18 research outputs found
Avion 2007-03-27
https://commons.erau.edu/avion/2076/thumbnail.jp
An Ontological Approach to Autonomous Navigational Decision Making in Aircraft Systems
Aircraft systems are becoming increasingly complex, and automation increasingly necessary for safe aircraft operation. Current industry trends are encouraging either a reduction of crew num- bers or complete elimination. After surveying the evolution of aircraft automation systems, pilot tasks and situational awareness, we argue that a hurdle to crew reduction is that of autonomous navigation. In this thesis, we put forth an ontology based approach for defining autonomous navigational decision making. The ontology is designed to capture elements representing the environment in which aircraft operate; the “air environment”. An expert system is then pro- grammed and uses the ontology as its knowledge base. Combining the environmental ontology with a second one describing a generic air vehicle, the expert system is programmed to make navigational decisions based on environment, vehicle state and mission. Case studies show the functionality of the implementation, and a validation study demonstrates the feasibility of the solution. The thesis closes by relating it to other research and recently released industry avionics solutions
Autonomous landing of fixed-wing aircraft on mobile platforms
E
n esta tesis se propone un nuevo sistema que permite la operación de aeronaves
autónomas sin tren de aterrizaje. El trabajo está motivado por el interés industrial
en aeronaves con la capacidad de volar a gran altitud, con más capacidad de carga útil y
capaces de aterrizar con viento cruzado.
El enfoque seguido en este trabajo consiste en eliminar el sistema de aterrizaje de una
aeronave de ala fija empleando una plataforma móvil de aterrizaje en tierra. La aeronave y
la plataforma deben sincronizar su movimiento antes del aterrizaje, lo que se logra mediante
la estimación del estado relativo entre ambas y el control cooperativo del movimiento.
El objetivo principal de esta Tesis es el desarrollo de una solución práctica para el
aterrizaje autónomo de una aeronave de ala fija en una plataforma móvil. En la tesis se
combinan nuevos métodos con experimentos prácticos para los cuales se ha desarrollado
un sistema de pruebas específico.
Se desarrollan dos variantes diferentes del sistema de aterrizaje. El primero presta atención especial a la seguridad, es robusto ante retrasos en la comunicación entre vehículos y
cumple procedimientos habituales de aterrizaje, al tiempo que reduce la complejidad del
sistema. En el segundo se utilizan trayectorias optimizadas del vehículo y sincronización
bilateral de posición para maximizar el rendimiento del aterrizaje en términos de requerimientos de longitud necesaria de pista, pero la estabilidad es dependiente del retraso de
tiempo, con lo cual es necesario desarrollar un controlador estabilizador ampliado, basado
en pasividad, que permite resolver este problema.
Ambas estrategias imponen requisitos funcionales a los controladores de cada uno de
los vehículos, lo que implica la capacidad de controlar el movimiento longitudinal sin
afectar el control lateral o vertical, y viceversa. El control de vuelo basado en energía se
utiliza para proporcionar dicha funcionalidad a la aeronave.
Los sistemas de aterrizaje desarrollados se han analizado en simulación estableciéndose los límites de rendimiento mediante múltiples repeticiones aleatorias. Se llegó a
la conclusión de que el controlador basado en seguridad proporciona un rendimiento de
aterrizaje satisfactorio al tiempo que suministra una mayor seguridad operativa y un menor
esfuerzo de implementación y certificación. El controlador basado en el rendimiento es
prometedor para aplicaciones con una longitud de pista limitada. Se descubrió que los beneficios del controlador basado en el rendimiento son menos pronunciados para una
dinámica de vehículos terrestres más lenta.
Teniendo en cuenta la dinámica lenta de la configuración del demostrador, se eligió el
enfoque basado en la seguridad para los primeros experimentos de aterrizaje. El sistema
de aterrizaje se validó en diversas pruebas de aterrizaje exitosas, que, a juicio del autor,
son las primeras en el mundo realizadas con aeronaves reales. En última instancia, el
concepto propuesto ofrece importantes beneficios y constituye una estrategia prometedora
para futuras soluciones de aterrizaje de aeronaves.In this thesis a new landing system is proposed, which allows for the operation of
autonomous aircraft without landing gear. The work was motivated by the industrial
need for more capable high altitude aircraft systems, which typically suffer from low
payload capacity and high crosswind landing sensitivity. The approach followed in this
work consists in removing the landing gear system from the aircraft and introducing a
mobile ground-based landing platform. The vehicles must synchronize their motion prior
to landing, which is achieved through relative state estimation and cooperative motion
control. The development of a practical solution for the autonomous landing of an aircraft
on a moving platform thus constitutes the main goal of this thesis. Therefore, theoretical
investigations are combined with real experiments for which a special setup is developed
and implemented.
