In Space Situational Awareness (SSA), it is crucial to assess the uncertainty related to thestate vector of resident space objects (RSO). This uncertainty plays a fundamental role in, forexample, collision risk assessment and re-entry predictions. A realistic characterization of thisuncertainty is, therefore, necessary.The most common representation of orbital uncertainty is through a Gaussian (or normal)distribution. However, in the absence of new observations, the uncertainty grows over timeand the Gaussian representation is no longer valid under nonlinear dynamics like spacemechanics. This study evaluates the time when the uncertainty starts becoming non-Gaussianin nature. Different algorithms for evaluating the normality of a distribution were implemented andMonte Carlo tests were performed on them to assess their performance. Also, the distancesbetween distributions when they are propagated under linear and nonlinear algorithms werecomputed and compared to the results from the Monte Carlo statistics tests in order to predictthe time when the Gaussianity of the distribution breaks. Uncertainty propagation using StateTransition Tensors and Unscented Transform methods were also studied. Among theimplemented algorithms for evaluating the normality of a distribution, it was found thatRoyston’s method gives the best performance. It was also found that if the Normalized L 2distance between the linear and non-linear propagated distributions is greater than 95%, thenuncertainty starts to become non-Gaussian. In the best case scenario of unperturbed two-bodymotion, it is observed that the Gaussianity is preserved for at least three orbital periods in thecase of Low-Earth and Geostationary orbits when initial uncertainty corresponds to the meanprecision of the space debris catalog. If the initial variances are reduced, then Gaussianity ispreserved for a longer period of time. Time for which Gaussian assumption is valid on orbitaluncertainty is also dependent on the initial mean anomaly. Effect of coordinatestransformation on Gaussianity validity time is also analyzed by considering uncertainty inCartesian, Keplerian and Poincaré coordinate systems. This study can therefore be used to improve space debris cataloguing.

The advantages of Topology Optimization (TO) are realized to a large extent due to the manufacturing freedom that Additive Manufacturing (AM) offer, compared to more conventional manufacturing methods. AM has the advantage of manufacturing shallow and complex structures previously not possible, and consequently opens up a whole new design spectrum. This thesis investigates the possibilities of using Topology Optimization as a tool to find stronger and lighter designs for the inlet turbine manifold in the rocket engine demonstrator Prometheus. The manifold is optimized by giving it more mass, subjecting it to load cases and pushing the topology optimization to make the manifold meet the weight requirement without exceeding the yield strength. Result validation indicates that the pressure and thermal loadings are the most prominent. The current topology optimization tools in ANSYS do not support optimization due to thermal features and thus optimization in the presented work has only been able to consider static structural loads. Nevertheless, it is possible to optimize the manifold due to static structural loads and achieve a manifold which satisfies the weight requirement. However, optimization tools due to thermal loading would be a desirable feature in the future.

The goal of this thesis was to both theoretically and experimentally show the effect of a plasma actuator for flow separation control.  In the theoretical part a solver was implemented in MATLAB code, to solve the governing equations describing the plasma actuator.  The experimental part included PIV (Particle Image Velocimetry) measurements of the velocity field induced by the plasma actuator, visualization of the effect in a wind tunnel and the development of a simple model of the plasma actuator based on the empirical result whose purpose is to be used in CFD (Computational Fluid Dynamics). The PIV measurements were performed with an acceptable result even though a lot of disturbance occurred in and near the plasma region.  The empirical result was used to develop the empirical plasma actuator model for CFD, which showed some interesting result.  The model implies that the induced force by the plasma actuator grows exponential with the applied peak-to-peak voltage.   The model was also used to predict airfoil performance with plasma actuators which showed an increase of the lift coefficient on a NACA0012 with a chord length of 0.1m.  Simulations were done for free-stream velocities up to 20m/s with three different configurations, without plasma actuator for comparison, with one actuator at the quarter-chord and one with three actuators on the airfoil.  With three actuators the increase of the lift coefficient was 108 percent at 5m/s and 14 percent at 20m/s. The simulations with one actuator were only performed up to 10m/s were the effect of the actuator still could be seen but for higher velocities the effect would probably be minor. The wind tunnel experiment clearly showed the effect and the advantages of utilizing plasma actuators for flow separation control.  The experiment showed that a single plasma actuator placed at the quarter chord of a fully stalled NACA0012 airfoil with a chord length of 0.1m, at approximately 20 degrees angle of attack and with a free-stream velocity of 1.5m/s, was able to reattach the flow behind the actuator. The result of the theoretical part was inconclusive, the code could not run with the appropriate voltage and frequency of the plasma actuator.  Some result was however obtained, implying that the time-average force induced by the plasma actuator was in the expected direction.  The theoretical model is however considered to have potential, the major problems concern the code which requires further development.

