfil a continuous flight mission of at least 8 hours on the equinox. The 5.42Kg remotely piloted aircraft was successfully tested showing the agreement with theoretical calculations already made. The longest flight achieved lasted more than 8.5 hours’ resulting in a total distance travelled of more than 75 km. In order to validate the airworthiness concept of the LEEUAV several flight tests were performed and their respective data (static and total pressure, air temperature, ground speed and pitch angle) was collected for further analysis, using a flight controller with multiple sensors on board. The results obtained allowed to study the general performance of the aircraft, the main defects, agreement with the theoretical results as well as determine the real values of aerodynamic coefficients (????, ????), through a reading and processing flight data algorithm in Software MATLAB. Finally, some future expectations for upcoming work are suggested in order to make the LEEUAV an Unmanned Aerial Vehicle of reference.A necessidade de adoção de novas técnicas e práticas no ramo da Indústria Aeronáutica é uma consequência do desenvolvimento tecnológico. O presente trabalho aborda o uso de energia solar como principal fonte de energia na aviação, com enfoque num voo de grande autonomia de uma aeronave não tripulada. Esta tese de mestrado surge na sequência de trabalhos anteriores relativos ao LEEUAV, nos quais se efetuou o projeto e construção de uma aeronave não tripulada de grande autonomia. Assim, o principal objetivo deste trabalho é a integração de sistemas, testes de voo e validação de conceitos. O UAV Solar LEEUAV é um protótipo de 4.5 metros de envergadura e de estrutura ultraleve parcialmente coberto de células fotovoltaicas sendo projetado para cumprir uma missão de voo contínuo de pelo menos 8h no equinócio. O avião de 5.42kg foi testado com sucesso mostrando a concordância com os cálculos teóricos já elaborados. O voo mais longo conseguido foi de 3.13 horas correspondendo a uma distância total percorrida de 96.265 km. De modo a validar o conceito de aeronavegabilidade do LEEUAV foram efetuados vários voos de teste e recolhidos dados de voo (pressão estática e dinâmica, temperatura do ar, velocidade no solo e ângulo de arfagem) para posterior análise, utilizando um controlador de voo com múltiplos sensores a bordo. A análise dos resultados obtidos permitiu precisar o desempenho geral da aeronave, os principais defeitos, concordância com os resultados teóricos assim como determinar os valores reais dos coeficientes aerodinâmicos (???? , ????) através de um algoritmo de leitura e processamento de dados de voo, em Software MATLAB. Por fim, são referidas algumas sugestões para o desenvolvimento de novos trabalhos com o objetivo de tornar O LEEUAV num veículo aéreo não tripulado de referência

Consortium for Robotics and Unmanned Systems Education and Research (CRUSER) 2019 Annual Report

Prepared for: Dr. Brian Bingham, CRUSER DirectorThe Naval Postgraduate School (NPS) Consortium for Robotics and Unmanned Systems Education and Research (CRUSER) provides a collaborative environment and community of interest for the advancement of unmanned systems (UxS) education and research endeavors across the Navy (USN), Marine Corps (USMC) and Department of Defense (DoD). CRUSER is a Secretary of the Navy (SECNAV) initiative to build an inclusive community of interest on the application of unmanned systems (UxS) in military and naval operations. This 2019 annual report summarizes CRUSER activities in its eighth year of operations and highlights future plans.Deputy Undersecretary of the Navy PPOIOffice of Naval Research (ONR)Approved for public release; distribution is unlimited

Consortium for Robotics and Unmanned Systems Education and Research (CRUSER) 2019 Annual Report

Prepared for: Dr. Brian Bingham, CRUSER DirectorThe Naval Postgraduate School (NPS) Consortium for Robotics and Unmanned Systems Education and Research (CRUSER) provides a collaborative environment and community of interest for the advancement of unmanned systems (UxS) education and research endeavors across the Navy (USN), Marine Corps (USMC) and Department of Defense (DoD). CRUSER is a Secretary of the Navy (SECNAV) initiative to build an inclusive community of interest on the application of unmanned systems (UxS) in military and naval operations. This 2019 annual report summarizes CRUSER activities in its eighth year of operations and highlights future plans.Deputy Undersecretary of the Navy PPOIOffice of Naval Research (ONR)Approved for public release; distribution is unlimited

