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Recent Publications and Patents by the Aerospace Technical Staff

Publications and Papers

(June 2004–December 2004)

R. E. Anderson, D. D. Sawall, A. R. Hopkins, and R. M. Villahermosa, "Electrochemical Synthesis of Polyaniline Nanofibers," Polymer Preprints, Vol. 45, No. 1, pp. 230–231 (2004).

K. Baker, "A New Power Conversion System, Heat Engine and Space Power System for Earth Orbit Applications," 2nd International Energy Conversion Engineering Conference (Providence, RI, Aug. 16–19, 2004), AIAA Paper 2004-5695.

K. Baker, "A New Space Power Concept for Space Exploration," Space 2004 Conference and Exhibit (San Diego, CA, Sept. 28–30, 2004), AIAA Paper 2004-6105.

M. A. Bautista, R. J. Rudy, and C. C. Venturini, "The Importance of Collisional Coupling Among High-Energy Pseudometastable Levels of Fell Excited by Ly Omega," Astrophysical Journal, Vol. 604, pp. L129–132 (Apr. 1, 2004).

James L. Benjamin et al., "Risk Chair for Concurrent Design Engineering: Satellite Swarm Illustration," Journal of Spacecraft and Rockets, Vol. 41, No.1, pp. 51–59 (2004).

P. A. Bertrand, "Effects of Aryl Phosphate Ester Lubricant Additives on Crack Growth in Soda-Lime Glass," Tribology Letters, Vol. 16, No. 3, pp. 201–205 (2004).

J. B. Blake et al., "Quantification of Relativistic Electron Microburst Losses During the GEM Storms," Geophysical Research Letters, Vol. 31, No. 4, p. L04802 (Feb. 19, 2004).

I. D. Boyd and M. W. Crofton, "Modeling the Plasma Plume of a Hollow Cathode," Journal of Applied Physics, Vol. 95, No. 7, pp. 3285–3296 (Apr. 1, 2004).

J. C. Camparo, "Spatial Partitioning of the Molecular Wave Function: Reexamination of the Bond-Charge Model of Covalent Binding," International Journal of Quantum Chemistry, Vol. 100, pp. 41–52 (2004).

J. C. Camparo, S. C. Moss, and S. LaLumondiere, "Space-System Timekeeping in the Presence of Solar Flares," IEEE Aerospace and Electronic Systems Magazine, Vol. 19, No. 5, pp. 3–8 (May 2004).

L. A. Campbell, "On a Paper of Lang and Masiamani," Journal of Pure and Applied Algebra, Vol. 190, pp. 23–30 (2004).

K. Chan, "Short-Term vs. Long-Term Spacecraft Encounters," AIAA/AAS Astrodynamics Specialist Conference and Exhibit (Providence, RI, Aug. 16–19, 2004), AIAA Paper 2004-5460.

J. Clemmons, J. Hecht, et al., "Analysis of High-Altitude Ionization Gauge Measurements Using the Direct Simulation Monte Carlo Method," 37th AIAA Thermophysics Conference (Portland, OR, June 28–July 1, 2004), AIAA Paper 2004-2686.

M. Crofton, "NEXIS Cathode Measurements at the Species Level," 40th AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit (Ft. Lauderdale, FL, July 11–14, 2004), AIAA Paper 2004-4224.

P. A. Dafesh, P. Hanson, R. Yowell, et al., "A Portable UWB to GPS Emission Simulator," Position Location and Navigation Symposium (Apr. 26–29, 2004), pp. 405–413.

K. Diamant, J. Pollard, R. Cohen, et al., "Investigation of a Segmented Electrode Hall Thruster," 40th AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit (Ft. Lauderdale, FL, July 11–14, 2004), AIAA Paper 2004-4098.

K. Dotson and B. Sako, "An Investigation of Propulsion-Structure Interaction in Solid Rocket Motors," 40th AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit (Ft. Lauderdale, FL, July 11–14, 2004), AIAA Paper 2004-4183.

K. Dotson, B. Sako, et al., "Effects of Unsteady Pump Cavitation on Propulsion-Structure Interaction (Pogo) in Liquid Rockets," 45th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference (Palm Springs, CA, Apr. 19–22, 2004), AIAA Paper 2004-2027.

K. W. Dotson and W. A. Engblom, "Vortex-Induced Vibration of a Heavy-Lift Launch Vehicle During Transonic Flight," Journal of Fluids and Structures, Vol. 19, pp. 669–680 (2004).