The image sensors embedded in the instruments on board of different satellites are a key aspect in the success of a mission of any type such as Earth observation, astronomy or planetary and universe exploration. The quality of the sensor itself as well as the electronics embedded in the instrument suffer from aging, not only due to the usage, but also due to the space environment factors. The outer space harsh environment is composed of charged particles with an incredibly high energy that can get through the shielding of the spacecraft thus causing damage to the sensors, or any part of the spacecraft. After a satellite is placed in orbit, there is no other way to check on its condition than to analyse the data transmitted to the ground stations.   It is well known that we can measure the evolution of the instrument’s detection unit by measuring the variation of the quality of the images taken in orbit. As it has been done in past work, the atypical behaviour can be detected at a pixel level by analysing the images taken in orbit, preferably in complete darkness to discard any parasitic light. Past analysis of the dark images from the sensors on board the Picard, SPOT4 and Sentinel2A mission, proposed a classification of the different atypical behaviour that a pixel can show, such as hot, transitory-hot or RTS. By the end of the mission this defects may even be present in several pixels.   The purpose of this work is to process the dark images obtained on orbit, at the end of the mission PLEIADES, to better understand the behaviour both Panchromatic and Multispectral CCD sensors and the differences in performance with respect to the tests made previously on ground. For this, a description of the framework of the PLEIADES mission and the technical design aspects of the CCD sensors on board are presented. Subsequently, the different image processing techniques used and developed are described, along with the tests made to get to the positive conclusion of no major anomalies detected in the PLEIADES images sensors. The analysis is done by means of new set of functions adjusted to the structure of the data, as well as the same detection software used in the previous analysis. Finally, a discussion is presented along with a further perspective for the analysis of future sets of data.

The Aouda.X Space suit simulator, developed by The Austrian Space Forum( OeWF) currently consists of a system that weighs 48 kg of which nearly 57% is comprised of the Suit's HUT (Hard Upper Torso), PLSS (Portable Life Support System) and OBDH (On- board data handling). In addition to this, the current conguration requires 3 hours of assisted donning/doffing. To improve the ergonomics of the design, a relatively lighter HUT/PLSS design prototype with efficient donning capabilities, preferably self -donning, must be developed. This issue can be addressed by proposing a Rear - Entry Design that when implemented on the Aouda.X, can potentially ease these impediments.This study aims at identifying a suitable Rear entry closure design for the current conguration of Aouda.X based on planetary suit performance indicators and operational requirements. The Aouda.X rear entry design is also targeted to be compatible with the NDX -Suitport developed by the University of North Dakota's Human Space Flight Laboratory. The thesis work comprises of the development of a suitable methodology to distinguish a rear entry design for the HUT and PLSS of the spacesuit simulator with the identication of a self-sealing/locking mechanism based on these requirements. A full scale CAD model of the HUT and PLSS with optimal dimensions of compatibility for the Spacesuit with the suitport is designed as a result of this study. Static load bearing analysis is performed to validate the feasibility of the structure and make suitabe recommendations for choice of materials. Methods for further improvement for rear entry suit development are outlined.