A History of Materials and Technologies Development

The purpose of the book is to provide the students with the text that presents an introductory knowledge about the development of materials and technologies and includes the most commonly available information on human development. The idea of the publication has been generated referring to the materials taken from the organic and non-organic evolution of nature. The suggested texts might be found a purposeful tool for the University students proceeding with studying engineering due to the fact that all subjects in this particular field more or less have to cover the history and development of the studied object. It is expected that studying different materials and technologies will help the students with a better understanding of driving forces, positive and negative consequences of technological development, etc

Rediscovering the arcane science of ground handling large airships : an investigation into ways of reducing the risks inherent in the development of a new generation of very large airships and of establishing guidelines for their ground handling procedure

This research, which was begun as part of the now defunct CargoLifter project, concerns the ground handling and support systems of the large rigid airships (commonly known as "Zeppelins") that were built between 1900 and 1940. The intention was to assess the value of such historical information as has survived from the previous generation of very large airships in order to minimise the physical and financial risks inherent in the development of any future generations of such aircraft. The idea was to isolate and understand the fundamental issues that were actually encountered by the ground based personnel responsible for looking after the various British, German, American and Italian airships of the previous generation, and to gather as much information as possible about the techniques and operational procedures that were devised, tried and tested in the field. This information would then be used to establish guidelines for future projects that are based on real experience rather than on prediction, assumption or theory. Sadly, the CargoLifter project foundered in 2002; however the author had by then amassed sufficient research material for him to complete the study independently and to present it as a guide for the ground handling of hitherto unrealised concepts such as the proposed new "Transport category" or "CargoLifter" type large airships. Such practical skills as those required by airship ground crew personnel are normally passed on by firsthand instruction from one experienced practitioner to the trainee. This option is not available for the next generation of very large airships because there are no personnel alive today with any operational experience of the previous generation of really large airships. The problem therefore is to examine the historical records and to evaluate the written information in order to interpret it and pass on knowledge that will reduce the risk of future generations wasting their time in "re-inventing the wheel. " In the course of the study it was found that historical research (HR) enabled the results of the pre-war prototype projects to be usefully assessed despite the fact that very little of the material was written with that end in view. More specifically the analysis of historical airship activities (AHAA) revealed that it was possible to retrieve a considerable amount of lost or forgotten knowledge concerning the ground handling of very large airships, also to unearth ideas that were ahead of their time, which might be applicable today or in the future; and in addition to identify several areas worthy of further investigation (e. g. ideas that were rejected at the time but which may now be feasible due to technological progress). The research and analysis also uncovered some ideas and suggested solutions which are fundamentally flawed and that should be avoided by designers of large airships and their support systems. The work includes a detailed analysis of the tasks involved in the ground handling of very large airships and concludes with a suggested strategy for all those intent upon the design and planning of ground support infrastructures for any further large airship development projects either today or in the future

Desarrollo y validación de un modelo dinámico para una pila de combustible tipo PEM

JORNADAS DE AUTOMÁTICA (27) (27.2006.ALMERÍA)El objetivo de este trabajo es realizar un modelo dinámico detallado de una pila de combustible tipo PEM de 1.2 kW de potencia nominal. El modelo desarrollado incluye efectos como el ’flooding’ y la dinámica de la temperatura y es de utilidad para poder diseñar y ensayar controles tanto de la válvula de purga como de la refrigeración de la pila mediante un ventilador. Se ha desarrollado un novedoso tratamiento de la ecuación experimental que modela la curva de polarización que simplifica considerablemente su caracterización. Por último el modelo realizado ha sido validado con datos tomados de una pila real

Aeronautical engineering: A continuing bibliography with indexes (supplement 279)

This bibliography lists 759 reports, articles, and other documents introduced into the NASA scientific and technical information system in May 1992. Subject coverage includes: design, construction, and testing of aircraft and aircraft engines; aircraft components, equipment, and systems; ground support systems; and theoretical and applied aspects of aerodynamics and general fluid dynamics

Figures of Merit Remembrances of Those Who Built an Army-NASA Collaboration and a New Age of Rotary-Wing Technology 1965-1985

The authors of this book are the Figures of Meritthe scientists, engineers, technicians, secretaries, test pilots, managers, visionaries, and leaders who built a unique interagency collaboration under the Army-NASA Joint Agreement at Ames Research Center and ushered in a new age of rotary-wing technology. The U.S. Army Aeronautical Research Laboratory (AARL) was formed in 1965 to strengthen the Armys capabilities in aviation R&D, and the Army-NASA collaboration at Ames was intended to benefit both agencies by sharing personnel and facilities for research in areas of common interest in low-speed aviation