R. K. Douglas et al., "Linear System Input-order Reduction by Hankel Norm Maximization," Journal of Guidance, Control, and Dynamics, Vol. 27, No. 1, pp. 150–154 (Jan. 2004).

R. B. Dybdal, "Polarization Limitations in Antenna Tracking," Antennas and Propagation Society Symposium, IEEE, Vol. 3, pp. 3240–3252 (June 20–25, 2004).

R. B. Dybdal and D. D. Pidhayny, "Main Beam Alignment Verification," Antennas and Propagation Society Symposium, IEEE, Vol. 3, pp. 3253–3256 (June 20–25, 2004).

W. Engblom et al., "Computation of Transverse Injection into Supersonic Crossflow with Various Injector Orifice Geometries," 42nd AIAA Aerospace Sciences Meeting and Exhibit (Reno, NV, Jan. 5–8, 2004), AIAA Paper 2004-1199.

J. A. Gelbwachs and R. Farley, "GLITTER: New Lidar Technique for Cloud-Base Altimetry—Description and Initial Aircraft Measurements," Applied Optics, Vol. 43, No. 14, pp. 2957–2961 (May 10, 2004).

J. George, R. Koga, et al., "Heavy Ion SEE Testing of Xilinx One-time Programmable Configuration PROMs," Radiation Effects Data Workshop, IEEE (July 22, 2004), pp. 72–78.

V. Goyal and J. Klug, "Interphasic Formulation for the Prediction of Delamination," 45th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference (Palm Springs, CA, Apr. 19–22, 2004), AIAA Paper 2004-1845.

J. Granata et al., "AFRL Thin Film Solar Cell Development and Upcoming Flight Experiments," 2nd International Energy Conversion Engineering Conference (Providence, RI, Aug. 16–19, 2004), AIAA Paper 2004-5734.

R. S. Groom et al., "Overview of the Development of Dynamic Environments for Atlas V Launch Vehicles," Journal of Spacecraft and Rockets, Vol. 41, No. 5, pp. 779–786 (2004).

G. F. Hawkins, A. J. Majamaki, R. P. Welle, B. S. Hardy, and J. W. Murdock, "A Novel Variable-Area Nozzle," 52nd JANNAF Propulsion Meeting Proceedings (Las Vegas, NV, May 10–13, 2004).

J. H. Hecht, R. L. Bishop, J. H. Clemmons, R. L. Walterscheid, et al., "An Overview of Observations of Unstable Layers During the Turbulent Oxygen Mixing Experiment (TOMEX)," Journal of Geophysical Research, Vol. 109, p. D02S01 (Jan. 21, 2004).

R. Hopkins, S. Hast, H. Karrenberg, J. Miyamoto, T. Lang, et al., "The BSpace Algorithm—A Statistical Model of Satellite Constellation Performance," AIAA Modeling and Simulation Technologies Conference and Exhibit (Providence, RI, Aug. 16–19, 2004), AIAA Paper 2004-4793.

A. Jenkin, "Representative Mission Trade Studies for Low-Thrust Transfers to Geosynchronous Orbit," AIAA/AAS Astrodynamics Specialist Conference and Exhibit (Providence, RI, Aug. 16–19, 2004), AIAA Paper 2004-5086.

A. B. Jenkin, "Effect of Orbit Data Quality on the Feasibility of Collision Risk Management," Journal of Spacecraft and Rockets, Vol. 41, No. 4, pp. 677–683 (July 2004).

D. Kalitan, M. Rickard, et al., "A Shock-Tube Study of the Oxidation of C₂H₆/O₂/AR and C₂H₆/SiH₄/O₂/AR Mixtures," 40th AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit (Ft. Lauderdale, FL, July 11–14, 2004), AIAA Paper 2004-3370.

L. E. Kirkland, K. C. Herr, and P. M. Adams, "Contrasting Interpretations of TES Spectra of the 2003 Rover 'Opportunity' Landing Site: Hematite Coatings and Grey Hematite," Lunar and Planetary Science Conference XXXV (Houston, TX, Mar. 15–19, 2004).

L. E. Kirkland, K. C. Herr, and P. M. Adams, "A Different Perspective for the Mars Rover 'Opportunity' Site: Fine-Grained, Consolidated Hematite and Hematite Coatings," Geophysical Research Letters, Vol. 31, p. L05704 (Mar. 12, 2004).