The International Space Station provides a high-quality of microgravity and extended exposure time which makes it a platform of choice for microgravity research. In order to increase accessibility of onboard experimentation, Space Applications Services will soon launch the ICE Cubes facility as part of its ICE Cubes Service. The facility is foreseen to host standardized plug-and-play payload cubes to reduce overall cost and procedure time required to install payloads on the station. To remotely support the facility it is decided to develop a utility cube named Cube-Zero that will be launched and installed with the facility on the station. This thesis work included the complete design, development and documentation of the cube. The thesis started by conducting a preliminary needs and market study from which two specific purposes were defined for the cube. In addition to its original function of support-utility, the cube is tasked to be a technical commercial demonstrator for the service. This led to the conceptual design of the cube as a multidisciplinary framework able to host two user-defined experiment modules. The preliminary concept was further refined in this paper and with support of prototypes, simulations and analyses led to a final functional design for the Cube-Zero. The work is concluded with the manufacturing of an engineering model of the cube. The model is fully operational, can support the test of the facility before launch and can demonstrate to users its versatility and ease of use in operating any kind of experiment module. Eventually, the information gathered in this thesis report will support future users into developing their own Cube-Zero payload module and guide Space Applications Services into manufacturing, testing and operating the Cube-Zero protoflight model. / ICE Cubes

Denna litteraturstudie behandlar Safety Managment System (SMS), ett relativt nytt begrepp och arbetssätt inom flygindustrin för att arbeta med flygsäkerhet och som initierades av det som idag är International Civil Aviation Organization (ICAO), ett organ inom Förenta Nationen (FN). SMS utvecklades eftersom det i flygsäkerhetsarbetet har blivit allt svårare att utpeka enskilda faktorer som orsakar olyckor, utan är i större grad en kedja av faktorer när en olycka inträffat. SMS är en systematisk metod för att hantera säkerhet, inklusive de nödvändiga organisatoriska strukturer, ansvarsområden, riktlinjer och rutiner. SMS omfattar säkerhetspolicy och mål, riskhantering, säkerhetsförsäkran samt säkerhetsfrämjande. Transportstyrelsen publicerade 2013 ett svenskt State Safety Program (SSP) med krav på SMS inom andra verksamhetsområden inom flyget. European Aviation Safety Agency (EASA) publicerade 2013 ett förslag där SMS skulle krävas hos flygunderhållorganisationer (Part-145), vilket ej än har fastställts och publicerats. Syftet var att tydliggöra hur implementeringsarbetet fortgår för SMS inom svenska Part-145 organisationer, vilka faktorer som kan försvåra arbetet, samt att belysa möjligheter och utmaningar vid implementering av SMS. Även att få en förståelse i skillnaden mellan dagens säkerhetsarbete i förhållande till vid implementerat SMS inom flygunderhåll. Arbetet begränsades till SMS i Svenska flygindustrin och inom flygunderhåll Part-145 och arbetet baseras på källor från ICAO, EASA, Transportstyrelsen, relevant litteratur och forskning samt en kvalitativ intervju med representant på Transportstyrelsen. Slutsatsen är att det finns i dagsläget starka indicier på att EASA kommer att publicera ett lagförslag sommaren 2018 som gäller för underhålls-organisationer (Part-145) och att dessa organisationer då kommer att ha en tvåårsperiod för implementering. Vidare krav på rapportering, riskbedömning och tydligt krav på dokumentering är viktiga skillnader mellan dagens krav och de nya kraven i och med SMS. Vidare kan man konstatera att risken vid implementering av SMS är att man överkomplicerar implementeringen, inte anpassar systemet till egna organisationen, att rutiner sedan inte används alternativt otillräckligt med resurser eller att man efter implementering inte kontinuerligt arbetar med SMS. Vi kan även slå fast att framgångsfaktorer för att erhålla ett fungerande SMS inkluderar utbildning och engagerad ledning samt att SMS anpassas för organisationens verksamhet och blir väl integrerat i de dagliga aktiviteterna. / This literature study covers the Safety Management System (SMS), a relatively new concept and working method within the aviation industry to work with flight safety and initiated by what is now the International Civil Aviation Organization (ICAO), a United Nation (UN) specialized agency. SMS was developed since work with flight safety has become increasingly difficult to identify individual factors that cause accidents, but to a greater extent a chain of factors when an accident occurred. SMS is a systematic approach to managing safety, including the necessary organizational structures, responsibilities, policies and procedures. SMS includes safety policy and objectives, risk management, safety assurance and safety promotion. The Swedish Transport Agency published in 2013 a Swedish State Safety Program (SSP) with requirements for SMS in other areas in aviation. European Aviation Safety Agency (EASA) published in 2013, a proposal with requirements of SMS to the maintenance organizations (Part-145), which has not yet been established and published. The objective was to clarify how the implementation work continues for SMS in Swedish Part-145 organizations, the factors that can complicate the work, as well as highlighting opportunities and challenges in the implementation of the SMS. Also to get an understanding of the difference between today's safety work in relation to the implemented SMS in aviation maintenance. The work was limited to SMS within Swedish aviation industry and maintenance Part-145 and the work is based on sources from ICAO, EASA, Swedish Transport Agency, relevant literature and research as well as a qualitative interview with a representative of the Swedish Transport Agency. The conclusion is that there is at today strong indications that EASA will publish a legislative proposal the summer of 2018, which applies to maintenance organizations (Part-145), and that these organizations will then have two years to implement the new requirements. Further reporting requirements, risk assessment and clear demands on documentation are important differences between today's requirements and the new requirements of the SMS. Furthermore, it can be stated that the risk in the implementation of SMS is that it complicates implementation more than needed, do not customize the system to their own organization, the routines then will not be use alternative insufficient resources, or that after the implementation the organization do not continuously work with the SMS. We can also conclude that the success factors to obtain effective SMS includes education and management commitment and that the SMS adapts to the organization's operations and is well integrated in the daily activities.

