Actuator saturation is a well studied subject regarding control theory. However, little research exist regarding aircraft behavior during actuator saturation. This paper aims to identify flight mechanical parameters that can be useful when analyzing actuator saturation. The studied aircraft is an unstable delta-canard aircraft. By varying the aircraft’s center-of-gravity and applying a square wave input in pitch, saturated actuators have been found and investigated closer using moment coeÿcients as well as other flight mechanical parameters. The studied flight mechanical parameters has proven to be highly relevant when analyzing actuator saturation, and a simple connection between saturated actuators and moment coeÿcients has been found. One can for example look for sudden changes in the moment coeÿcients during saturated actuators in order to find potentially dangerous flight cases. In addition, the studied parameters can be used for robustness analysis, but needs to be further investigated. Lastly, the studied pitch square wave input shows no risk of aircraft departure with saturated elevons during flight, provided non-saturated canards, and that the free-stream velocity is high enough to be flyable. / Styrdonsmättning är ett välstuderat ämne inom kontrollteorin. Däremot existerar det lite forskning gällande flygplansbeteende vid styrdonsmättning. Syftet med den här rap-porten är att identifiera flygmekaniska parametrar som kan vara användbara vid analys av styrdonsmättning av ett instabilt delta-canard flygplan. Genom att variera flygplan-ets tyngdpunkt och applicera en pulsinmatning i tippled har styrdonsmättning hittats och undersökts närmare med momentkoeÿcienter, men även med andra flygmekaniska parametrar. De studerade parametrarna har visat sig vara mycket relevanta vid analys av styrdonsmättning och ett enkelt samband mellan mättade styrdon och momentcoeÿcienter har hittats. Det går till exempel att leta efter plötsliga ändringar i momentkoeÿcienterna under mättning av styrdon för att hitta potentiellt farliga flygsituationer. De studerade parametrarna kan användas i en robusthetsanalys, men vidare forskning krävs. Den studerade pulsinmatningen i tippled visar även att så länge canarderna inte ligger i mät-tning, trots att elevonerna ligger i mättning, så är det ingen fara att flyga, förutsatt att flyghastigheten är tillräckligt hög.

Flight data are recorded on every commercial aircraft to be analysed and therefore improve flight safety. This analysis is done through various algorithms computing new parameters and detecting precise instants of the flight (rotation, take-off, touchdown, etc.). These instants are used to flag events when a safety risk occurred during the flight. High-accuracy in the detection of instants is of prime importance to avoid missed events and flagged false events. / Flygdata registreras på alla kommersiella flygplan för att analyseras och därmed förbättra flygsäkerheten. Denna analys görs genom olika algoritmer som beräknar nya parametrar och upptäcker exakta tillfällen av flygningen (rotation, start, landning, etc.). Dessa tillfällen används för att flagga händelser då en säkerhetsrisk uppstått under flygningen. Hög noggrannhet i upptäckten av dessa tillfällen är av största betydelse för att undvika missade händelser och flaggade falska händelser.

Flight-testing represents an important step of an airplane development. Every new or modified aircraft configuration is tested. Through set of tests, the quality and reliability of aircrafts are guaranteed. At Dassault Aviation, the flight test Directorate responsible for carrying out flight tests is located at Istres, in South of France. One major test before flying is the Ground Vibration Test (GVT). The aim of this test is to measure Eigen frequencies and mode shapes of the structure. Those results are after compared to the ones given by the finite element model in order to verify it or update it. Determining the structural behavior has a significant importance for aircraft safety, for instance, it helps to determine the aircraft’s flutter boundary. Under unsteady aerodynamic loads, the aircraft structure can be dynamically unstable, meaning that the amplitude of oscillations increases with time. This phenomenon called flutter can highly damage the airplane or can even lead to the complete destruction of its structure. GVTs are performed by exciting the aircraft with oscillatory forces on designated parts. Then, hundreds of accelerometers are used to measure the vibrations. Knowing exactly the input excitation and how the structure answers, it is possible to calculate the relations (so-called transfer functions) between the applied oscillatory forces and the acceleration measurements. This measurement method based on accelerometers is highly accurate; however, one accelerometer only provides one punctual measurement. In order to have an infinite number of measurement points and thus, a better understanding of the mode shapes, new measurement methods should be investigated. As part of Ground Vibration Testing, this paper presents an investigation on new innovative measurement methods that could improve and complement the current methods based on accelerometers. This report is structured in three parts; the first part gathers and presents some innovative measurement methods and the two following parts focus on experimentations of two measurement methods using rapids cameras and 3D laser scanners. / Flygtestning är ett viktigt steg av att utveckla ett flygplan. Genom en uppsättning tester blir varje ny eller modifierad flygkonfiguration certifierad. Certifiering garanterar säkerhet, kvalitet och pålitlighet. Avdelningen för flygtestning på Dassault Aviation är ansvarig för genomförandet av flygtester I Istres, södra Frankrike. Ett viktigt test före flygning är Ground Vibration Test (GVT). Målet med detta test är att mäta strukturens egenfrekvenser och lägesformer. Resultaten jämförs sedan med dem som ges av den finita elementmodellen för att kunna verifiera eller uppdatera dem. Att fastställa det strukturella beteendet är av stor vikt för flygplanets säkerhet; till exempel hjälper det att stipulera planets flygstabilitet och fladdergränsen. Under ostadiga aerodynamiska belastningar kan flygplanets struktur vara dynamiskt instabil, vilket innebär att svängningens amplitude ökar med med tiden. Resonansfenomenet som kallas för fladder kan allvarligt skada eller till och med leda till total förstörelse av flygplanets struktur. GVT: er utförs genom att utsätta flygplanet för svängande krafter på utsedda delar av planet. Sedan används hundratals accelerometrar för att mäta deformationerna. Genom att veta exakt inmatningsexitering och hur strukturen svarar, är det möjligt att beräkna förhållandena (de så kallade överföringsfunktioner) mellan de applicerade oscillerande krafterna och accelerationsåtgärderna. Denna mätmetod baserad på accelerometrar är mycket exakt; installationen tar emellertid mycket tid och skapar en viktig överbelastning på grund av ett stort antal accelerometrar och kablar som används. Som en del av markvibrationstest presenterar detta dokument en utredning om nya innovativa mätmetoder som kan förbättra, komplettera eller till och med ersätta de nuvarande metoderna baserade på accelerometrar. Denna rapport är strukturerad i tre delar; en kort konstnärligt samling där det presenteras några innovativa mätmetoder och sedan två delar med fokus på experiment av två mätmetoder med hjälp av rapids kameror och 3D-laser. Arbetet är ett första steg i en lång forskning som säkert på några år kommer att avföra accelerometrar och ersätta dem med nya metoder som är mycket bekvämare.