L. E. Kirkland, K. C. Herr, P. M. Adams, E. R. Keim, et al., "Mars-Lab: First Remote Sensing Data of Mineralogy Exposed at Small Mars-Analog Craters, Nevada Test Site," Lunar and Planetary Science Conference XXXV (Houston, TX, Mar. 15–19, 2004).

R. Koga, V. Tran, J. George, K. Crawford, S. Crain, M. Zakrzewski, and P. Yu, "SEE Sensitivities of Selected Advanced Flash and First-in-First-Out Memories," Radiation Effects Data Workshop, IEEE (July 22, 2004), pp. 47–53.

R. Kumar, "Performance of an Incoherent Receiver for the Command Destruct Signals of the Space Lift Range System," 22nd AIAA International Communications Satellite Systems Conference and Exhibit (Monterey, CA, May 9–12, 2004), AIAA Paper 2004-3107.

R. Kumar, "Phase Noise Analysis in the Presence of Spurious Signals," 22nd AIAA International Communications Satellite Systems Conference and Exhibit (Monterey, CA, May 9–12, 2004), AIAA Paper 2004-3229.

R. Kumar and R. Martinez, "CDMA Satellite System Capacity with Multiple User Classes," 22nd AIAA International Communications Satellite Systems Conference and Exhibit (Monterey, CA, May 9–12, 2004), AIAA Paper 2004-3131.

R. Kumar and D. Taggart, "Analog-to-Digital Converters Load Factor Analysis for Wideband Communication Satellite Systems," 22nd AIAA International Communications Satellite Systems Conference and Exhibit (Monterey, CA, May 9–12, 2004), AIAA Paper 2004-3175.

R. Kumar, D. Taggart, and G. Goo, "Performance of the MPSK and QAM Modulation Schemes in the Presence of Narrowband Interference," 22nd AIAA International Communications Satellite Systems Conference and Exhibit (Monterey, CA, May 9–12, 2004), AIAA Paper 2004-3245.

S. Lim, "Analytic Framework for Flexible Transponder Return on Investment," 22nd AIAA International Communications Satellite Systems Conference and Exhibit (Monterey, CA, May 9–12, 2004), AIAA Paper 2004-3102.

S. Liu, E. Simburger, D. Hinkley, J. Coggi, D. Rumsey, and J. Matsumoto, "Pico-Satellite Inflatable Reflector Experiment (PSIREX) Pico-Satellite Power System," 2nd International Energy Conversion Engineering Conference (Providence, RI, Aug. 16–19, 2004), AIAA Paper 2004-5687.

T. S. Lomheim, E. A. Nussbaumer, J. A. Lang, D. W. Warren, and N. Caraballo, "Parametric Methodologies and Tools for First-Order Hyperspectral Imaging Sensor System Design," Imaging Spectrometry X (Denver, CO, Aug. 2–4, 2004), SPIE, Vol. 5546, pp. 1–28.

D. K. Lynch, R. J. Rudy, S. Mazuk, C. C. Venturini, R. C. Puetter, and R. B. Perry, "V445 Puppis," International Astronomical Union Circular, No. 8278, p. 1 (Jan. 29, 2004).

J. E. Mazur et al., "Abundances of Heavy and Ultraheavy Ions in 3He-Rich Solar Flares," Astrophysical Journal, Vol. 606, pp. 555–564 (May 1, 2004).

M. Panevsky, "Characterization of the Resonant Electromagnetic Mode in Helicon Discharges," Physics of Plasmas, Vol. 11, No. 9, pp. 4196–4205 (Sept. 2004).

R. P. Patera, "Application of Symmetrized Covariances in Space Confliction Prediction," Advances in Space Research, Vol. 34, pp. 1115–1119 (2004).

R. P. Patera, "Conventional Form of the Collision Probability Integral for Arbitrary Space Vehicle Shape," AIAA/AAS Astrodynamics Specialist Conference and Exhibit (Providence, RI, Aug. 16–19, 2004), AIAA Paper 2004-5218.

R. P. Patera, "Managing Risk for Space Object Reentry," Fifth National Symposium, Space Systems Engineering and Risk Management (The Aerospace Corporation, El Segundo, CA, Feb. 2004).

R. P. Patera, "Parameter Relations in Orbital Collision Risk," 55th International Astronomical Congress (Vancouver, Canada, Oct. 4–8, 2004).

