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Thesis (M.S. in Astronautical Engineering)--Naval Postgraduate School, December 2006. / Thesis Advisor(s): Oscar Biblarz, Jose Sinibaldi. "December 2006." Includes bibliographical references (p. 63). Also available in print.

Electric propulsion thrusters are considered to be candidates for microsatellites; ion engines are among the most scalable. Miniaturizing the ion engine will require novel concepts for the ionizer. MEMS, nanotechnology and other new technologies are expected to impact here. This thesis explores the use of these technologies to enable a new design for ion-thruster propellant ionization. An ideal approach, using expensive fabrication processes, is first described. This approach could prove to be a good method for testing and for the collection of precise data. A cost effective approach, on which our testing is based, is then discussed in detailed. After assembling a facility which uses existing vacuum systems and available instrumentation, we manufactured and tested miniature discharge geometries consisting of commercial 2â x2â copper-clad wafers. Three nominal insulator thicknessâ were used, 0.005,â 0.010â and 0.115.â The wafers were each drilled with 9 equal wholes of diameters 300, 400, and 500 m. A total of 12 wafers were tested (including 3 widths without wholes for a baseline) for the breakdown voltage as a function of argon pressure in the range of 10 to 1000 mTorr. Results indicate that argon breakdown may occur in the holes consistent with the classical Paschen curves.

Micro-satellites often require the adaptation of existing propulsion systems. Electric propulsion thrusters are perhaps the best candidates to meet these needs and ion engines are among the most scalable. Miniaturizing the ion engine will require novel concepts for the ionizer with perhaps novel propellants. MEMS, nanotechnology and other technological advances are expected to impact on new designs. Our work shows that the ionization of Argon, which is an alternate fuel to Xenon, can be achieved at low voltages by utilizing Micro-Structured Electrode (MSE) Arrays. Copper-clad sheets separated by a dielectric material (fiberglass laminate epoxy resin system combined with a glass fabric substrate) of varying thickness (0.1 mm to 0.4 mm) form the discharge electrodes in the MSE arrays The wafers are drilled with an array of holes and this geometry serves to concentrate the electric field between electrodes enhancing electron emission at the cathode. Minimum breakdown voltages between 240 and 280 Volts at pressures of around 100 mTorr (0.133N/m2) were consistently obtained with arrays of hole diameter ranging from 300 to 500um. These results are consistent with conventional Paschen-curves with two empirical constants that arise from our unconventional geometrical arrangements and from the different material properties.

Thesis (M.S. in Astronautical Engineering)--Naval Postgraduate School, June 1990. / Thesis Advisor(s): Agrawal, Brij N. Second Reader: Biblarz, Oscar. "June 2009." Description based on title screen as viewed on 19 October 2009. DTIC Identifier(s): Ion propulsion, synchronous satellites, NSSK (North South Station Keeping). Author(s) subject terms: Ion propulsion, geosynchronous satellite, North-South Station Keeping. Includes bibliographical references (p. 153-156). Also available in print.