Two different landing system variants are developed — the safety-based landing system is
robust to inter-vehicle communication delays and adheres to established landing procedures,
while reducing system complexity. The performance-based landing system uses optimized
vehicle trajectories and bilateral position synchronization to maximize landing performance
in terms of used runway, but suffers from time delay-dependent stability. An extended
passivity-based stabilizing controller was implemented to cope with this issue. Both
strategies impose functional requirements on the individual vehicle controllers, which
imply independent controllability of the translational degrees of freedom. Energy-based
flight control is utilized to provide such functionality for the aircraft.
The developed landing systems are analyzed in simulation and performance bounds are
determined by means of repeated random sampling. The safety-based controller was found
to provide satisfactory landing performance while providing higher operational safety,
and lower implementation and certification effort. The performance-based controller
is promising for applications with limited runway length. The performance benefits
were found to be less pronounced for slower ground vehicle dynamics. Given the slow
dynamics of the demonstrator setup, the safety-based approach was chosen for first landing
experiments. The landing system was validated in a number of successful landing trials,
which to the author’s best knowledge was the first time such technology was demonstrated on the given scale, worldwide. Ultimately, the proposed concept offers decisive benefits
and constitutes a promising strategy for future aircraft landing solutions
Standardization Roadmap for Unmanned Aircraft Systems, Version 1.0
This Standardization Roadmap for Unmanned Aircraft Systems, Version 1.0 (“roadmap”) represents the culmination of the UASSC’s work to identify existing standards and standards in development, assess gaps, and make recommendations for priority areas where there is a perceived need for additional standardization and/or pre-standardization R&D.
The roadmap has examined 64 issue areas, identified a total of 60 gaps and corresponding recommendations across the topical areas of airworthiness; flight operations (both general concerns and application-specific ones including critical infrastructure inspections, commercial services, and public safety operations); and personnel training, qualifications, and certification. Of that total, 40 gaps/recommendations have been identified as high priority, 17 as medium priority, and 3 as low priority. A “gap” means no published standard or specification exists that covers the particular issue in question. In 36 cases, additional R&D is needed.
The hope is that the roadmap will be broadly adopted by the standards community and that it will facilitate a more coherent and coordinated approach to the future development of standards for UAS. To that end, it is envisioned that the roadmap will be widely promoted and discussed over the course of the coming year, to assess progress on its implementation and to identify emerging issues that require further elaboration
Pilot\u27s Handbook of Aeronautical Knowledge, 2016
The Pilot’s Handbook of Aeronautical Knowledge provides basic knowledge that is essential for pilots. This handbook introduces pilots to the broad spectrum of knowledge that will be needed as they progress in their pilot training. Except for the Code of Federal Regulations pertinent to civil aviation, most of the knowledge areas applicable to pilot certification are presented.
The Pilot’s Handbook of Aeronautical Knowledge provides basic knowledge for the student pilot learning to fly, as well as pilots seeking advanced pilot certification. For detailed information on a variety of specialized flight topics, see specific Federal Aviation Administration (FAA) handbooks and Advisory Circulars (ACs).
Occasionally the word “must” or similar language is used where the desired action is deemed critical. The use of such language is not intended to add to, interpret, or relieve a duty imposed by Title 14 of the Code of Federal Regulations (14 CFR).
It is essential for persons using this handbook to become familiar with and apply the pertinent parts of 14 CFR and the Aeronautical Information Manual (AIM). The AIM is available online at www.faa.gov. The current Flight Standards Service airman training and testing material and learning statements for all airman certificates and ratings can be obtained from https://www.faa.gov
Standardization Roadmap for Unmanned Aircraft Systems, Version 2.0
This Standardization Roadmap for Unmanned Aircraft Systems, Version 2.0 (“roadmap”) is an update to version 1.0 of this document published in December 2018. It identifies existing standards and standards in development, assesses gaps, and makes recommendations for priority areas where there is a perceived need for additional standardization and/or pre-standardization R&D.
