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Aquest ítem conté el treball original, defensat públicament amb data 19 d'octubre de 2021, així com una versió millorada del mateix a posteriori amb motiu de millora a petició del tribunal The design of BWB aircraft presents an alternative aircraft configuration with the characterization of being more sustainable, by reducing fuel consumption. However, its directional control is a new challenge that must be studied. In this context, the present TFG aims to study two configurations of rudder: one with a single central rudder of large dimensions, and another with two lateral rudders (on two tips of the BWB) of smaller dimensions. This study has been started from a design already created, by Dwivedi Y.D. and Jagadish D., of the central body and wings of the aircraft. Instead, the two rudder designs, the design with a single central rudder, and the design with two side rudders, located at the wing tips, have been developed from scratch, simply based on the existing rudders of the Boeing 737 MAX-9. The study has been done, first of all, using computational fluid dynamics (CFD) software, which is being key to the calculation of the behaviour of any fluid in contact with a solid, in this case an aircraft. Specifically, the Simscale web software has been used to calculate the aerodynamic forces exerted by each rudder configuration on our aircraft, in order to obtain the relationship between the different dimensionless coefficients (lift coefficient, aerodynamic drag coefficient, and yaw moment coefficient) and the rudder deflection angle. To fully study the performance of the aircraft, two types of simulation have been carried out: one where the aircraft is in the cruise phase and another in which it is in the takeoff phase, which differs in that the flow is compressible in the first case, and incompressible flow in the second. Secondly, the work has continued with an experimental wind tunnel study of the two BWB designs, which begins by printing the models with the EETAC 3D printer, models that have been previously generated with the SolidWorks CAD program. Later, aircraft models are introduced into the wind tunnel of the same EETAC, to obtain the experimental results on dimensionless coefficients and aerodynamic efficiency of each model. In the wind tunnel, 8 value shots were taken for each rudder, from 0º angle of attack (AoA) to end at 16º of AoA, in steps of 2º. Finally, thanks to the results obtained, it will be observed that the design with central rudder provides a slight improvement in aerodynamic efficiency, but, on the other hand, the design with side rudder is able to compensate for the moment due to engine failure. Objectius de Desenvolupament Sostenible::9 - Indústria, Innovació i Infraestructura

Trajectory Prediction (TP) is fundamental in Air Traffic Management (ATM). This research focuses on TP for the execution phase of the flight. In contrast to exploit black-box machine learning-based solutions, we tackle TP as an estimation problem, resorting to mathematical tools arising from statistical signal processing. Our first goal is to find an optimal and robust 4D (3D space plus time) TP solution, and the real-time estimation of the aircraft's active guidance mode, observing flight data collected from Automatic Dependent Surveillance-Broadcast (ADS-B), and transponder selective mode (Mode S) transmissions. Notice that this work is at a very early stage and only preliminary results are available.

This study aims to develop, train and evaluate a stability augmentation system for an airplane, in compilable code (C ++), using neural networks and the equations governing and airplane motion. The use of neural networks offers certain advantages in terms of learning capability, adaptability, fault tolerance and speed of response, which today are of great interest in the design of control systems.

The development of Flight Control Systems (FCS) coupled with the availability of other Commercial Off-The Shelf (COTS) components is enabling the introduction of Unmanned Aircraft Systems (UAS) into the civil market. UAS have great potential to be used in a wide variety of civil applications such as environmental applications, emergency situations, surveillance tasks and more. In general, they are specially well suited for the so-called D-cube operations (Dirty, Dull or Dangerous). Current technology greatly facilitates the construction of UAS. Sophisticated flight con- trol systems also make them accessible to end users with little aeronautical expertise. How- ever, we believe that for its successful introduction into the civil market, progress needs to be made to deliver systems able to perform a wide variety of missions with minimal reconfiguration and with reduced operational costs. Most current flight plan specification mechanisms consist in a simple list of waypoints, an approach that has important limitations. This paper proposes a new specification mech- anism with semantically richer constructs that will enable the end user to specify more complex flight plans. The proposed formalism provides means for specifying iterative be- havior, conditional branching and other constructs to dynamically adapt the flight path to mission circumstances. Collaborating with the FCS, a new module on-board the UAS will be in charge of executing these plans. This research also studies how the proposed flight plan structure can be tailored to the specific needs of remote sensing. For these type of applications well structured and efficient area and perimeter scanning is mandatory. In this paper we introduce several strategies focused to optimize the scanning process for tactical or mini UAS. The paper also presents a prototype implementation of this module and the results obtained in simulations.

