Bookmarks

Recent Publications and Patents by the Aerospace Technical Staff

Publications

M. J. Baxter, "Empirical Investigation of Three Approaches to Design Modeling," IEEE Aerospace Conference, Vol. 8 (Mar. 8–15, 2003), pp. 8-3801–8-3814.

J. C. Chai, E. Dressel, A. O. Britting, and J. L. Montegut, "Electromagnetic Pickups by Long Heliax Cables in Lightning Environments," IEEE International Symposium on Electromagnetic Compatibility, Vol. 1, pp. 286–291 (Aug. 18–22, 2003).

J. C. Chai, S. Y. Feng, E. Dressel, and J. L. Montegut, "Empirical Correlations Between OLMS and CGLSS Lightning Data," IEEE International Symposium on Electromagnetic Compatibility, Vol. 2, pp. 489–494 (Aug. 18–22, 2003).

D. J. Chang, "Burst Tests of Filament-Wound Graphite-Epoxy Tubes," Journal of Composite Materials, Vol. 37, No. 9, pp. 811–829 (2003).

D-W. Chen, "CW Tunable Midwave Infrared Generation Near 4.5 µm," OSA Tops Advanced Solid-State Photonics, Vol. 83, pp. 320–326 (July 1, 2003).

D-W. Chen, "Continuous-Wave Tunable Midwave Infrared Generation near 4.5 µm with an Intracavity Optical Parametric Oscillator and Difference Frequency Generation," Journal of the Optical Society of America B (Optical Physics), Vol. 20, No. 7, pp. 1527–1531 (July 2003).

J. C. Chen, C. C. Wang, D. Taggart, and E. Ditata, "Modeling an Off-Nominal Launch Vehicle Trajectory for Range Safety Link Analysis," IEEE Aerospace Conference, Vol. 7 (Mar. 8–15, 2003), pp. 3419–3426.

B. N. Chhouk and A. O. Lopez, "Performance Analysis of the Super*Zip Separation System," 39th AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit (Huntsville, AL, July 20–23, 2003), AIAA Paper 2003-4529.

M. Clifford, D. Faigin, M. Bishop, and T. Brutch, "Miracle Cures and Toner Cartridges: Finding Solutions to the Spam Problem," 19th Annual Computer Security Applications Conference, Proceedings (Dec. 8–12, 2003), pp. 428–429.

M. W. Crofton and I. B. Boyd, "The T6 Hollow Cathode—Measurements and Modeling," 34th Plasmadynamics and Lasers Conference (Orlando, FL, June 23–26, 2003), AIAA Paper 2003-4171.

M. W. Crofton, M. D. Worshum, and B. L. Zeigler, "Differential Scattering of Xe(+) on Xe Target," 39th AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit (Huntsville, AL, July 20–23, 2003), AIAA Paper 2003-4541.

M. I. Desai, G. M. Mason, J. R. Dwyer, J. E. Mazur, R. E. Gold, S. M. Krimigis, C. W. Smith, and R. M. Skoug, "Evidence For a Suprathermal Seed Population of Heavy Ions Accelerated by Interplanetary Shocks Near 1 AU," Astrophysical Journal, Vol. 588, pp. 1149–1162 (May 10, 2003).

J. D. DeSain, A. D. Ho, and C. A. Taatjes, "High-Resolution Diode Laser Absorption Spectroscopy of the O-H Stretch Overtone Band (2, 0, 0) from (0, 0, 0) of the HO2 radical," Journal of Molecular Spectroscopy, Vol. 219, No. 1, pp. 163–169 (May 2003).

K. D. Diamant, J. E. Pollard, R. B. Cohen, Y. Raitses, and N. J. Fisch, "Plume Characteristics of the PPPL Segmented Electrode Hall Thruster," 39th AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit (Huntsville, AL, July 20–23, 2003), AIAA Paper 2003-5159.

K. D. Diamant, B. L. Zeigler, and R. B. Cohen, "Tunable Microwave Electrothermal Thruster Performance on Water," 39th AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit (Huntsville, AL, July 20–23, 2003), AIAA Paper 2003-5150.

S. J. DiMaggio, Z. H. Duron, and G. Davis, "Approximate Modal Identification of Lightly Damped Highly Symmetric Bladed Disks," AIAA Journal, Vol. 28, No. 6, pp. 1105–1112 (June 2003).

W. Dimpfl, G. Light, and L. Bernstein, "Molecular Dynamics from Remote Observation of CO(a) from Space Shuttle Plumes," Space 2003 (Long Beach, CA, Sep. 23–25, 2003), AIAA Paper 2003-6204.