The roadmap has examined 78 issue areas, identified a total of 71 open gaps and corresponding recommendations across the topical areas of airworthiness; flight operations (both general concerns and application-specific ones including critical infrastructure inspections, commercial services, and public safety operations); and personnel training, qualifications, and certification. Of that total, 47 gaps/recommendations have been identified as high priority, 21 as medium priority, and 3 as low priority. A “gap” means no published standard or specification exists that covers the particular issue in question. In 53 cases, additional R&D is needed.
As with the earlier version of this document, the hope is that the roadmap will be broadly adopted by the standards community and that it will facilitate a more coherent and coordinated approach to the future development of standards for UAS. To that end, it is envisioned that the roadmap will continue to be promoted in the coming year. It is also envisioned that a mechanism may be established to assess progress on its implementation
Mind wandering dynamic in automated environments and its influence on out-of-the-loop situations
Des niveaux d'automatisation élevés sont intégrés dans les environnements critiques pour satisfaire la demande croissante de systèmes plus sûrs. Cette philosophie déplace les opérateurs vers un rôle de supervision et crée de nouveaux problèmes appelés problèmes de performance liés à la sortie de boucle (SDB). L'émergence de pensées sans lien avec ici et maintenant, ou divagation attentionnelle (DA), pourrait affecter les opérateurs dans des situations de SDB par le biais du découplage perceptuel induit. Cette thèse a étudié la dynamique de la DA dans les situations de SDB et son influence sur les opérateurs. Nous avons en premier lieu examiné les preuves dans la littérature pointant vers un lien entre le problème de performance lié à la SDB et la DA. Nous avons complété cette analyse théorique en rapportant la tendance des pilotes (collectée avec un questionnaire) à
rencontrer plus de problèmes avec leur pilote automatique pour ceux ayant une plus grande propension au MW non lié à la tâche. Nous avons ensuite mené trois expériences dans des
conditions de SDB. Nous avons observé une augmentation significative des épisodes de DA dans les situations de SDB quelle que soit la fiabilité du système, par rapport aux
conditions manuelles. Les épisodes de DA étaient également accompagnés d'un découplage perceptuel vis-à-vis de la tâche créé par la DA non lié à la tâche. Ce découplage était
visible sur des rapports de demande mentale ainsi que les signaux oculométriques et encéphalographiques. Dans l'ensemble, nos résultats démontrent la possibilité d'utiliser des marqueurs physiologiques de la DA dans des environnements de SDB complexes. Nous discutons de nouvelles perspectives d'utilisation des marqueurs de la DA pour caractériser les problèmes de performance liés à la SDB. Sans vouloir arrêter aveuglément l'émergence de la DA, qui pourrait être bénéfique pour les opérateurs, les recherches futures devraient se concentrer sur la conception de systèmes capables de gérer la DA et d'identifier les informations nécessaires pour faciliter la rentrée de l'opérateur dans la boucle de contrôle.Higher levels of automation are progressively integrated in critical environments to satisfy the increasing demand for safer systems. Such philosophy moves operators to a
supervisory role, also called out-of-the-loop (OOTL) situations. Unfortunately, OOTL situations also create a new kind of human-machine interaction issues, called OOTL
performance problem. The dramatic consequences of OOTL performance problem stress the need to identify which mechanisms could influence their appearance. The emergence of thoughts unrelated to the here and now, labeled mind wandering (MW), could affect operators in OOTL situations through the perceptual decoupling induced. This thesis
investigates MW dynamic in OOTL situations and its influence on operators. We firstly reviewed the evidences in the literature underlining a link between OOTL performance
problem and MW. We completed theoretical insights by reporting pilots' tendency (collected with a questionnaire) to encounter more problems with autopilots when experiencing
more task-unrelated MW. Then, we conducted three experiments in OOTL conditions using an obstacle avoidance task. With non-expert population and sessions longer than 45 minutes,
we observed a significant increase of MW in OOTL situations compared to manual conditions, independently of system reliability. MW episodes were also accompanied by a perceptual decoupling from the task induced by task-unrelated MW. This decoupling was visible on reports of mental demand as well as oculometric (pupil size, blinks) and encephalographic (N1 component, alpha activity) signals. Overall, our results demonstrate the possibility to use physiological markers of MW in complex OOTL environments. We discuss new perspectives towards the use of MW markers to characterize the OOTL performance problem. Instead of blindly stopping MW episodes, which could have benefits for operators, future research should focus on designing systems able to cope with MW and identify information needed to facilitate the reentry in the control loop when needed