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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

The use of commercial Low Earth Orbit satellite systems to support DoD communications/

Stelianos, Haralambos. January 1996 (has links) (PDF)
Thesis (M.S. in Electrical Engineering) Naval Postgraduate School, December 1996. / "December 1996." Thesis advisor(s): Tri T. Ha and Vicente Garcia. Includes bibliographical references (p. 95-97). Also available online.
12

A guide to the establishment of a university satellite program

Stewart, Abbie Marie, January 2007 (has links) (PDF)
Thesis (M.S.)--University of Missouri--Rolla, 2007. / Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed May 16, 2007) Includes bibliographical references (p. 96-97).
13

An attitude and orbit determination and control system for a small geostationary satellite /

Thopil, G. A. January 2006 (has links)
Thesis (MScIng)--University of Stellenbosch, 2006. / Bibliography. Also available via the Internet.
14

An investigation of the fine-pointing control system of a soft-gimbaled orbiting telescope /

Morrell, Frederick R. January 1970 (has links) (PDF)
Thesis (M.S. in Electrical Engineering)--University of Virginia, March 1968. / "June 1970." Submitted in partial fulfillment of the requirements for the degree Master of Electrical Engineering, University of Virginia, Charlottesville, Virginia, March 1968.--Report documentation page. "NASA TN D-5829." "L-6988." Includes bibliographical references (p. 17). Also available online in PDF from NASA Technical Reports Server Web site.
15

Command generation for tethered satellite systems

Robertson, Michael James, January 2004 (has links)
Thesis (Ph.D.)--School of Mechanical Engineering, Georgia Institute of Technology, 2005. / Singhose, William, Committee Chair ; Banerjee, Arun, Committee Member ; Chen, Ye-Hwa, Committee Member ; Ebert-Uphoff, Imme, Committee Member ; Olds, John, Committee Member. Includes bibliographical references.
16

Analysis and design of the mechanical systems onboard a microsatellite in low-earth orbit an assessment study /

Solomon, Dylan Raymond. January 2005 (has links) (PDF)
Thesis (M.S.)--Montana State University--Bozeman, 2005. / Typescript. Chairperson, Graduate Committee: David M. Klumpar. Includes bibliographical references (leaves 220-221).
17

EXTENDED ORBITAL FLIGHT OF A CUBESAT IN THE LOWER THERMOSPHERE WITH ACTIVE ATTITUDE CONTROL

Moorthy, Ananthalakshmy Krishna 03 July 2019 (has links)
A wide variety of scientifically interesting missions could be enabled by orbital flight altitudes of 150 – 250 km. For the present work, this range of altitudes is defined as extremely Low Earth Orbit (eLEO). The use of low-cost nanosatellites (mass < 10 kg) has reduced the cost barrier to orbital flight over the last decade and the present study investigates the feasibility of using primarily commercial, off-the-shelf (COTS) hardware to build a nanosat specifically to allow extended mission times in eLEO. CubeSats flying in the lower thermosphere have the potential to enable close monitoring of the Earth’s surface for scientific, commercial, and defense-related missions. The results of this research show that the proper selection of primary and attitude control thrusters combined with precise control techniques result in significant extension of the orbital life of a CubeSat in eLEO, thus allowing detailed explorations of the atmosphere. In this study, the orbit maintenance controller is designed to maintain a mission-averaged, mean altitude of 244 km. An estimate is made of the primary disturbance torque due to aerodynamic drag using a high-fidelity calculation of the rarefied gas drag based on a Direct Simulation, Monte-Carlo simulation. The primary propulsion system consists of a pair of electrospray thrusters providing a combined thrust of 0.12 mN at 1 W. Results of a trade study to select the best attitude control option indicate pulsed plasma thrusters operating at 1 W are preferable to reaction wheels or mangetorquers at the selected altitude. An extended Kalman filter is used for orbital position and spacecraft attitude estimations. The attitude determination system consists of sun sensors, magnetometers, gyroscopes serving as attitude sensors. The mission consists of two phases. In Phase I, a 4U CubeSat is deployed from a 414 km orbit and uses the primary propulsion system to deorbit to an initial altitude within the targeted range of 244 +/- 10 km. Phase I lasts 12.73 days with the propulsion system consuming 5.6 g of propellant to deliver a ∆V of 28.12 m/s. In Phase II the mission is maintained until the remaining 25.2 g of propellant is consumed. Phase II lasts for 30.27 days, corresponding to a ∆V of 57.22 m/s with a mean altitude of 244 km. The mean altitude for an individual orbit over the entire mission was found to vary from a maximum of 252 km to a minimum of 236 km. Using this approach, a primary mission life of 30.27 days could be achieved, compared with 3.1 days without primary propulsion.
18

Datagram routing for low earth orbit satellite networks

Hu, Yurong. January 2001 (has links)
Thesis (M. Phil.)--University of Hong Kong, 2001. / Includes bibliographical references (leaves.
19

Development of a Control Moment Gyroscope controlled, three axis satellite simulator, with active balancing for the bifocal relay mirror initiative /

Kulick, Wayne J. January 2004 (has links) (PDF)
Thesis (M.S. in Astronautical Engineering)--Naval Postgraduate School, Dec. 2004. / Thesis Advisor(s): Brij N. Agrawal. Includes bibliographical references (p. 103-104). Also available online.
20

Historic thermal calibration of Landsat 5 TM through an improved physics based approach /

Padula, Francis P. January 2008 (has links)
Thesis (M.S.)--Rochester Institute of Technology, 2008. / Typescript. Includes bibliographical references (p. 239).

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