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Full-Text Articles in Astrodynamics
High-Fidelity Low-Thrust Trajectory Determination Research And Analysis, Tyler Hill
High-Fidelity Low-Thrust Trajectory Determination Research And Analysis, Tyler Hill
Aerospace Engineering
This document discusses a numerical analysis method for low thrust trajectory propagation known as the proximity quotient or Q-Law. The process uses a Lyapunov feedback control law developed by Petropoulos[1] to propagate trajectories of spacecraft by minimizing the user defined function at the target orbit. A simplified propagator is created from the core mechanics of this method in MATLAB and tested in several user defined cases to demonstrate its capabilities. Several anomalies arose in test cases where variations in eccentricity, inclination, right ascension of the ascending node, and argument of perigee were specified. Solutions to these anomalies are discussed …
De-Orbiting Upper Stage Rocket Bodies Using A Deployable High Altitude Drag Sail, Robert A. Hawkins Jr., Joseph A. Palomares
De-Orbiting Upper Stage Rocket Bodies Using A Deployable High Altitude Drag Sail, Robert A. Hawkins Jr., Joseph A. Palomares
Aerospace Engineering
This report examines the effectiveness of a drag sail to de-orbit upper stage rocket bodies. Many other perturbations contribute to the de-orbiting of these rocket bodies, and these perturbations will also be discussed briefly. This paper will show the length of time needed to force the altitudes of various launch vehicle stages with varying drag area sizes to less than 100 km. The upper stage of the Delta IV launch vehicle in an orbit with an altitude of 500 km will naturally de-orbit in 720 days but when equipped with a 20 m2 drag sail, it will de-orbit in …
Investigating Various Propulsion Systems For An External Attachment For A Controlled-Manual De-Orbit Of The Hubble Space Telescope, Nelson De Guia
Investigating Various Propulsion Systems For An External Attachment For A Controlled-Manual De-Orbit Of The Hubble Space Telescope, Nelson De Guia
Aerospace Engineering
This reports explains the results for a proposed senior project. This project concerns the Hubble Space Telescope, and exploring the possibility of having an external propulsion attachment for a manual de-orbit. The Hubble Space Telescope was proposed to return to Earth via the Space Shuttle. Although, through the current U.S. Space Administration, the Space Shuttle has been retired before the Hubble Space Telescope was retrieved. By completing this project, the results could provide insight to what type of propulsion would best de-orbit the Hubble upon its retirement. Different propulsion systems were considered to attempt to determine an optimal attachment, varying …
Design, Fabrication, And Testing Of An Electromagnetic Rail Gun For The Repeated Testing And Simulation Of Orbital Debris Impacts, Jeff Maniglia, Jordan Smiroldo, Alex Westfall, Guy Zohar
Design, Fabrication, And Testing Of An Electromagnetic Rail Gun For The Repeated Testing And Simulation Of Orbital Debris Impacts, Jeff Maniglia, Jordan Smiroldo, Alex Westfall, Guy Zohar
Aerospace Engineering
An Electromagnetic Railgun (EMRG) was designed, built, and tested, capable of firing a projectile a 1 gram projectile at 650 m/s muzzle velocity. The EMRG utilizes an injector, a high voltage power supply, a capacitor bank, inductors and rails. The injector fires 2300 psig Nitrogen gas into the system to provide an initial velocity. The high voltage power supply charges the capacitor bank. The capacitor bank discharges the electric potential built up through the projectile while inside the rails in order to create the EMRG’s force. The inductors are used to pulse form the capacitor bank in order to get …