This thesis explores the development of robust models for estimating fuel consumption in Unmanned Aerial Vehicles (UAVs), specifically focusing on the Skeldar V-200 Vertical Take-off and Landing (VTOL) system. The primary objective is to enhance mission planning and operational efficiency by accurately predicting Time to Empty (TTE) and Distance to Empty (DTE). Two main modeling approaches are employed: physics-based modeling, which leverages fundamental principles of vehicle dynamics and aerodynamics, and system identification modeling, which utilizes historical data to predict future performance. The results present a robust, physics-based model that predicts TTE and DTE, regardless of operating conditions, alongside a system identification model that quickly and accurately models the fuel consumption of the UAV under normal operating conditions. This research contributes to the field by providing a detailed analysis of model efficacy and practical application, suggesting pathways for future enhancements, and setting a foundation for more sophisticated predictive models that could significantly optimize autonomous UAV operations.

In the pursuit of reducing fuel consumption and meeting stringent emission regulations,controlling the air charge in heavy-duty vehicle combustion engines is critical. Instead ofthe traditional way of controlling an engine, which means using separate feed-forward andfeedback, this study explores the usage of a Nonlinear Model Predictive Control (NMPC). Anengine model, describing a physical engine, has been constructed and parameterized withdata from the engine manufacturer. Sub models were parameterized using the least squaremethods. With complete model parametrization, this report shows results of the minimizingof a cost-function that optimizes parameter values according to model-faults. Two solvers were used and compared for a simplified example, controlling a throttle.Both leading to similar results. One of the solvers were further used to control the completeengine model. The objective was to achieve a desired combustion, minimize losses andthereby reducing emissions. The NMPC was simulated in two different drive cycles. The results showed that a satisfactory engine model has to be used in the controller toachieve optimal control. Several results show that this method of controlling an engine canbe beneficial. / <p>B-huset, Plan 3</p>

The project was part of Airbus' drive to reduce the weight of the parts making up the Hinge 2 in the Keel Beam section of the A350 XWB-1000 by 15 kg. Although optimisation only led to a weight reduction of 4.5 kg, it was still decided to carry out a derisking study of the Hinge. To do this, the parts making up the Hinge had to be modelled in 2D and 3D finite elements using Hyperworks and according to the necessary meshing rules. This new mesh then had to be integrated into an overall mesh of the entire section of the Keel Beam. After recovering the critical safety margins and their loads from the certification files, it was necessary to run these loads on the new model in order to extract the dimensioning forces. These loads were then used to carry out the priority static studies using Hyperworks, Excel and Isami. Nine studies were carried out to ensure that the new geometry of the Hinge would hold up well. In the end, despite constraints such as the absence of contacts in the model studied, no safety margin fell below 1, which validates the static strength of the new Hinge. Finally, this project was very instructive, both personally and professionally, leading to become nearly completely autonomous as a calculation engineer. / Projektet var en del i Airbus strävan att minska vikten på gångjärnsdelar i en kölbalkssektion på A350 XWB-1000 med 15 kg. Även om endast 4,5 kg kunde reduceras i slutändan, genom optimering, beslutades det att genomföra en analys av gångjärnet för riskminimering. För detta modellerades de delar som utgör gångjärnet med 2D och 3D finita element i Hyperworks, under iakttagande av gällande rekommendationer för meshning. Beräkningsnätet behövde sedan integreras i ett övergripande nät för hela sektionen av kölbalken. Efter att ha hämtat de kritiska säkerhetsmarginalerna och deras belastningar från certifieringsfiler var det nödvändigt att analysera dessa belastningar i den nya modellen för att få fram de dimensionerande krafterna. Dessa laster användes sedan för att utföra de prioriterade statiska studierna med hjälp av Hyperworks, Excel och Isami. Nio studier utfördes för att säkerställa att gångjärnets nya geometri skulle uppfylla kraven. Analysen validerade den statiska styrkan hos det nya gångjärnetI, med reservation för begränsningar såsom avsaknaden av kontaktmodellering i den använda modellen. Ingen säkerhetsfaktor överskreds. Projektet var mycket lärorikt, både på det personliga och yrkesmässiga planet, till den punkt där jag blev praktiskt taget självständig som beräkningsingenjör.