The generalized development of UAS complex applications are still limited by the absence of systems that support the implementation of the actual mission. UAS design faces the development of specific systems to control their desired flight-profile, sensor activation/configuration along the flight, data storage and eventually its transmission to the ground control. All this elements may delay and increase the risk and cost of the project. This paper introduces a flexible and reusable hardware/software architecture designed to facilitate the development of UAS-based complex applications. This flexibility is organized into a user-parameterizable UAS service abstraction layer (USAL). The USAL defines a collection of standard services are their interrelations as a basic starting point for further development by users. Functionalities like enhanced flight-plans, a mission control engine, data storage, communications management, etc. are offered. Additional services can be included according to requirements but all existing services and inter-service communication infrastructure can be exploited and tailored to specific needs. This approach reduces development times and risks, but at the same time gives the user higher levels of flexibility and permits the development of more ambitious applications.

Unmanned Aerial Systems (UAS) are slowing becoming e cient platforms that can be applied in scienti c/commercial remote sensing applications. UAS may o er interesting bene ts in terms of cost, exibility, endurance, etc. On the other side, the complexity of developing a full UAS-system is currently limiting its practical application. Currently, only large organizations like NASA or NOAA have enough budget and infrastructure to develop such applications. Nowadays, UAS technology o ers feasible technical solutions for airframes, ight control, communications, and a wide set of multi-spectrum sensors. However, the generalized development of remote sensing applications are still limited by the absence of systems that support the development of the actual UAS sensing mission. This paper introduces a exible and reusable hardware/software architecture designed to facilitate the development of UAS-based remote sensing applications. This exibility is organized into an user-parameterizable UAS Service Abstraction Layer (USAL). The USAL de nes a collection of standard services are their interrelations as a basic starting point for further development by users. Functionalities like enhanced ight-plans, a mission control engine, data storage, communications management, etc. are o ered. Additional services can be included according to requirements but all existing services and inter-service communication infrastructure can be exploited and tailored to speci c needs. The overall USAL architecture is demonstrated by means of a wild land re remote sensing application currently being developed to support re ghters in the Mediterranean area.

Unmanned Aircraft Systems (UAS) are increasing their communication subsystems complexity as they are using several data links both for redundancy and for tacking with different communication requirements: different ranges, bandwidth, power consumption or cost. Inside the airframe a similar tendency with respect to communications is appearing. Modern digital avionics are mainly implemented as distributed computing architectures. This work describes Marea, a middleware specifically designed to fulfill UAS communications and their application to the design of complex distributed UAS avionics.

Unmanned Aerial System (UAS) are becoming viable aerial platforms for civil oriented monitoring applications. However, in most cases the selected UAS platforms are ad-hoc vehicles which include highly heterogeneous avionics. Avionics on-board may be COSTS modules that have highly different non-standard power requirements. Additionally, the available power sources in these UAS may be fairly limited or even restricted to battery units. This paper introduces the ELectrical Manager Service (ELMS), an on-board system in charge of offering a flexible power supply architecture that supports minimal reconfiguration overhead for a wide variety of UAS missions. The ELMS Service is designed to offer a continuous monitoring of the state of the power network, and a coherent and controlled response in front of power supply contingencies. The ELMS will monitor the batteries and generator status, the power consumption of the avionics and other systems, manage the connection/disconnections of systems, and provide power availability estimations. The ELMS Service is part of an architecture designed to facilitate the execution of UAS civil missions, the USAL. The USAL is built as a set of cooperating services in a purely distributed and scalable architecture with a middleware that manages inter-service communications.

This paper presents an embedded hardware/software architecture specially designed to be applied on mini/micro Unmanned Aerial Vehicles (UAV). An UAV is low-cost non-piloted airplane designed to operate in D-cube (Dangerous-Dirty-Dull) situations [8]. Many types of UAVs exist today; however with the advent of UAV's civil applications, the class of mini/micro UAVs is emerging as a valid option in a commercial scenario. This type of UAV shares limitations with most computer embedded systems: limited space, limited power resources, increasing computation requirements, complexity of the applications, time to market requirements, etc. UAVs are automatically piloted by an embedded system named “Flight Control System”. Many of those systems are commercially available today, however no commercial system exists nowadays that provides support to the actual mission that the UAV should perform. This paper introduces a hardware/software architecture specially designed to operate as a flexible payload and mission controller in a mini/micro UAV. Given that the missions UAVs can carry on justify their existence, we believe that specific payload and mission controller s for UAV should be developed. Our architectonic proposal for them orbits around four key elements: a LAN based distributed and scalable hardware architecture, a service/subscription based software architecture and an abstraction communication layer.

