817 resultados para AVIATION
Design and Development of a Research Framework for Prototyping Control Tower Augmented Reality Tools
Resumo:
The purpose of the air traffic management system is to ensure the safe and efficient flow of air traffic. Therefore, while augmenting efficiency, throughput and capacity in airport operations, attention has rightly been placed on doing it in a safe manner. In the control tower, many advances in operational safety have come in the form of visualization tools for tower controllers. However, there is a paradox in developing such systems to increase controllers' situational awareness: by creating additional computer displays, the controller's vision is pulled away from the outside view and the time spent looking down at the monitors is increased. This reduces their situational awareness by forcing them to mentally and physically switch between the head-down equipment and the outside view. This research is based on the idea that augmented reality may be able to address this issue. The augmented reality concept has become increasingly popular over the past decade and is being proficiently used in many fields, such as entertainment, cultural heritage, aviation, military & defense. This know-how could be transferred to air traffic control with a relatively low effort and substantial benefits for controllers’ situation awareness. Research on this topic is consistent with SESAR objectives of increasing air traffic controllers’ situation awareness and enable up to 10 % of additional flights at congested airports while still increasing safety and efficiency. During the Ph.D., a research framework for prototyping augmented reality tools was set up. This framework consists of methodological tools for designing the augmented reality overlays, as well as of hardware and software equipment to test them. Several overlays have been designed and implemented in a simulated tower environment, which is a virtual reconstruction of Bologna airport control tower. The positive impact of such tools was preliminary assessed by means of the proposed methodology.
Resumo:
The innovation in several industrial sectors has been recently characterized by the need for reducing the operative temperature either for economic or environmental related aspects. Promising technological solutions require the acquisition of fundamental-based knowledge to produce safe and robust systems. In this sense, reactive systems often represent the bottleneck. For these reasons, this work was focused on the integration of chemical (i.e., detailed kinetic mechanism) and physical (i.e., computational fluid dynamics) models. A theoretical-based kinetic mechanism mimicking the behaviour of oxygenated fuels and their intermediates under oxidative conditions in a wide range of temperature and pressure was developed. Its validity was tested against experimental data collected in this work by using the heat flux burner, as well as measurements retrieved from the current literature. Besides, estimations deriving from existing models considered as the benchmark in the combustion field were compared with the newly generated mechanism. The latter was found to be the most accurate for the investigated conditions and fuels. Most influential species and reactions on the combustion of butyl acetate were identified. The corresponding thermodynamic parameter and rate coefficients were quantified through ab initio calculations. A reduced detailed kinetic mechanism was produced and implemented in an open-source computational fluid dynamics model to characterize pool fires caused by the accidental release of aviation fuel and liquefied natural gas, at first. Eventually, partial oxidation processes involving light alkenes were optimized following the quick, fair, and smoot (QFS) paradigm. The proposed procedure represents a comprehensive and multidisciplinary approach for the construction and validation of accurate models, allowing for the characterization of developing industrial sectors and techniques.
Resumo:
The advances in the aviation field, particularly the development of electric flying vehicles, as UAV and eVTOL, paved the way for setting Urban Air Mobility (UAM) services. UAM would provide services for passengers, goods and emergencies and could offer faster trips than ground ones. It is expected that early UAM operations will be performed at Very Low-Level airspace as 0-500 m Above Ground Level. The purpose of this research is to both explore the main features of UAM and test an aerial network model, which could be integrated in a multimodal transport system where ground and aerial mobility services are provided. Analyses on UAM transport system involved two sub-systems: the transport demand sub-system, i.e., the mobility requirements, and the transport supply sub-system, i.e., the service and facilities enabling mobility. At first, the UAM demand levels and features for an Airport Shuttle service have been explored through a suitable survey, by combining Revealed and Stated Preference methodologies, and by calibrating some discrete mode choice models. Then, the focus has been on the transport supply model for UAM services, by focusing on both the ground access points (vertiports) and the aerial network model. A suitable three-dimensional urban aerial network (3D-UAN) model that could support fast aerial connections between O/D pairs has been proposed. Some tests have been implemented to verify the feasibility of the proposed model. Some flying vehicles supporting an Airport Shuttle service have been simulated on the aerial network, which has been specified in terms of both topological features and link transport costs. The preliminary results have showed that the proposed 3D-UAN model could be suitable for supporting UAM services. As for transport engineering, the UAM system framework proposed in this thesis paves the way for further research on air-ground multimodality in urban areas.
Resumo:
Gaze estimation has gained interest in recent years for being an important cue to obtain information about the internal cognitive state of humans. Regardless of whether it is the 3D gaze vector or the point of gaze (PoG), gaze estimation has been applied in various fields, such as: human robot interaction, augmented reality, medicine, aviation and automotive. In the latter field, as part of Advanced Driver-Assistance Systems (ADAS), it allows the development of cutting-edge systems capable of mitigating road accidents by monitoring driver distraction. Gaze estimation can be also used to enhance the driving experience, for instance, autonomous driving. It also can improve comfort with augmented reality components capable of being commanded by the driver's eyes. Although, several high-performance real-time inference works already exist, just a few are capable of working with only a RGB camera on computationally constrained devices, such as a microcontroller. This work aims to develop a low-cost, efficient and high-performance embedded system capable of estimating the driver's gaze using deep learning and a RGB camera. The proposed system has achieved near-SOTA performances with about 90% less memory footprint. The capabilities to generalize in unseen environments have been evaluated through a live demonstration, where high performance and near real-time inference were obtained using a webcam and a Raspberry Pi4.