M. Donabedian, ed., Spacecraft Thermal Control Handbook, Volume II: Cryogenics (The Aerospace Press and AIAA, El Segundo, CA, 2004).

R. B. Dybdal and D. D. Pidhayny, "Polarization Optimization for Tracking Antennas," IEEE Antennas and Propagation Society International Symposium, Vol. 2, pp. 365–368 (June 22–27, 2003).

T. Eng and J. Han, "Performance Impacts and Granularity Sensitivity of Dynamic Resource Allocation on DAMA Networks," Space 2003 (Long Beach, CA, Sep. 23–25, 2003), AIAA Paper 2003-6230.

S. Fergason, A. Guardone, and B. Argrow, "Construction and Validation of a Dense Gas Shock Tube," Journal of Thermophysics and Heat Transfer, Vol. 17, No. 3, pp. 326–333 (July 2003).

J. Fisher, G. H. Fisher, and P. F. Hamel, "Training Effective Systems Engineers," IEEE Aerospace Conference, Vol. 8 (March 8–15, 2003), pp. 8-3907–8-3914.

B. E. Gardner, A Hoheb, and D. J. Evans, "Enhancing Continuing Learning Support Systems for Corporate Engineers and Scientists," IEEE Aerospace Conference, Vol. 8 (Mar. 8–15, 2003), pp. 8-3897–8-3906.

D. G. Gilmore, ed., Spacecraft Thermal Control Handbook, Volume I: Fundamental Technologies (The Aerospace Press and AIAA, El Segundo, CA, 2002).

L. F. Halle, M. J. Kramer, M. D. Scott, J. C. Heim, and L. S. Tatman, "Space Systems Acquisitions Today: Systems Modeling, Design and Development Improvements, Integrating the Concept Design Center (CDC) and the NRO Analysis Center (NAC)," IEEE Aerospace Conference, Vol. 8 (Mar. 8–15, 2003), pp. 8-3647–8-3656.

M. A. Hobson and R. H. Buenneke, "Concepts for Satellite Communications and Navigation Support to Homeland Security Missions," IEEE Aerospace Conference, Vol. 2 (Mar. 8–15, 2003), pp. 2-1149–2-1154.

J. K. Holmes and S. Raghavan, "Code Loop Mean Slip Time Comparison of NRZ and BOC Signals," IEEE Aerospace Conference, Vol. 4 (Mar. 8–15, 2003), pp. 4-1575–4-1588.

S. Janson, "Micro/Nanotechnology for Micro/Nano/Picosatellites," Space 2003 (Long Beach, CA, Sep. 23–25, 2003), AIAA Paper 2003-6269.

S. W. Janson, "Micro/Nanotechnology for the Satellite World," MEMS Components and Applications For Industry, Automobiles, Aerospace, & Communications II, Society of Photo-Optical Instrumentation Engineers (San Jose, CA, Jan. 28–29, 2003), pp. 95–106.

J. A. Kechichian, "Constrained Circularization in Elliptic Orbit Using Low Thrust with Shadowing Effect," Journal of Guidance, Control, and Dynamics (0731-5090), Vol. 26, No. 6, pp. 949–955 (Nov. 2003).

R. Kumar, D. Taggart, and C. Wang, "Performance Analysis of a Command Destruct Subsystem of the Spacelift Range System," IEEE Aerospace Conference, Vol. 3 (Mar. 8–15, 2003), pp. 3-1381–3-1388.

C. Landauer and K. L. Bellman, "Delaying Difficult Design Decisions," IEEE International Workshop on Soft Computing in Industrial Applications (Binghamton, NY, June 23–25, 2003), pp.33–38.

C. Landauer and K. L. Bellman, "Self-Modeling Systems Self-Adaptive Software: Applications," Second International Workshop, IWSAS 2002 Revised Papers (Lecture notes in Computer Science, Vol. 2614), pp. 238–256 (2003).

E. M. Landsbaum, "Erosive Burning Revisited," 39th AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit (Huntsville, AL, July 20–23, 2003), AIAA Paper 2003-4805.

J. Lankford, "Measuring System and Software Architecture Complexity," IEEE Aerospace Conference, Vol. 8 (Mar. 8–15, 2003), pp. 8-3849–8-3857.

C. J. Latta, "Acquisition Funding—A Dynamic Modeling Approach," Space 2003 (Long Beach, CA, Sep. 23–25, 2003), AIAA Paper 2003-6379.

