Spacecrafts
Space systems play a significant role in scientific research and are also experiencing a steady increase in interest in the industrial sector. control systems are an essential part of every space system and are necessary to successfully fulfill the mission objectives. These include the successful launch and landing of a carrier rocket, the precise orientation and alignment of satellites for measurement and communication processes as well as the navigation and stability of lunar or Martian landers. Research topics encompass:
- the modelling of space-rated hardware for the simulation of realistic spacecrafts for the control design
- the modelling of the space environment and celestial bodies for the simulation of realistic missionsdesigns
- the design of autonomous controls systems for all missionparts, e.g. launch and landing fo rockets, attitude control of satellites or orbital maneuvers
- the evaluation of the performance and robustness of the control system in order to be able to make mathematically sound statements in unexpected scenarios.
Topics
The Chair of Flight Mechanics and Flight Control currently offers the following topics for student research projects and theses. If you are interested, please get in touch with the contact person for the relevant topic. Please refrain from multiple requests.
Motivation:
The sloshing behavior in the main tanks of a liquid rocket has a significant influence on its flight dynamics and can lead to the loss of the rocket in extreme cases. It is therefore important that these effects are taken into account when designing the controller for a rocket in order to guarantee the success of the mission. As part of this research project, an already non-linear simulation environment of the chair is to be expanded to include sloshing dynamics.
Task definition:
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Literature research on the modeling of fuel sloshing at different mission times (launch, stage separation, landing)
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Literature research on active/passive damping methods and their modeling
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Derivation of a model for propellant sloshing in the main tanks of a liquid rocket for v
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Implementation in a non-linear simulation environment in Matlab/Simulink
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Design of a controller for active damping of the propellant slosh
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Verification through reference missions
Contact person:
© M. Kretschmar
Research Assistant
NameDipl.-Ing. Frederik Thiele
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Language:
This project is only available in english.
Motivation:
When testing attitude control algorithms on a satellite model it is important that the model is a realistic representation of the real system. As spacecraft systems become more complex with more stringent performance requirements, the simulators require more realistic disturbance models. Torque disturbances for satellites are often modelled as shaped white noise. In reality, the disturbances are periodic and are influenced by the satellite’s attitude and orbital position. This project aims to develop a realistic torque disturbance model, taking into account influences from solar radiation, gravity gradient, Earth’s magnetic field and aerodynamic drag.
Task description:
- Develop a workplan for the project
- Review literature on at least the following topics:
- state-of-the art techniques for satellite simulation
- Torque disturbances experienced in space
- Model validation
- Develop a (parameterised) disturbance model in Matlab/Simulink
- Validate the disturbance model
Contact person:
© S. Ellger
Research Assistant
NameMs Emily Burgin M.Eng.
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Language:
This project is only available in english.
Motivation:
When testing navigation and control algorithms on a satellite model it is important that the model is a realistic representation of the real system. As spacecraft systems become more complex with more stringent performance requirements, the simulators require more realistic sensor models. Star trackers are used to measure the spacecraft’s attitude. They experience several types of noise that are often modelled as shaped white noise. In reality, the noises are highly dependent on the spacecraft’s rotational speed and visibility of the stars. Moreover, when the star-tracker is blinded by the sun, or shaded by the Earth, the navigation algorithm must be able to continue to function. This project aims to develop a realistic, parameterised star tracker model, for the purpose of testing control and navigation algorithms on a satellite simulator.
Task description:
- Develop a workplan for the project
- Review literature on at least the following topics:
- state-of-the art techniques for sensor modelling
- industry practice for star-tracker use
- model validation
- Develop a star tracker model in Matlab/Simulink
- Validate the model
Contact person:
© S. Ellger
Research Assistant
NameMs Emily Burgin M.Eng.
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Motivation
Control systems for the autonomous landing of reusable rocket stages or on celestial bodies such as the moon or Mars must demonstrate a high degree of robustness and reliability. In most cases, test runs on the real object are not practically feasible without taking high financial risks due to a potential failure. The VTOL (Vertical Take-Off and Landing) test platform EAGLE (Environment for Autonomous GNC Landing Experiments) developed by the German Aerospace Center (DLR) offers the possibility of testing planned controller architectures ahead of time on a system with comparable, generally unstable system dynamics.