Poon, Ho Shing. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (leaves 66-69). / Abstracts in English and Chinese. / ACKNOWLEDGEMENTS --- p.III / TABLE OF CONTENTS --- p.IV / TABLE OF FIGURES --- p.VI / LIST OF TABLES --- p.IX / Chapter CHAPTER 1: --- INTRODUCTION --- p.1 / Chapter 1.1 --- Intrinsic Problem of Conventional Aerodynamic Flying Devices --- p.1 / Chapter 1.2 --- Novel Ionic Propulsion Technology - Ionic Flyer --- p.2 / Chapter 1.3 --- Historical Development and Related Work of Ionic Flyer --- p.2 / Chapter 1.4 --- Existing Results in Our Group --- p.3 / Chapter 1.5 --- Objective and Current Achievements --- p.4 / Chapter 1.6 --- Organization of the remaining thesis --- p.5 / Chapter CHAPTER 2: --- FUNDAMENTAL KNOWLEDGE OF IONIC FLYERS --- p.6 / Chapter 2.1 --- Basic structure of Ionic Flyers --- p.6 / Chapter 2.2 --- Working Principle of Ionic Flyers --- p.7 / Chapter 2.3 --- Parametric models of the Ionic Flyers --- p.8 / Chapter 2.3.1 --- Electrical Current-Voltage Model --- p.8 / Chapter 2.3.2 --- Mechanical Lift-Force Model --- p.9 / Chapter CHAPTER 3: --- STRUCTURAL ANALYSIS OF IONIC FLYERS --- p.11 / Chapter 3.l --- Analysis on the Electrode Length --- p.11 / Chapter 3.2 --- Analysis on the Emitter radius --- p.12 / Chapter 3.3 --- Analysis on the Gap Distance between Emitter and Collector --- p.13 / Chapter 3.4 --- Analyses on the Emitter-Collector Electrodes Configuration --- p.15 / Chapter 3.4.1 --- Single-Emitter-Single-Collector Wire-Plate Configuration --- p.15 / Chapter 3.4.2 --- Multiple-Emitter-Single-Collector Wire-Plate Configuration --- p.16 / Chapter 3.4.3 --- Single-Emitter-Multiple-Collector Wire-Plate Configuration --- p.17 / Chapter 3.4.4 --- Single-Emitter-Surface-Collector Wire-Plate Configuration --- p.19 / Chapter 3.5 --- Summary - Optimization Design Methodology --- p.21 / Chapter CHAPTER 4: --- HIGH VOLTAGE POWER GENERATION SYSTEM --- p.22 / Chapter 4.1 --- Existing Marketable High Voltage Power Supplies --- p.22 / Chapter 4.2 --- design of the High Voltage Power Supply --- p.24 / Chapter 4.2.1 --- Battery --- p.25 / Chapter 4.2.2 --- Step-up Transformer --- p.25 / Chapter 4.2.3 --- Voltage Multiplier --- p.26 / Chapter 4.2.4 --- Driving Circuit --- p.27 / Chapter 4.3 --- Testing prototypes --- p.28 / Chapter 4.3.1 --- First Prototype --- p.28 / Chapter 4.3.2 --- Second Prototype --- p.29 / Chapter 4.3.3 --- Third Prototype --- p.30 / Chapter 4.3.4 --- Fourth Prototype --- p.31 / Chapter 4.3.5 --- Comparison of the Four Prototypes --- p.32 / Chapter 4.4 --- Performance of the High Voltage Power Supply --- p.34 / Chapter 4.4.1 --- Vary with Frequency --- p.34 / Chapter 4.4.2 --- Vary with Duty Cycle --- p.34 / Chapter 4.4.3 --- Efficiency --- p.35 / Chapter 4.5 --- Resonance Frequency Tracking Algorithm --- p.36 / Chapter 4.5.1 --- Fixed Frequency --- p.37 / Chapter 4.5.2 --- Scan Through a Frequency Range --- p.37 / Chapter 4.5.3 --- Continuous Comparison of Feedback Voltages --- p.38 / Chapter 4.5.4 --- Comparison of the Three Approaches --- p.40 / Chapter 4.6 --- Possibility Analysis on Self-Sufficient On-board Power Supply --- p.41 / Chapter 4.6.1 --- Analysis Based on the Parametric models --- p.41 / Chapter 4.6.2 --- Proposed Solution - Ionic Propulsion Blimp --- p.43 / Chapter CHAPTER 5: --- DEVELOPMENT OF IONIC PROPULSION BLIMP --- p.44 / Chapter 5.l --- Design and Structure of Ionic Propulsion Blimp --- p.44 / Chapter 5.1.1 --- Required Volume of the Blimp --- p.45 / Chapter 5.1.2 --- Initial Experimental results of Ionic Propulsion Blimp --- p.46 / Chapter 5.2 --- Advanced Navigation System for Ionic Propulsion Blimp --- p.47 / Chapter 5.2.1 --- Direction Control System --- p.47 / Chapter 5.2.2 --- Vision-Based Sensing and Control System --- p.48 / Chapter 5.3 --- Experimental results of the Advanced Navigation System --- p.55 / Chapter 5.3.1 --- Manual Control for Directional Movement --- p.55 / Chapter 5.3.2 --- Object Tracking using L-K Feature Tracking method --- p.56 / Chapter 5.3.3 --- Object Tracking using CamShift method --- p.57 / Chapter 5.3.4 --- Short summary for Vision-Based Control --- p.57 / Chapter CHAPTER 6: --- FURTHER DEVELOPMENT --- p.58 / Chapter 6.1 --- Improvement on Fabrication of Ionic Flyer --- p.58 / Chapter 6.2 --- Feasibility study on decreasing the operation voltage by minimizing the Gap Distance --- p.59 / Chapter 6.3 --- Improvement of the Design of Ionic Propulsion Blimp --- p.60 / Chapter 6.3.1 --- Design of Configuration of the Navigation System --- p.60 / Chapter 6.3.2 --- Design of the Ionic Flyer --- p.60 / Chapter 6.4 --- Commercialization Issue --- p.61 / Chapter 6.4.1 --- Safety Concerns --- p.61 / Chapter 6.4.2 --- Potential Application of Ionic Propulsion Technology --- p.63 / Chapter CHAPTER 7: --- CONCLUSION --- p.64 / BIBLIOGRAPHY --- p.66 / PUBLICATIONS --- p.69

Thesis (Ph. D.)--Ohio State University, 2007. / Title from first page of PDF file. Includes bibliographical references (p. 232-236).

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