C. A. Lee, E. Coe, B. S. Michel, J. Stepanek, I. Solis, J. M. Clark, and B. Davis, "Using Topology-Aware Communication Services in Grid Environments," 3rd IEEE/ACM International Symposium on Cluster Computing and the Grid, Proceedings (May 12–15, 2003), pp. 534–541.

G. Lui and K. Tsai, "Performance Comparison of Quaternary GMSK and Filtered QPSK Signals in FDMA Systems," Space 2003 (Long Beach, CA, Sep. 23–25, 2003), AIAA Paper 2003-6228.

G. Lui and K. Tsai, "A Soft Bit Metric Demodulator for Pre-coded Quaternary CPM Signals," Space 2003 (Long Beach, CA, Sep. 23–25, 2003), AIAA Paper 2003-6227.

J. H. Ly and K. Siri, "Frequency Response Analysis for DC-DC Converters Without Small-Signal Linearization," 18th IEEE Applied Power Electronics Conference (Miami Beach, FL, Feb. 9–13, 2003), Vol. 2, pp. 1008–1013.

E. Mahr and G. Richardson, "Development of the Small Satellite Cost Model (SSCM) Edition 2002," IEEE Aerospace Conference, Vol. 8 (Mar. 8–15, 2003), pp. 8-3831–8-3841.

M. W. Maier, "The Potential of Gravity Gradiometry as an ISR Technique," IEEE Aerospace Conference, Vol. 2 (Mar. 8–15, 2003), pp. 2-1167–2-1177.

K. P. Maine, P. Anderson, and J. Langer, "Crosslinks for the Next-Generation GPS," IEEE Aerospace Conference, Vol. 4 (Mar. 8–15, 2003), pp. 4-1589–4-1596.

A. A. Moulthrop, M. S. Muha, and C. P. Silva, "Minimizing Distortions in the Time-Domain Measurement of Microwave Communications Signals," 61st ARFTG Conference Digest (June 13, 2003), pp. 133–141.

H. H. Nguyen and T. M. Nguyen, "Power Spectral Analysis for Spectrum Packing Efficiency Evaluation," IEEE Aerospace Conference, Vol. 3 (Mar. 8–15, 2003), pp. 3-1221–3-1226.

H. H. Nguyen and T. M. Nguyen, "Power Spectral Analysis for Spectrum Packing Efficiency Evaluation," IEEE Wireless Communications and Networking, Vol. 2 (Mar. 16–20, 2003), pp. 741–745.

H. H. Nguyen, T. W. Nuteson, and G. S. Mitchell, "A Direct Band-Pass Implementation of Subspace-Based Techniques for Direction Finding and Digital Beamforming Applications," IEEE Wireless Communications and Networking, Vol. 1 (Mar. 16–20, 2003), pp. 431–434.

H. H. Nguyen and C. Pate, "A Ground Segment Architecture with Mentat SkyX Protocol over a Geosynchronous Satellite," IEEE Aerospace Conference, Vol. 3 (Mar. 8–15, 2003), pp. 3-1245–3-1251.

T. M. Nguyen, D. A. Taggart, C. C. Wang, R. Kumar, J. C. Chen, A. Mathur, Y. Y. Krikorian, J. M. Charroux, L. Cooper, T. Nguyen, S. K. Do, N. No, M. Shane, and E. Ditata, "Modeling and Simulation Tool for the Spacelift Range System," IEEE Aerospace Conference, Vol. 3 (Mar. 8–15, 2003), pp. 3-1389–3-1395.

T. M. Nguyen, J. Yoh, C. H. Lee, H. T. Tran, and D. M. Johnson, "Modeling of HPA and HPA Linearization Through a Predistorter: Global Broadcasting Service Applications," IEEE Transactions on Broadcasting, Vol. 49, No. 2, pp. 132–141 (June 2003).

M. J. O'Brien, N. Presser, and E. Y. Robinson, "Failure Analysis of Three Si₃N₄ Balls Used in Hybrid Bearings Engineering," Engineering Failure Analysis, Vol. 10, pp. 453–473 (Aug. 2003).

T. P. O'Brien and M. B. Moldwin, "Empirical Plasmapause Models from Magnetic Indices," Geophysical Research Letters, Vol. 30, No. 4, pp. 1-1–1-4 (Feb. 15, 2003).

R. Patera, "Satellite Collision Probability for Nonlinear Relative Motion," Journal of Guidance, Control, and Dynamics (0731-5090), Vol. 26, No. 5, pp. 728–733 (Sep. 2003).