By enabling coordinated task execution and movement, robotic swarms can achieve efficient exploration or disaster site management. When utilizing Ultra-wideband (UWB) radio technology for ranging, the proposed relative localization sensor can be made lightweight and relatively indifferent to the ambient environment. Infrastructure dependency is eliminated by making the whole sensor fit on a swarm agent, while allowing for a certain amount of positional error. In this thesis, a novel algorithm is implemented in to constrained hardware and compared to a more traditional trilateration approach. Both algorithms utilize Particle Swarm Optimization (PSO) to be more robust towards noise and achieves similar accuracy, but the proposed algorithm can run up to ten times faster. The antenna array which forms the localization sensor weighs only 56g, and achieves around 0.5m RMSE with a 10Hz update rate. Experiments show that the accuracy can be further improved if the rotational bias observed in the UWB devices are compensated for.

This thesis presents a wireless communication system for intra-satellite communication based on Bluetooth Low Energy technology, which can have many benefits regarding the design and operation of satellites. The proposed design based on the nRF53832 chip from Nordic Semiconductor is described, followed by the results of several tests regarding the most important design criteria for its application in small satellites. The tested aspects include the power consumption of the wireless module in different operation modes, which is sufficiently low for the application even in small satellites. Signal strength measurements for various output power settings and obstacles show that reliable communication is possible in a satellite mockup. No packet error was detected, and latencies of less than 30 ms combined with achievable data rates between 200 and 700 kbps should be sufficient for most CubeSat satellites. Additionally, details are given to successfully integrate the chip with existing satellite subsystems. A code library is provided to simplify the communication between the modules, and a concept of a redundant system is established to increase the reliability for critical satellite subsystems. The overall assessment of the technology suggests that the presented system is suitable for in-orbit deployment with the Aalto-3 satellite (currently being developed at Aalto University), which will provide further validation of the technology.

A human brain is capable to achieve great things, to endure heavy stress and to calculate complex problems. What happens when it fails to do so? Is there anything that could be done to prevent this from happening? Is it possible to help a pilot in command manage his or her stress during flight by measuring finger temperature, skin conductance, ECG and heart rate variations? This thesis study processes that can help pilots manage high stress with simple tools such as closing their eyes and taking a few deep breaths. To determine when the calming measures are needed and to evaluate potential effects, all the signal data stated above are used combined with scoring of every participant performance. The statistical methods used involves an ANOVA-test and mean value calculations. The results were also analyzed using CBR to get a better understanding of the results and to not only rely on statistical methods. The thesis is limited to a minor study of 10 student pilots participating in two sessions with a heavy workload departure in a simulator. The test did result in a small difference between the two sessions which pointed at the calming measures giving a slight improvement for the pilots. However, when ANOVA was applied it showed that the difference between the two sessions was not a significant one. This could be due to several reasons; the pilots were not used to the calming measures and because of this felt more stressed when trying to use the calming measures as well. There might have been a difference if calming measures were included into pilot training already from the beginning. Another reason might be because this is only a minor study and the difference was not apparent on so few participants. In future research, however, there might be a breakthrough on how to handle stress in a cockpit environment involving similar sensors.