There is a need to improve the JU Solar Team's new solar cell powered electric car's driving capabilities for the Bridgestone World Solar Challenge 2019. Partly to improve the car's safety and the ability to meet the competition requirements, but also to minimize effects that contribute to increased rolling resistance. The work is carried out at Jönköping Institute of Technology with support from ÅF Automotive in Trollhättan. The work aims to parameterize driving characteristics with engineering requirements, evaluate how the rolling resistance can be minimized, how negative driving characteristics can be minimized and a weight comparison with wheel suspension from 2017. This is the basis for the construction of the 2019 wheel suspension adapted for new body designed and manufactured in parallel with this work. The study includes performed measurements of the side force impact on steering angle change and camber change, calculation of load case, concept generation and evaluation, computer-aided strength evaluations. The results of the survey show great weaknesses in the 2017 solar car. In the case of an applied side force in the front wheel, a large wheel angle change occurs. This is largely due to under-dimensioned steering arms and the geometric design of the points. The influence of the side force on the steering angle has theoretically been reduced by at least 44% verified in CAD environment. In addition to this improvement, the entire wheel suspension system's attachments and sub-components are stiffer, which should contribute to an even greater improvement. The study also shows that the steering angle was insufficient to meet the competition requirements, which could be improved by 21.2% greater steering angle on the wheels. The spring and damper's operating ratio in comparison with the wheel has also been evaluated and has been able to be increased from 31% to 51.5%. This leads to reduced forces on the link arms and body by 20.5% during the same external load case. The study is limited to evaluating the hard points of the wheel suspension as well as the strength and design of the link arms, steering arm, suspension and damping attachment.

Kylvatten används för att kyla framdrivningsmaskineri och övrig utrustning med kylbehov ombord på fartyg. För att förhindra rost i den utrustning som skall kylas, måste kylvattnet behandlas. Som rostskydd används idag kemikalier. I samband med byte av kylvattnet, hamnar dessa kemikalier ofta i havet, vilket leder till negativ miljöpåverkan. I detta examensarbete har möjligheten att använda kemikaliefri vattenbehandling istället för kemikalier som rostskydd i system med vattenburen värmeöverföring undersökts. Kontakt med olika företag och en intervju med personal på ett fartyg med installerad elektromagnetisk vattenbehandlingsutrustning har gett information för undersökningen. Vi har också gjort egna mätningar på vatten i värmesystem med avjoniseringsutrustning och på tekniskt vatten behandlat med kemikalier. Mätningarna har använts för att undersöka hur vattnet påverkas av dessa behandlingsmetoder. Denna undersökning har inte resulterat i något entydigt svar på om kemikaliefri vattenbehandling kan ersätta kemikalier i kylvattnet till ett fartygs framdrivningsmaskineri, men visat att det är ett möjligt alternativ för mindre slutna system.

<p>Westhelicopter INC. has an aviation workshop providing qualified helicopter maintenance in accordance with PART-145. Maintenance and administrative base is situated in Luleå at Kallax airport. <strong>The types that Westhelicopter INC are currently authorised to service are: </strong>Eurocopter AS 350 Base/Line Maintenance, Eurocopter EC 120 Base/Line Maintenance and Robinsson R44 Base/Line Maintenance.</p><p> </p><p>The thesis work has been to make new maintenance programme for Westhelicopter INC. This maintenance programme will be used to follow-up the time of the components, service bulletins and ADs. Existing materials, as maintenance manuals and interviews with technical staff, was used to make more efficient maintenances programme. Work will be applied to all helicopters that Westhelicopter AB supplies.</p>