E. L. Petersen, M. Rickard, and R. P. Welle, "High-Temperature Nonreacting Flowfields Generated by a Hypersonic Chemical-Laser Nozzle," Journal of Thermophysics and Heat Transfer, Vol. 17, No. 3, pp. 420–422 (July–Sep. 2003).

J. E. Pollard and K. D. Diamant, "Hall Thruster Plume Shield Wake Structure," 39th AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit (Huntsville, AL, July 20–23, 2003), AIAA Paper 2003-5018.

A. Quan, K. Knudtzon, S. Hayati, J. Basilico, G. Prier, A. Schuler, R. Abbott, and R. Duvall, "Atria: Cooperative Agent-Based Recovery in a Communications Network," IEEE Aerospace Conference, Vol. 6 (Mar. 8–15, 2003), pp. 6-2903–6-2914.

G. Radhakrishnan, R. E. Robertson, R. C. Cole, and P. M. Adams, "Hybrid Pulsed Laser Deposition and Si-Surface-Micromachining Process for Integrated TiC Coatings in Moving MEMS," Applied Physics A, pp. 175–184 (July 2003).

J. A. Roden, B. Archambeault, and R. D. Lyle, "Effect of Stitching Capacitor Distance for Critical Traces Crossing Split Reference Planes," IEEE International Symposium on Electromagnetic Compatibility, Vol. 2, pp. 703–707 (Aug. 18–22, 2003).

J. A. Roden and T. W. Nuteson, "Finite Antenna Array Analysis and Design Using the FDTD Technique and the CPML Absorbing Boundary Condition," IEEE Antennas and Propagation Society International Symposium, Vol. 3, pp. 776–779 (June 22–27, 2003).

R. J. Rudy, C. C. Venturini, D. K. Lynch, S. M. Mazuk, R. C. Puetter, and C. H. Perry, "0.8–2.5 Micron Reflectance Spectroscopy of Pluto," Astronomical Society of the Pacific, Vol. 115, pp. 484–489 (Apr. 2003).

E. J. Simburger, T. W. Giants, J. H. Matsumoto, A. Garcia III, J. K. Lin, J. R. Day, S. E. Scarborough, H. B. Curtis, T. Kerslake, and T. Peterson, "Development, Design, and Testing of Power Sphere Multifunctional Ultraviolet-Rigidizable Inflatable Structures," 44th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference (Norfolk, VA, Apr. 7–10, 2003), AIAA Paper 2003–1897.

K. Siri and K. A. Conner, "Independently Sourced Parallel-Connected Power Systems with Maximum Power Tracking," 18th IEEE Applied Power Electronics Conference (Miami Beach, FL, Feb. 9–13, 2003), Vol. 1, pp. 533–539.

B. Soltz and H. Chen, "Lessons Learned in Modeling and Analysis of Isogrid Structures," Space 2003 (Long Beach, CA, Sep. 23–25, 2003), AIAA Paper 2003-6357.

P. R. Straus, P. C. Anderson, and J. E. Danaher, "GPS Occultation Sensor Observations of Ionospheric Scintillation," Geophysical Research Letters, Vol. 30, No. 8 (Apr. 2003).

D. Taggart, F. Bayuk, D. Ping, J. Hant, and M. Marshall, "Usage of Commercial Satellite Systems for Homeland Security Communications," IEEE Aerospace Conference, Vol. 2 (Mar. 8–15, 2003), pp. 2-1155–2-1165.

D. Taggart, R. Kumar, and Y. Krikorian, "Communication Systems Modeling Techniques," IEEE Aerospace Conference, Vol. 8 (Mar. 8–15, 2003), pp. 8-3707–8-3717.

L. H. Thaller and A. H. Zimmerman, Nickel-Hydrogen Life Cycle Testing (The Aerospace Press and AIAA, El Segundo, CA, 2003).

L. H. Thaller, A. H. Zimmerman, and G. A. To, "Techniques to Improve the Usability of Nickel-Hydrogen Cells," Journal of Power Sources, Vol. 114, No. 2, pp. 309–319 (Mar. 12, 2003).

D. A. Thompson, R. L. Rogers, and J. H. Davis, "Temperature Compensation of Total Power Radiometers," IEEE Transactions on Microwave Theory and Techniques, Vol. 51, No. 10, pp. 2073–2078 (Oct. 2003).

