Sökning: "rymd"

Visar resultat 1 - 5 av 256 avhandlingar innehållade ordet rymd.

1. 1. Attitude and Trajectory Estimation for Small Suborbital Payloads

   Författare :Yunxia Yuan; Nickolay Ivchenko; Gunnar Tibert; Rafael Wisnewski; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; free falling; least squares optimization; unscented Kalman filter; Flyg- och rymdteknik; Aerospace Engineering;

   Sammanfattning : Sounding rockets and small suborbital payloads provide a means for research in situ of the atmosphere and ionosphere. The trajectory and the attitude of the payload are critical for the evaluation of the scientific measurements and experiments. LÄS MER

3. 2. Enhanced Composite Joint Performance through Interlacement of Metal Inserts

   Författare :Sahar Akbarpour; Stefan Hallström; Conor McCarthy; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Aerospace Engineering; Flyg- och rymdteknik;

   Sammanfattning : The work in this thesis investigates bolted joints in fibre reinforced composites with particular focus on a novel insert concept. The concept is characterised by replacing all composite plies with stacked metal patches, locally around a bolt hole, so that they jointly form a solid metal reinforcement. LÄS MER

4. 3. Improving Fixed Wing UAV Endurance, by Cooperative Autonomous Soaring

   Författare :Klas Andersson; Petter Ögren; Fredrik Bruhn; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; UAV; Autonomous soaring; Cooperative soaring; Computer Science; Datalogi; Flyg- och rymdteknik; Aerospace Engineering;

   Sammanfattning : The ever-expanding use and development of smaller UAVs (Unmanned Aerial Vehicles) has highlighted an increasing demand for extended range and endurance for this type of vehicles. In this thesis, the development of a concept and system for autonomous soaring of cooperating unmanned aerial vehicles is presented. LÄS MER

5. 4. The flight perturbation problem : operational aircraft rescheduling

   Författare :Tobias Andersson; Linköpings universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

   Sammanfattning : When there is a perturbation in a carefully planned flight schedule, e.g. an aircraft breakdown, it is important to minimize the negative consequences of this disturbance. In this thesis, a model and a number of solution strategies for the Flight Perturbation Problem is presented. LÄS MER

7. 5. Computational Modelling for Cavitation and Tip Vortex Flows

   Författare :Abolfazl Asnaghi; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Cavitation; SST k − ω; OpenFOAM; Propeller; LES; Numerical simulation; Cur- vature correction; Elliptical foil; Inception; Twisted Delft foil;

   Sammanfattning : Cavitation often brings negative effects, such as performance degradation, noise, vibration, and material damage, to marine propulsion systems, but for optimum performance, cavitation is almost inevitable. Therefore, it is necessary to better understand cavitation in order to maximize the performance without encounter- ing severe problems. LÄS MER