Resumo:
Studio dei metodi di progettazione per lo sviluppo di eliche aeronautiche. Come caso di studio è stata scelta la progettazione di un’elica che ottimizzi le prestazioni del Risen, prodotto dalla Porto Aviation Group. Questo ultraleggero monta motore Rotax915IS, che eroga una potenza considerevolmente maggiore rispetto ai motori adottati in precedenza: sono state, quindi, progettate una serie di eliche in grado di convertire in maniera efficiente la coppia ricevuta in spinta nelle diverse fasi di volo del velivolo. E' incluso nella tesi uno studio di sensitività in cui è stato verificato come varia la spinta in funzione dei diversi parametri costruttivi dell'elica aeronautica. Lo sviluppo dell’elica avviene attraverso il seguente percorso: 1) definizione parametri di volo e funzionamento motore del velivolo a cui accoppiare l'elica, 2) studio delle prestazioni dell'aereo con le eliche già disponibili così da potere validare i calcoli, 3) stima delle prestazioni dell'aereo in seguito a variazioni delle caratteristiche geometriche della pala; 4) sintesi caratteristiche costruttive per ottenere una pala in grado di fornire prestazioni soddisfacenti in ogni fase del volo. Gli studi sono stati supportati da analisi su codici software commerciali, al fine di valutare l’influenza dei parametri costruttivi sulle prestazioni del velivolo a cui viene accoppiata l'elica. Lo studio ha condotto allo sviluppo di cinque pale, una delle quali presenta ottime prestazioni.
Resumo:
Additive Manufacturing (AM), also known as “3D printing”, is a recent production technique that allows the creation of three-dimensional elements by depositing multiple layers of material. This technology is widely used in various industrial sectors, such as automotive, aerospace and aviation. With AM, it is possible to produce particularly complex elements for which traditional techniques cannot be used. These technologies are not yet widespread in the civil engineering sector, which is slowly changing thanks to the advantages of AM, such as the possibility of realizing elements without geometric restrictions, with less material usage and a higher efficiency, in particular employing Wire-and-Arc Additive Manufacturing (WAAM) technology. Buildings that benefit most from AM are all those structures designed using form-finding and free-form techniques. These include gridshells, where joints are the most critical and difficult elements to design, as the overall behaviour of the structure depends on them. It must also be considered that, during the design, the engineer must try to minimize the structure's own weight. Self-weight reductions can be achieved by Topological Optimization (TO) of the joint itself, which generates complex geometries that could not be made using traditional techniques. To sum up, weight reductions through TO combined with AM allow for several potential benefits, including economic ones. In this thesis, the roof of the British Museum is considered as a case study, analysing the gridshell structure of which a joint will be chosen to be designed and manufactured, using TO and WAAM techniques. Then, the designed joint will be studied in order to understand its structural behaviour in terms of stiffness and strength. Finally, a printing test will be performed to assess the production feasibility using WAAM technology. The computational design and fabrication stages were carried out at Technische Universität Braunschweig in Germany.
Resumo:
Il presente lavoro di tesi si pone come obiettivo l’individuazione di modelli matematici che possano essere utilizzati per la configurazione di simulatori di volo aerei elettrici dell’aviazione generale. In particolare, sono state trovate in letteratura delle formule da utlizzare per modellare eliche, motori elettrici di varie tipologie e batterie. Per meglio comprendere l’impatto dell’adozione dei motori elettrici sui velivoli dell’aviazione generale sono stati effettuati dei confronti di dati, in cui si è preso come riferimento il motore a combustione interna Continental O-300 montato sui Cessna C172. Successivamente, sono stati implementati i modelli dinamici in Simulink di motori elettrici che potrebbero sostituire il motore a combustione interna sopra citato. Sono, poi, state eseguite alcune comparazioni tra i risultati ottenuti in termini di spinte ottenibili, potenze e autonomie, e numero di giri di rotazione dell’elica per diversi motori elettrici. Per effettuare le simulazioni è stato utilizzato il software Simulink: ambiente in cui sono stati sviluppati modelli dinamici di propulsione sia tradizionale che elettrica. Nella parte conclusiva della tesi, sono riportate alcune considerazioni volte a stimare l'autonomia di un velivolo simile al Cessna C172, in cui si sotituisce il motore a combustione interna con un motore elettrico a parità di peso massimo al decollo e l’andamento di quest'ultimo in funzione dell’autonomia per un velivolo elettrico. I risultati ottenuti da queste ultime simulazioni suggeriscono che la conversione ad elettrico è attualmente critica in quanto la ridotta densità di energia delle batterie porta ad un significativo decadimento dell'autonomia generale.