<p>Road conditions affect fuel efficiency and vehicle fatigue when driving heavy trucks. Information about traveled road conditions enable optimization of chassis configuration when driving, and logging of vehicle stress. Previous work on this topic focus mainly on tuning of active suspension parameters in the car industry. One conceivable application for heavy trucks is implementation of active chassis level control based on road conditions, with possible improvements in driving economy as result. Another is logging of usage conditions which helps explain vehicle faults caused by abnormal wear. This work examines the possibilities to use already on vehicle sensors for road roughness estimation. It also investigates what requirements existing signals must fulfill to ensure reliable estimates. Two methods for road roughness estimation are proposed using rear axle level sensor and a simple linear suspension system model.</p>

<p>To fulfill todays requirements on emissions from engines, SCANIA has developed an engine with EGR (Exhaust Gas Recirculation) and VGT (Variable Geometry Turbine). This gives two extra control signals to take into consideration. Open loop optimal control is used to investigate how these two actuators should be controlled to minimize emissions and fuel consumption. A cost function, consisting of the errors between the most important variables and their set points, has been used in the minimization. The variables are the torque, the EGR mass fraction, the oxygen/fuel ratio and the pumping losses.</p><p>From studies of the two control signals in different transients in the engine, information of how to control the VGT and EGR in the optimal way is found. The result from the optimal control has been compared with a PID simulation and has showed a better way to control the signals. The mayor reason why the optimal control is better than a PID controller is the ability to use future values from the transients.</p>

<p>Closed loop fuel injection have been in use for two decades but it's not until the recent five years that the wide band lambda sensor have been utilized. The goal is to explain wide band and discrete lambda sensors in a simple but powerful way. Both sensors are modeled by simple mathematics and accounts for Oxygen, Hydrogen and Carbon monoxide influences. The focus is not just on the output from the sensors, but also on the underlying function. This means that all explanations are thorough and methodical. The function of a wide band lambda sensor is more complicated than a discrete type lambda sensor, therefore it's harder to get correct readings. The model of the wide band lambda sensor is used to evaluate different problems in preparation for the development of an observer. Several potential problem sources are tested and investigated, these include calibration error, pressure error, air leak error, gas sensitivity and fuel errors. To evaluate the potential problems and their ability to explain differences between actual lambda and sensor output, two sensors with differing outputs have been used. The final result is implemented in an ECU.</p><p>The models indicate that the difference between the two sensors is most likely explained by different sensitivity for CO, O2 and H2. This can in turn have one or several explanations. It is suggested that different ability to pump oxygen, different nernst cells or even different controllers can cause this. The reason is not investigated further as this would require a very deep research on the two sensors. Because no usable explanation is found an observer that estimates the offset at stoichiometric conditions, where lambda equals one, is constructed. The observer uses the fact that the switch point of a discrete lambda sensor is insensitive to disturbances. The offset calculation is performed in real time on an ECU. Tools for calibration of the observer are also developed. With the observer the error for the two sensors is roughly halved over the whole spectrum and at stoichiometric conditions, which is the normal operation for an engine, the error was too small to measure.</p><p>Although the wide band lambda sensor is a very complex sensor it is shown that it can be understood with simple mathematics and basic knowledge in chemistry. The developed model agrees well with the real sensor for steady state conditions. For transient conditions, however, the model needs to be refined further. The question why the two sensors differ is discussed but the true origin of the cause remains unsolved. The conclusion is that the error can be drastically reduced with just an offset. It is also shown that when building a lambda sensing device the controller is of equal importance as the sensor element itself. This is due to the sensitivity of surrounding factors that the controller must be able to handle. These effects are specially important for engines running at lambda not equal to 1, for example diesel engines.</p>

<p>This thesis work was done in order to improve the capabilities in a preliminary aircraft analysis program, DIBA, at Saab Aerosystems. The areas that this was done are in the sizing and balance. One sizing tool was developed in order to make a performance analysis with the DIBA generated geometry and customer and/or regulation based criteria. A balance diagram, a neutral point estimation function, a landing gear plot and a trim program was created in order to extend the weight and balance analysis.</p><p>Results show that various aircraft both military and civil can be analyzed with good comparison to other analysis and reality. For example EXCEL implemented analysis and graphs over real aircrafts shown in the report.</p>