Unmanned Aircraft Systems may allow to y an uninhabited airplane or satellite with an autonomous control and monitored by the supervisor on ground. Safety y must be guarantee as the rest of airworthiness airplanes or space compliance satellites. The Unmanned Aircraft Systems were designed to operate in dangerous situations, like military missions bud nowadays, civil commercial applications come to be feasible due to the evolution in distributed embedded avionics systems. Dull and tedious surveillance applications are desired for this Unmanned Aerial Vehicles. A pico-satellite is a less than a kilogram mass satellite used mainly on educational projects for Low Earth Orbit (LEO) missions. Due to short time of live, down-link communications are implemented in a very high level of integration and non-gravity conditions in order to deliberate the scienti c information before drop down to the atmosphere. Both, Unmanned Aerial Vehicles and pico-satellites present same electromagnetic compatibility problems. This high level of integration, some times brings an electromagnetic interference situation between embedded systems especially because the near eld of emissions are present in the Unmanned Aircraft System reduced con ned avionics bay. Emission, Susceptibility, and Path are playing in this environment. That was our experience with an UAV Megastar model. The near earth antenna re ection produced a multi-path coupling. The radio transmitter antenna makes unserviceable the entire ight control surfaces, situation that makes an unsafe y. Also, during the pico-satellite design we must take in consideration the near eld for a good electromagnetic compatibility requirements. This paper is an electromagnetic compatibility study for Unmanned Aircraft System. We will show a case of real electromagnetic interference in our particular UAV Megastar, and how was solved. We will present some good EMC practices in order to translate the distributed embedded avionics platform to our new UAV Shadow MK1. Also we present our pico-satellite design and many examples of solutions of electromagnetic interferences. Finally we will consider an electromagnetic interference reduction check list applied on Unmanned Aircraft System where avionics bay con guration may change depending on the requirements of the mission.

This paper introduces a simulation architecture to evaluate the implementation of a va- riety of civil UAS missions with little recon guration time and overhead. This architecture, called Icarus Simulation Integrated Scenario (ISIS), is capable of simulating the behavior of the UAS from the mission point of view, but also is able to include additional aerial/ground vehicles. Additionally, the mutual interaction between vehicles and the interaction with their surrounding environment is modeled. The objective of ISIS is to minimize both the development e ort and risk, as well as to provide a feasible migration of the software from the testbed platform to the real ight platform. The UAS simulator is designed as a distributed simulation architecture in which vehicles and environment are modeled through specialized pieces of software. A service-oriented communication middleware provides the underlying infrastructure to easily implement the inter-vehicle coordination and even the coordination with third party applications providing additional simulated vehicles or simulated environment. A UAS-based forest re monitor- ing application is selected to describe the ISIS capabilities to coordinate the simulation of a multi-vehicle cooperative environment developing a complex mission.

This paper addresses various aspects of the design and development of the pilot interface for the exploitation of highly advanced flight plan capabilities specifically designed for Unmanned Aerial Systems (UAS). This flight plan capabilities are built on top a flexible and reusable hardware/software architecture designed to facilitate the development of UAS-based applications. This flexibility is organized into an user-parameterizable UAS Service Abstraction Layer (USAL). The USAL defines a collection of standard services are their interrelations as a basic starting point for further development by UAS users. Previous research presented the advanced flying capabilities of a UAS as an extension of the Flight Control System (FCS) functionalities. Assuming a UAS with a FCS that ensures safe and stable maneuvers, we complement it with a highly capable flight plan management system. USAL flight plan is characterized by offering semantically much richer constructs than those present in most current UAS autopilots, which rely on simple lists of waypoints. This list of waypoints approach has several important limitations: it is difficult to specify complex trajectories and it does not support constructs such as conditional forks or iterations, small changes may imply having to deal with a considerable amount of waypoints and it provides no mechanism for adapting to mission time circumstances. To address these issues a new flight plan specification mechanism is proposed, that incorporates a leg concept extended to accommodate higher level constructs for specifying iterations and forks. Additional leg types, referred to as parametric leg, are also introduced. The trajectory defined by a parametric leg is automatically generated as a function of mission variables, enabling dynamic behavior and providing a very valuable means for adapting the flight to the mission evolution. Another level of adaption is provided by the conditions governing the decision-making in intersection le- - gs and the finalization of iterative legs. In this work we will focus on the development of the pilot interface for the exploitation of the introduced flight plan capabilities. The interface design requirements address an increase level of automated operation and support to react to unexpected requirements due to mission changes. Therefore, this interaction includes the available mechanisms to update the flight-plan according to UAS mission requirements, skip parts of it, react to operational contingencies, etc.