W. Tsien, C. Finley, M. Mocio, and C. Olmedo, "Advancing Military-Relevant Space Technologies," Space 2003 (Long Beach, CA, Sep. 23–25, 2003), AIAA Paper 2003-6363.

R. L. Walterscheid and J. H. Hecht, "A Reexamination of Evanescent Acoustic-Gravity Waves: Special Properties and Aeronomical Significance," Journal of Geophysical Research. D. Atmospheres, Vol. 108, No. D11 (June 2003).

C. C. Wang, "Improved Metric for Binary Turbo Decoding Using M-ary PSK Signals," IEEE Wireless Communications and Networking, Vol. 1 (Mar. 16–20, 2003), pp. 711–714.

H. Wang and W. F. Buell, "Velocity-Tunable Magneto-Optical-Trap-Based Cold Cs Atomic Beam," Journal of the Optical Society of America B (Optical Physics), Vol. 20, No. 10, pp. 2025–2030 (Oct. 2003).

J. C. T. Wang, E. M. Landsbaum, A. B. Cozart, S. A. Frolik, and I. Lee, "Recent Progress in SRM Ignition Transient Modeling," 39th AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit (Huntsville, AL, July 20–23, 2003), AIAA Paper 2003-5115.

R. P. Welle, B. S. Hardy, J. W. Murdock, A. J. Majamaki, and G.F. Hawkins, "Separation Instabilities in Over Expanded Nozzles," 39th AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit (Huntsville, AL, July 20–23, 2003), AIAA Paper 2003-5239.

M. Wheaton and S. Wong, "Quantitative Management of COTS-Based Systems Throughout the Program Life Cycle," Space 2003 (Long Beach, CA, Sep. 23–25, 2003), AIAA Paper 2003-6381.

J. M. Wicker, T-P. Yang, J. H. Ly, R. L. Wong, P. R. Dahl, and R. O. Rogers, "Low Cost Spacecraft Disturbance Rejection via Sensor Matching for Off-Gimbal Precision Pointing System," 2003 AIAA Guidance, Navigation, and Control Conference and Exhibit (Austin, TX, Aug. 11–14, 2003), AIAA Paper 2003-5827.

F. C. Wong and N. Y. Lao, "Economic Value of Remote Sensing Imagery for Agricultural Applications," IEEE Aerospace Conference, Vol. 8 (Mar. 8–15, 2003), pp. 8-3815–8-3829.

H. T. Yura and S. G. Hanson, "Comment: Absolute Measurement of Roughness and Lateral-Correlation Length of Random Surfaces by Use of the Simplified Model of Image-Speckle Contrast," Applied Optics, Vol. 42, No. 14, pp. 2521–2522 (May 10, 2003).

A. Zimmerman, "Self-Discharge Losses in Lithium-ion Cells," 1st International Energy Conversion Engineering Conference (Portsmouth, VA, Aug. 17–21, 2003), AIAA Paper 2003-5985.

Patents

W. F. Buell et al., "Method and System for Processing Laser Vibrometry Data Employing Bayesian Statistical Processing Techniques," U.S. Patent No. 6,672,167, Jan. 2003.

Developed as an alternative to FM-discriminator, spectrogram processing, and time-frequency techniques, a Bayesian statistical data-processing method improves the performance of laser vibrometry systems, which are used for noncontact measurement of an object's vibration. The method employs a statistical (Bayesian) signal-processing technique to process one or more mathematical models of an object's vibration along with laser vibrometry and other prior data for a system under observation. The method exhibits significantly improved performance in determining vibrational frequency, particularly when measurement time is limited to a few vibrational cycles. An iterative procedure then produces the full vibrational spectrum of the object under observation.

C. M. Heatwole, L. K. Herman, G. M. Manke, B. T. Hamada, "Fault Detection Pseudo Gyro," U.S. Patent No. 6,681,182, Jan. 2003.

Designed to improve the reliability and lifetime of flight systems, a software "pseudo gyro" can help detect failures in hardware gyros. The pseudo gyro operates as part of the attitude control and reference system. It provides accurate relative vehicular position and angular velocity by analyzing external torques and computing the momentum transfer between the satellite bus and its appendages. It can be used to monitor the performance of any number of hardware gyros, providing on-orbit checks of functionality and performance. It can identify gyros with anomalous performance and track long-term performance trends. It can identify anomalous performance in the hardware used to generate data for computation, such as stepper motors, encoders, angular-orientation sensors, tachometers, and reaction wheels. When used to supplement an attitude control system, the pseudo gyro enables higher reliability, longer service life, lower power consumption, and more accurate angular velocity rates within high-bandwidth operations

T. M. Nguyen, J. Yoh, C. C. Wang, D. M. Johnson, "High-Power Amplifier Predistorter System," U.S. Patent No. 6,680,648, Jan. 2003.