R. G. Pettit IV et al., "Modeling Behavioral Patterns of Concurrent Software Architectures Using Petri Nets," Software Architecture 2004, WICSA 2004, Fourth Working IEEE/IFIP Conference (June 12–15, 2004), pp. 57–66.

D. E. Ping and R. B. Dybdal, "An Efficient Dual Frequency Antenna Feed," Antennas and Propagation Society Symposium, IEEE, Vol. 3, pp. 3135–3138 (June 20–25, 2004).

D. E. Ping, J. T. Shaffer, L. U. Brown, and R. B. Dybdal, "A Broadband Rolled Edged Cavity Antenna," Antennas and Propagation Society Symposium, IEEE, Vol. 1, pp. 787–790 (June 20–25, 2004).

G. Radhakrishnan, R. E. Robertson, P. M. Adams, S. S. Osofsky, and K. S. MacGowan, "Fabrication and RF Properties of Titanium Carbide/Gold Coplanar Waveguides for RF MEMS Applications," Materials Research Society Symposium, Vol. 782, pp. 429–434 (2004).

S. Raghavan, K. Tsai, and L. Cooper, "GPS CDMA Noise Analysis," 22nd AIAA International Communications Satellite Systems Conference and Exhibit (Monterey, CA, May 9–12, 2004), AIAA Paper 2004-3182.

S. Rubin, "An Interpretation of Transfer Function Data for a Cavitating Pump," AIAA/ASME/SAE/ASEE 40th Joint Propulsion Conference and Exhibit (Ft. Lauderdale, FL, July 11–14, 2004), AIAA Paper 2004-4025.

R. J. Rudy, D. K. Lynch, S. M. Mazuk, C. C. Venturini, et al., "Properties of Galactic B[e] Supergiants. III. MWC 300," Astronomy and Astrophysics, Vol. 417, pp. 731–743 (2004).

B. Sako and A. Kabe, "A Direct Least Square Formulation of the KMA Method," 45th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference (Palm Springs, CA, Apr. 19–22, 2004), AIAA Paper 2004-1531.

R. S. Selesnick, "Radiation Belt Electron Dynamics: Modeling Atmospheric Losses," NASA Report No. RECON 20040006299.

G. A. Sefler, G. C. Valley, et al., "Secondary Energy Transfer and Nonparticipatory Yb3+ Ions in Er3+ - Yb3+ High-Power Amplifier Fibers," Journal of the Optical Society of America B, Vol. 21, No. 10, pp. 1740–1748 (Oct. 2004).

E. Simburger, J. Matsumoto, T. Giants, A. Garcia, S. Liu, et al., "Engineering Development Model Testing of the PowerSphere," 45th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference (Palm Springs, CA, Apr. 19–22, 2004), AIAA Paper 2004-1570.

K. Siri and C. Truong, "Frequency Response Analysis for Power Conversion Products Without Small-Signal Linearization," IEEE Aerospace Conference, Proceedings, Vol. 6, pp. 4026–4033 (Mar. 6–13, 2004).

C. C. Venturini, R. J. Rudy, D. K. Lynch, and S. Mazuk, "Near-Infrared Spectroscopy of V1493 Aquilae and V4642 Saqittarll: Two Novae with Unusual Spectral Features," Astronomical Journal, Vol. 128, pp. 405–410 (July 2004).

C. Wang et al., "Retrospective and Recent Examples of Aircraft Parameter Identification at NASA Dryden Flight Research Center," Journal of Aircraft, Vol. 41, No. 4, pp. 752–764 (July 2004).

W. Yeung and T. Lam, "A Numerical Scheme for Solving Two-Dimensional Thermal Propagation in Composites," 37th AIAA Thermophysics Conference (Portland, OR, June 28–July 1, 2004), AIAA Paper 2004-4025.

P. Zomkowski, J. Maksymowicz, and K. Conner, "Test Bed for Analyzing High Frame-Rate Detector Devices with Reprogrammable Capabilities," AIAA Guidance, Navigation, and Control Conference and Exhibit (Providence, RI, Aug. 16–19, 2004), AIAA Paper 2004-5124.

Patents

R. B. Dybdal, "Orthogonal Polarization and Frequency Selectable Waveguide Using Rotatable Waveguide Sections," U.S. Patent No. 6,816,026, Nov. 2004.

