Searched for: contributor%3A%22Cowan%2C+K.J.+%28mentor%29%22
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Gwalani, Punit (author)
With a dedicated mission to the Martian moons, Phobos and Deimos, set to launch soon, there is a growing interest in further exploring these moons using low-thrust propulsion. This paper investigates the trajectory design for a sample-return mission from Deimos using fuel-free solar sail propulsion technology, aiming to maximize operational time...
master thesis 2024
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Goldman, Thomas (author)
This thesis proposes an unsupervised Physics-Informed Neural Network (PINN) for solving optimal control problems with the direct method to design and optimize transfer trajectories. The network adheres analytically to boundary conditions and includes the objective fitness as regularization in its loss function. A test scenario of a planar Earth...
master thesis 2023
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Posthuma de Boer, Tjomme (author)
Shape-based methods are used in the preliminary optimization of low-thrust trajectories to rapidly search large design spaces and provide initial guesses for higher fidelity methods. The optimization process benefits from the shape-based methods providing initial guesses as quickly and as optimal as possible. This work aims to improve the...
master thesis 2023
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Riha, Benno (author)
Using low-thrust propulsion for interplanetary space missions has the potential to allow for more payload for the same mass put into orbit compared to what impulsive propulsion would allow for. The disadvantages are found in mission planning, however, as the continuous nature of the thrust yields a more complex problem. One potential solution to...
master thesis 2023
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Andrade Castanheira, Francisco (author)
The optimization of interplanetary, low-­thrust trajectories is a computationally expensive aspect of preliminary mission design. To reduce the computational burden associated with it, surrogate models can be used as cheap approximations of the original fitness function. Training the surrogate models in a fully online manner can be done to...
master thesis 2022
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Puts, Elmar (author)
Many contemporary interplanetary missions use efficient low-thrust engines to reach the far corners of our Solar System. Their trajectories, however, have proven to be complicated to optimise due to the non-impulsive manoeuvres involved in low-thrust spaceflight. Even though shaping methods have been used extensively to reduce the computational...
master thesis 2021
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Saz Ulibarrena, Veronica (author)
The use of low-thrust propulsion for interplanetary missions requires the implementation of new methods for the preliminary design of their trajectories. This thesis proposes a method using the Monotonic Basin Hopping global optimization algorithm to find feasible trajectories with optimum use of the mass of fuel for the case in which the...
master thesis 2021
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Brederveld, Jan (author)
Various machine learning algorithms have been applied to find optimal lowthrust<br/>satellite trajectories, however, no fair comparison of their accuracy has been made yet. In this paper, two common and promising supervised machine learning algorithms are compared for their regression capacities:<br/>the artificial neural network and the...
master thesis 2021
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Gómez Pérez, Pablo (author)
In this thesis, a new method to approximate the cost function of Low-Thrust, Multiple-Gravity-Assist interplanetary trajectories using a Machine Learning surrogate is proposed. This method speeds up the optimization process without fine tuning of the surrogate parameters for every individual case. The computational cost of obtaining training...
master thesis 2020
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Martens, Sjors (author)
Preliminary design of low-thrust trajectories in the circular restricted three-body problem (CR3BP) frequently relies upon ballistic dynamical structures and optimization algorithms. A fundamental understanding of how these dynamical structures change due to presence of a low-thrust force may lead to trajectories that cannot be obtained...
master thesis 2020
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Benayas Penas, Miguel (author)
The Kuiper Belt is considered to be formed by remnants of the original Solar System, that is why exploration missions to that region are susceptible of having an enormous scientific impact. Nonetheless, it is far away from Earth, missions to KBO targets a significant challenge. Additionally, current methods to identify trajectories that...
master thesis 2020
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Stubbig, Leon (author)
Building on recent advances in the fields of low-thrust trajectory optimization based on shaping methods, Artificial Neural Networks, and surrogate models in Evolutionary Algorithms, an investigation into a novel optimization routine is conducted. A flexible Python tool to evaluate linked trajectories in a two-body model based on the hodographic...
master thesis 2019
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Kranen, Tommy (author)
With all major bodies within the Solar System explored by at least a single fly-by, modern-day missions are becoming increasingly more demanding, up to a point where classical chemical propulsion can no longer supply the required ∆V. Increasingly more is relied upon low-thrust propulsion, characterised by its (very) low thrust force; long...
master thesis 2019
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Bouwman, Lieve (author)
Low-thrust trajectories can benefit the search for propellant-optimal trajectories, but increases in modeling complexity and computational load remain a challenge for efficient mission design and optimization. An approach for developing models utilizing Gaussian Process (GP) regression and classification is proposed to perform computationally...
master thesis 2019
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Perdeck, Matthias (author)
In interplanetary space missions, it is convenient to have a second departure opportunity in case the first is missed. Two distinct approaches to minimizing the maximum of the two Delta-V budgets of such a trajectory pair, are developed. The first (‘a priori’) approach optimizes the variables of both trajectories at once. The second (‘a...
master thesis 2018
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Langemeijer, Koen (author)
The three-body problem (3BP) formulated by I. Newton has inspired many great mathematicians like L. Euler (1707-1783), J.L. Lagrange (1736-1813), K.G.J. Jacobi (1804-1851), W.R. Hamilton (1805-1865) and J.H. Poincaré (1854-1912) to develop mathematical studies, methods and theories in an attempt to solve this problem. Although these concepts...
master thesis 2018
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Van den Broeck, Michael (author)
The use of Taylor Series Integration (TSI) for the propagation of spacecraft trajectories and its combination with the relatively unknown Unified State Model (USM) coordinate system, resulting in the TSI-USM propagator, is known to allow fast propagation of interplanetary low-thrust trajectories. Unfortunately, the TSI-USM propagator is a...
master thesis 2017
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