An adaptive system distorts an input signal before high-power amplification to compensate for undesired amplitude and phase distortion while reducing spectral regrowth. The predistortion ensures that the signal, when amplified, will maintain the same power spectrum after baseband filtering. Based on closed-loop feedback of the amplifier output, the system can change the amount of signal distortion and thus can linearize the output of a high-power amplifier having variable or unknown characteristics. The feedback is used to gauge the input and output signals in a complex form and at baseband. The adaptive predistortion processing algorithm can be implemented onboard a satellite.

G. E. Peterson, "Method and System for Controlling the Eccentricity of a Near-Circular Orbit," U.S. Patent No. 6,672,542, Jan. 2003.

This patent describes an efficient method for nudging a low Earth satellite into a "frozen" orbit—that is, an orbit that maintains the same perigee location in inertial space with nonvarying eccentricity. Frozen orbits facilitate satellite-to-satellite linkage, altimetry control, and collision avoidance. Changes in eccentricity are achieved through controlled burns at either the apogee or perigee of the orbit, depending upon the satellite's location. Burn targeting can be implemented, for example, via a controller that executes a stationkeeping algorithm that uses along-track burns to slowly change the eccentricity. These burns are conducted in concert with the normal along-track burns necessary to compensate for the effects of drag. Thus, the change in eccentricity is achieved without interfering with mission operations and without consuming additional fuel.

J. J. Poklemba, G. S. Mitchell, "Quadrature Vestigial Sideband Digital Communications Method," U.S. Patent No. 6,606,010, Aug. 2003.

A new communications technique known as quadrature vestigial sideband (QVSB) signaling makes more efficient use of bandwidth in transmitting digital data. When compared with conventional transmission formats, the QVSB technique can achieve twice the throughput capacity with relatively little degradation in the signal-to-noise ratio. This modulation scheme achieves its improved spectral occupancy by placing overlapping independent data streams on each of two quadrature carriers. This form of cross-coupled data signaling is akin to transmission with a controlled form of intersymbol interference. A quadrature-crosstalk, maximum-likelihood-sequence estimator implements a Viterbi decoding algorithm to unravel the intersymbol interference and provide estimated data sequence outputs with a low bit-error ratio. The receiver is a coherently aided demodulator structure, whose time- and phase-reference synchronization loops are aided by the data sequence output estimates.

E. Y. Robinson, "Spacecraft for Removal of Space Orbital Debris," U.S. Patent No. 6,655,637, Dec. 2003.

SA spacecraft equipped with a grabbing mechanism can capture a piece of orbiting debris and remove it from orbit. The grabber uses inflatable articulating fingers that extend in various directions. Motors control tension lines that extend through loops in the fingers, pulling and releasing them as required to bend and secure them around the target object. An inflatable sphere or other high-drag device is then deployed to increase drag on an object in low Earth orbit, thereby pulling it slowly down into the atmosphere where it will burn up. For objects in upper orbits, this inflatable sphere can serve as a solar wind collector to gradually push them into disposal orbits; onboard thrusters can also be used for orbit removal and transfer of the object to the super synch galactic necropolis. The debris-removal spacecraft includes conventional components such as ranging sensors, navigation processors, and propulsion systems. It can be used as a single autonomous unit or bundled with others to remove multiple objects from orbit. This deorbit technique offers a simple alternative for attaching propulsion and guidance systems to space debris.

J. S. Swenson and R. C. Cole, "Method of Forming Patterned Metalization on Patterned Semiconductor Wafers," U.S. Patent No. 6,677,227, Jan. 2003.

Using standard processes, this method creates metalized via connections between semiconductor microcircuits and microelectromechanical systems (MEMS). It offers a process bridge between substrates containing CMOS devices and overlying MEMS and chemical sensor layers using foundry-incompatible materials. The CMOS wafer can have large-diameter and small features typical of foundries, but a MEMS shop doing this metalization does not need commensurate lithography equipment. An example starts with a CMOS wafer, with vias newly etched through the last insulation layer. New photoresist is developed away at vias and where wires are desired. Gold is deposited, with good step coverage. A thick planarization layer is spun on and etched back until only dimples remain filled. Etching removes the gold, except under the remaining planarization at vias and wires. The planarization and photoresist are then stripped away.

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