This waveguide device permits the selection of either linearly or circularly polarized signals in user terminals for commercial satellite systems. This capability allows a single terminal design to be interchangeably used for different satellite services. The ability to sequentially use different satellite services with a common terminal design avoids the cost of purchasing multiple terminals for each service. The waveguide design has low insertion loss for efficient operation and a high power-handling capability in comparison with conventional hybrid and switch combiners. Furthermore, the switch devices can be cascaded with appropriate waveguide transitions for simultaneous multiple frequency operation, for example, C- and Ku-band frequency commercial services.

G. F. Hawkins, J. W. Murdock, "Composite Damping Material," U.S. Patent No. 6,830,793, Dec. 2004.

Fluid-filled three-dimensional bodies or "machines" embedded in a polymeric matrix provide damping of vibroacoustic forces. The machines have an internal space that changes volume when the composite material is subjected to a predetermined force. The space is filled by a viscous and compression-resistant fluid that flows in or out in response to the volume changes. The fluid can also include bubbles of compressible fluid. The bubbles would act as a reservoir, expanding or contracting as the volume of the internal space changes. Arrays of long tubular or cylindrical bodies can be arranged in planes to achieve varying dampening profiles.

D. A. Hinkley, E. J. Simburger, "Conductive Shape Memory Metal Deployment Latch Hinge," U.S. Patent No. 6,772,479, Aug. 2004.

Designed for use with microsatellites, a conductive hinge made of a shape-memory alloy can be used for stowing and deploying solar panels. In its basic form, the hinge is made from a thin sheet of superelastic material such as nitinol (NiTi) that can be bent around an extremely small radius without breakage or permanent deformation. The hinge is used to connect thin-film solar-cell panels, which can be stacked on top of each other with minimal spacing. On orbit, the solar array is released and deployed (by the elastic energy stored in the hinge material) into a predetermined shape such as a PowerBox or PowerSphere. The hinge can be further adapted into a latch to lock the panels in place after deployment. Also, because the material is electrically conductive, the hinge can function as a power bus for routing current through multiple interconnected panels.

J. P. Hurrell, D. A. Kozlowski, "Optical Fiber Quadrature Demodulator," U.S. Patent No. 6,778,317, Aug. 2004.

A quadrature demodulator for use in optical receivers mitigates the problem of phase shifting that can occur when portions of a signal are sent through separate optical fibers. The demodulator has an optical local oscillator that generates a weak pilot tone that is mixed with the large optical input signal. Thus, the pilot tone and input signal are exposed to the same environmental perturbations of the optical fibers. The pilot tone functions as a phase-shift reference, enabling the demodulator to maintain optical phase coherence between the separate in-phase (I) and quadrature (Q) optical channels. During homodyne demodulation, the pilot tone is routed through I- and Q-channel fibers and then mixed with the optical local oscillator to produce the error component for closed-loop control. The detected quadrature components of the unknown input signal can be used for coherent or incoherent optical receiver applications.

S. W. Janson, H. Helvajian, "Integrated Glass Ceramic Spacecraft," U.S. Patent No. 6,830,221, Dec. 2004.

Photostructurable glass-ceramic materials can be used to make spacecraft support structures, insulated circuit substrates, multichip module supports, actuators, sensors, and thermal control systems. The materials can be inexpensively molded into any shape, machined to micron tolerances, metalized to form electronic structures, and assembled through fusion bonding. When tempered, the materials resist tension-induced fracture and function as electrical and thermal insulators; they are also transparent to visible and near-infrared light. The photostructurable glass-ceramic materials do not outgas chemicals, have zero porosity, can be handled using cleanroom protocols, and are amenable to system integration using standard microelectronics fabrication techniques. This multifunctionality allows almost an entire integrated spacecraft to be fabricated from these materials.

F. E. Livingston, H. Helvajian, "Photosensitive Glass Variable Laser Exposure Patterning Method," U.S. Patent No. 6,783,920, Aug. 2004.

This microfabrication technique can be used to form features of high and low aspect ratio in a photosensitive material such as photostructurable glass. The key to this technique corresponds to the fine control of the material exposure dose by a variable-intensity pulsed ultraviolet laser during direct-write patterning. The consequence is that differing etch rates can be achieved across the substrate without the need for protective etch masks. The method offers direct-write serial patterning with batch chemical processing and permits the fabrication of complex structures and features on a single wafer. Adjacent microstructures with aspect ratios ranging from 2:1 to 30:1 can be created. The variable exposure method enables the conversion of computer-assisted design patterns and corresponding laser irradiance information into microfabricated structures that retain precise feature sizes within predetermined dimensions. The method can be used in the fabrication of high-aspect-ratio mesoscale structures that require fine microscale features, for example, in complex fluidic devices or in far-infrared or terahertz devices.

