Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 14 of 14 for “"orbital transfer"”.
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Orbital transfer trajectory optimization
… rocket engines for spacecraft. Optimizing the orbital transfers for low thrust engines is significantly more complicated than optimizing transfers for impulsive engines because a continuous control law must be found and long integrations are necessary to determine whether the control law works …
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Optimal orbital transfer using a Legendre pseudospectral method
Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 2003.
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Aero-assisted orbital transfer vehicles utilizing atmosphere ingestion
Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 2001.
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Systems analysis of an ion-propelled orbital transfer vehicle
… design configuration for an ion-propelled orbital transfer vehicle system. The four components of the system are: ground software, ground hardware, the orbital transfer vehicle and the space shuttle. The orbital transfer vehicle uses electrostatic propulsion to transfer payload satellites …
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Cost and technology assessment of low thrust orbital transfer vehicles
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 1994.
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Architecting a family of space tugs based on orbital transfer mission scenarios
… that service groups of satellites with similar orbital and physical characteristics, rather than to design a "monster" vehicle expected to traverse the huge distances between LEO and GEO and deal with satellites of all types and sizes. Thus, the approach of this work was based on the exploration …
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Approximate heat-transfer and wall-temperature calculations for aeroassisted orbital transfer vehicles
… a method for the calculation of Convective heat-transfer and surface temperatures on heat-shields of Aeroassisted Orbital Transfer Vehicles (AOTVs) in hypersonic flow regimes. Inviscid flowfield solutions are obtained about the aerobraking shield on the AOTVs using axisymmetric Euler's equations. …
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Optimal trajectories for hypervelocity flight
… hypervelocity flight of interest in aeroassisted orbital transfer. Both coplanar orbital transfer and noncoplanar orbital transfer are studied. For these cases, the GEO-to-LEO transfer, the HEO-to-LEO transfer, and the LEO-to-LEO transfer are considered in connection with a spacecraft which is …
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Modeling and Experimental Measurements of Laser-Sustained Hydrogen Plasmas
… propulsion concept especially applicable to orbital transfer vehicles. As an alternative to combusting fuel and oxidizer, the concept utilizes a remote laser beam as a source of power. A laser sustained plasma (LSP) is the medium by which power is absorbed by the beam and transferred to the …
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Piecewise-constant control strategies for use in minimum fuel aeroassisted orbital transfers
… use of aerodynamic forces to assist in certain orbital transfers can greatly reduce the fuel consumption as compared with corresponding all-propulsive transfers. Therefore, in seeking minimum fuel trajectories, aeroassisted transfers need to be investigated. A review of the current literature …
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Machine learning-aided trajectory optimization and tour design
… evaluates several ML-aided frameworks for rapid transfer approximation, flyby-sequence optimization, and reinforcement-learning-based trajectory optimization. First, a neural-network-based Lambert approximator is developed to provide rapid estimates of transfer legs needed for large-scale …
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Results of true-anomaly regularization in orbital mechanics
… the initial and final state vector on the transfer arc can be related to each other by rational algebraic formulae; no other transcendental function is needed. When the two problems are generalized by variation of parameters to the case of oblate-gravity perturbed motion, it is found that, …
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Generalized multi-commodity network flows : case studies in space logistics and complex infrastructure systems
… "gateway" resource depots at GTO and DTO with orbital transfer vehicles (OTVs) running in the cislunar and Martian systems. Then we solve variant problems that have different settings to see the effect of each factor. Findings include: taking advantage of oxygen-rich ISRU, LOX/LH2 is preferred …
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Performance Analysis of Direct and Indirect Formulations of the Legendre Pseudospectral Method for the Optimization of Spacecraft Trajectories
L'abstract è presente nell'allegato / the abstract is in the attachment