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Engineering Commons

Open Access. Powered by Scholars. Published by Universities.®

2019

Theses/Dissertations

Air Force Institute of Technology

Low Earth Orbits

Articles 1 - 2 of 2

Full-Text Articles in Engineering

Limited-Duty-Cycle Satellite Formation Control Via Differential Drag, Talon A. Townley Mar 2019

Limited-Duty-Cycle Satellite Formation Control Via Differential Drag, Talon A. Townley

Theses and Dissertations

As CubeSat formation flying missions relying on differential drag control become increasingly common, additional missions based on this control must be studied. A mission planning tool is investigated to control the relative spacing of a CubeSat formation where differential drag is the sole control mechanism. System performance is investigated under varying perturbations and a range of system parameters, including limiting the control duty cycle. Optimal solutions based on using a pseudo spectral numerical solver, GPOPS-II, to minimize maneuver time. This study includes the development of a mission planning tool to work with the modeled CubeSat mission to calculate optimal maneuvers …


Comprehensive Study Of Study Of Optimal Synergetic Skip Entries With Dynamic Thrust Vectoring Control, Jeremiah M. Webb Mar 2019

Comprehensive Study Of Study Of Optimal Synergetic Skip Entries With Dynamic Thrust Vectoring Control, Jeremiah M. Webb

Theses and Dissertations

The atmospheric skip entry has been studied since London's presentation in 1962 describing a more fuel efficient means of altering the orbital inclination of satellites. Since London, research over the decades since has traversed many aspects of this field with varying degrees of success. The present research employs the use of modern optimal control software, complex dynamics with minor simplifications, and thrust vectoring to re-approach the aerocruise atmospheric skip entry. Using the aerodynamics of the X-34, the aerocruise problem is first compared to the un-powered aeroglide where it is shown that the aerocruise is capable of increasing the inclination change …