These capabilities are to be extended to imitate the real behavior of spacecraft and thus verify the controllers designed for the mission. For this purpose, a flight controller is to be developed as part of this student project/diploma thesis, which adaptively compensates the forces from gravity and air resistance that are not representative for the mission in the flight test and also simulates inertia, vibration dynamics (flexible attachments, sloshing, etc.) and performance limitations of the real spacecraft.
Task description
- Literature research
- Comparison of the flight dynamics of EAGLE and the lunar module
- Design of a controller in Matlab
- Documentation
© S. Ellger
Research Assistant
NameDipl.-Ing. Carl-Johann Winkler
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Motivation
Control systems for the autonomous landing of reusable rocket stages or on celestial bodies such as the moon or Mars must demonstrate a high degree of robustness and reliability. In most cases, test runs on the real object are not practically feasible without taking high financial risks due to a potential failure. The VTOL (Vertical Take-Off and Landing) test platform EAGLE (Environment for Autonomous GNC Landing Experiments) developed by the German Aerospace Center (DLR) offers the possibility of testing planned controller architectures ahead of time on a system with comparable, generally unstable system dynamics. In the future, the capabilities will be expanded to imitate the real behavior of spacecraft and thus verify the controllers designed for the mission.
The EAGLE's main thrust system currently consists of a kerosene-fueled turbine. This results in a high level of complexity in operation and maintenance, as well as in ensuring safe flight operations with high operating costs and low flexibility. For this reason, a conversion to a comparably powerful electric propulsion system is to be conceptually explored as part of this student project/diploma thesis. This should be able to be operated by built-in batteries, but also by cable if longer test campaigns with short distances are planned. The aim of the work is to find a configuration of a purely electrically powered EAGLE that represents an optimal compromise between capabilities and the effort/cost of the conversion.
Task description
- Analysis of the existing thrust system
- Research into the electrification of the thrust system
- Detailed comparison of possible conversion variants
- Selection and documentation of the best configuration
© S. Ellger
Research Assistant
NameDipl.-Ing. Carl-Johann Winkler
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Motivation
The optimization of trajectories for space missions is of fundamental importance for fuel-efficient operation. The optimum trajectory is calculated in advance from the launch of the rocket to (for example) landing on the moon and updated during the mission via an existing data link in order to compensate for any deviations. While in the past, landing fields on the moon could be several hundred square kilometers in size, the aim with regard to future moon bases is to achieve significantly higher landing accuracy, so-called pin-point landings. This involves analyzing the landing area in a short time intervals during approach, selecting an optimal landing site and calculating a feasible trajectory. Due to the large distance, active trajectory optimization calculations on earth are no longer a feasible solution for the highly dynamic phase of the final approach of the lander.
Within the scope of this student project/diploma thesis, a real-time capable solution for image-based trajectory optimization for the final approach is to be developed. In a first step, a camera image is analyzed with regard to the relative position of the landing field to the spacecraft. The result is then used as the basis for a convexified optimization problem to generate an updated trajectory, taking into account the limitations in the dynamics of the spacecraft.
Task description
- Literature research
- Image analysis for landing site localization in Matlab
- Convex trajectory optimization in Matlab
- Simulation of continuous operation in Matlab/Simulink
- Documentation
© S. Ellger
Research Assistant
NameDipl.-Ing. Carl-Johann Winkler
Send encrypted email via the SecureMail portal (for TUD external users only).
If you are still unsure about your topic, we are also happy to offer general advice. Alternative options can also be presented based on the student's individual interests. We are also happy to support student theses with industry partners or initiative topics suggested by students. The contact person for projects about spacecrafts is:
© S. Ellger
Research Assistant
NameDipl.-Ing. Carl-Johann Winkler
Send encrypted email via the SecureMail portal (for TUD external users only).