G. L. Lui, K. Tsai, "Data Aided Carrier Phase Tracking System for Precoded Continuous Phase Modulated Signals," U.S. Patent No. 6,771,713, Aug. 2004.

Data-aided synchronizers are used to track the symbol timing and carrier phase of a continuous phase modulation (CPM) signal in the presence of noise. These digital synchronizers are suitable for use in Gaussian minimum shift keying (GMSK) communications systems. Data-aided tracking is applied in two forms. In the first, the timing error of the received CPM signal is extracted from the principal Laurent amplitude modulation component by an early and late gating operation, followed by a multiplication of the data decision, which removes the data modulation in the error signal. In the second form, the phase error of the received CPM signal is extracted by a cross-correlation operation, with the data decision produced by a serial data demodulator. In each case, the resulting error signal is tracked by a second-order digital loop operating at the symbol rate.

T. M. Nguyen, J. K. Holmes, "Mobile Surface Terminal Communication System," U.S. Patent No. 6,804,493, Oct. 2004.

Using code-division multiple-access (CDMA) protocols, this networked communication system can transmit command and telemetry data between a spacecraft orbiting a planet and a number of mobile landers or rovers on the planet's surface. When several landers come within the beamwidth of the spacecraft antenna, they can all receive communication simultaneously. The downlink transmitter has a quadrature component that carries a pilot code for coarse acquisition and an in-phase component that carries a Walsh-Hadamard code and a PN code for fine acquisition. The downlink subsystem uses direct-sequence spread-spectrum signaling and amplitude modulation. The uplink subsystem uses spread-spectrum signaling and phase modulation. Characterized by reduced mass, size, and power consumption, the system provides reliable operation despite fading and multipath effects caused by variable surface terrain and atmospheric interference.

R. P. Patera, "Vehicular Trajectory Collision Conflict Prediction Method," U.S. Patent No. 6,820,006, Nov. 2004.

To reduce the risk of a spacecraft or aircraft colliding with another object, this method first screens out objects that present no risk. For those that could possibly collide, the method then determines whether the distance between the two objects at their closest approach will be less than a critical amount. If so, conjunction determinations are performed using high-fidelity time-stepped trajectory propagation. When conjunction is indicated, the method then determines the collision probability based on an error covariance matrix that is transformed to an encounter frame by rotation and scaling. A contour integration method can then efficiently compute collision conflict probability. When the probability exceeds a certain threshold, the method determines an avoidance maneuver, optimized in terms of direction, magnitude, and time. For each value of time before anticipated conjunction, a gradient method determines the optimal direction, and a numerical search method determines the optimal magnitude.

K. Siri, "Dynamic DC Source and Load Energy Recycling Power System," U.S. Patent No. 6,775,160, Aug. 2004.

Designed for economical testing of DC-to-DC power converters and similar electronic devices, this system provides direct testing power to a system under test at a significant level above the net input power drawn from the utility grid or the input power source. The system uses at least an efficient DC-DC converter serving as a controllable electronic load that absorbs the output power from the system under test and feeds it back into the main input, rather than flushing it out to the power grid or letting it fully dissipate as heat, as occurs in conventional electronic loads. Stability can be improved by means of transient stabilizers inserted in the feedback path. Undervoltage and overvoltage limiters can be included for additional stability and reliability, and an active power-factor correction AC-to-DC converter can be inserted to improve power quality and efficiency of power transferred from the utility grid.

E. J. Simburger, "Inflatable Gas Cell Structure Deploying Method," U.S. Patent No. 6,817,176, Nov. 2004.

This patent describes a method and system for sequentially inflating the cells in an inflatable structure by means of electronic control and power lines integrated into the walls of each cell. A microelectromechanical system (MEMS) capable of generating inflation gas is placed inside each cell. The MEMS contains all of the associated electronics for controlling the release of gas in small increments and determining the resultant pressure change in the inflatable structure. The control electronics can execute a preprogrammed inflation sequence and communicate status along with any measured parameters to a central processor. The MEMS devices would operate using direct current and control lines supplied from a spacecraft bus. Various types of gas generators can be used, such as cellular containment evaporation gas generators and laser ablation gas generators.

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