One of the biggest problems of our time is the global warming. A direct result of this phenomena is the melting of ice of the glaciers on the north and the south pole. As this continues, the melted ice will contribute to an increase of the sea level, and may cause enormous natural disasters. To be able to prevent this, it’s important to study its affects. This reports contains a concept study of a Unmanned Aerial Vehicle, a UAV, set on the coast of Antarctica by the Australian owned base Davis Station to document the changes and retracting of the glacier borderline. The purpose of the aircraft is to scout a pre-determined path whilst documenting the glaciers with photography from above.

This report covers the basic approach to creating a new multirotor design. All the way from creating a concept, through design requirements and finally evaluation. Both control algorithms and system design is covered. The main problem solved is that of the danger of naked propellers used on most multirotor drones and how to make them safer and easier to fly in populated areas.

The degree project we were assigned consists of designing an environment-friendly Unmanned Aerial Vehicle (UAV) that can fly at least one hour. In this case the type of energy used for power system is solar energy as a clean energy.

At higher altitudes is where we on occasion observe some of the most interesting atmospheric events in the sky. Examples of such are Aurora borealis, lightning sprites, jets and noctilucent clouds. In studying these processes one can learn much about them and our atmosphere in general but studying them is not always easy. Since atmospheric events of this scale cannot possibly be replicated in a laboratory environment they must be observed when they occur in our atmosphere. The ALPHA project's purpose is to (at a reasonable cost) design and build an UAV equipped with scientific instruments including a camera suitable for low-light imaging to be able to capture these fascinating phenomena. The aircraft will have a high cruising altitude of 15 km (lower part of the stratosphere). By making observations in flight above the troposphere, the limiting factor of weather is practically eliminated as compared to making ground-based observations.  In this 15 credits project, the thermal design aspects for the components of the UAV are explored. This mainly involves ensuring that the camera, batteries, and electronics are kept at a moderate temperature during flight. Another area that is explored is potential icing and its effects on the UAV.

The critical applications domain stands today at the brink of a great divide. On one side, the deterministic and safe operational prerequisite of the system. On the other, an ever increasing demand for computational power and miniaturization. In some cases, the welfare of people hinge in the balance of these attributes. It is therefore vital that these system undergo strict and rigorous development and testing. Development has evolved a great deal with regards to computational power and miniaturization. So too has the development of deterministic and safely operational systems. However the combination of these two are a complex matter. A light in the dark might be seen in the Commercial Off The Shelf System-on-Chip, which offers great computational power in relation to its volume. This thesis’s objective is to investigate potential fault-detection methods applicable on commercial System-on-Chip. To determine applicability, multiple implementations have been made and tested. Results from which suggest that fault detection methods implemented on field programmable gate array are highly effective. However, not all worst case execution time analysis conducted in this thesis are deemed a success. A common-mode analysis is conducted which indicated that functions already present on the System-on-Chip, before implementation, negated the effect of common-cause failures under scrutiny in the analysis. The majority of the data gathered from state of the art, implementations and common-mode analysis conducted, indicate that commercial off the shelf multi-processor System-on-Chip platforms have great potential in safety critical systems.

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Determining suitable controllers for the process of evaluating dynamic per-formance of multiple versions of an aircraft’s aerodynamical, geometric and propulsive properties in its conceptual stage is an expensive task.In this report a proposition is made to utilize a generalized feedback lin-earizing controller that o˙ers the aircraft designer valuable insight into the manoeuvre performance of their aircraft. This is carried out by first estab-lishing fundamental requirements for a controller capable of treating a generic airframe, and formulating the resulting control laws.It is shown in this report, that with a suÿciently simple aerodynamic and propulsive model explicit feedback linearization is possible with satisfactory performance and robustness. Whereas it would be necessary to implement INDI if explicit inverse mappings are not obtainable. Which in turn would introduce additional tuning parameters.Robustness verification is performed in two stages, firstly by introducing a high model uncertainty within the flight control system and showing, via simulation, that the control system successfully performs desired multi-axial manoeuvres whilst managing to maintain the induced side slip below 0.1◦. Secondly by disturbing the aircraft with a discrete side slip. Critical side slip disturbance angle was found to be considerably larger than that for regular aircraft entailing that the used case study may be somewhat over dimensioned with respect to yaw control authority.