An investigation of very small satellite miniaturisation techniques is presented, focusing on sub-kilogram technologies targeted at space sensor network applications. Distributed space mission concepts are emerging for scientific and remote sensing applications. This architecture will enable observation of real-time multi-point phenomena. Space economics and environmental concerns dictate a cost-effective mass-producible low-mass satellite for brief but essential missions in low Earth orbit....
Topics: DTIC Archive, Barnhart, David J, SURREY UNIV GUILDFORD (UNITED KINGDOM) SURREY SPACE CENTRE,...
Ferrnmagnetic materials are essential for data recording devices. For inductive or magnetoresistive (MR) sensors softmagnetic thin layer systems are used. Optimal performance of these layers requires homogeneous magnetic properties, especially a pronounced uniaxial magnetic anisotropy. Furthermore, microstructural imperfections and residual stresses influence the magnetic structure in the layer system. Barkhausen Noise Microscopy enables the characterization of such thin layers. By cycling the...
Topics: DTIC Archive, Hoffmann, Jochen, Meyendorf, Norbert, Altpeter, Iris, DAYTON UNIV OH CENTER FOR...
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May 22, 2012
05/12
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Minteer, Shelley D
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Includes bibliographical references and index
Topics: Cellular biology, Molecular biology, Pharmacology, Science/Mathematics, Laboratory Manuals,...
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Jun 18, 2010
06/10
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NON
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ELECTRICAL PROPERTIES OF HIGH RELIABILITY COMPUTER GRADE MINIATURE CAPACITORS
Topics: CAPACITORS, ELECTRICAL PROPERTIES, MINIATURE ELECTRONIC EQUIPMENT, MINIATURIZATION, RELIABILITY,...
The topics include: 1) Distributed Aerodynamic Sensing and Processing Toolbox; 2) Collaborative Supervised Learning for Sensor Networks; 3) Hazard Detection Software for Lunar Landing; 4) Onboard Nonlinear Engine Sensor and Component Fault Diagnosis and Isolation Scheme; 5) Network-Capable Application Process and Wireless Intelligent Sensors for ISHM; 6) Interface Supports Multiple Broadcast Transceivers for Flight Applications; 7) FPGA Sequencer for Radar Altimeter Applications; 8) Miniature...
Topics: NASA Technical Reports Server (NTRS), TECHNOLOGY UTILIZATION, NASA PROGRAMS, HUMAN FACTORS...
The Technological Research and Development Authority (TRDA) and NASA-KSC entered into a cooperative agreement in March of 1994 to achieve the utilization and commercialization of a technology development for benefiting both the Space Program and U.S. industry on a "dual-use basis". The technology involved in this transfer is a new, unique Universal Conditioning Amplifier (USCA) used in connection with various types of transducers. The project was initiated in partnership with I-Net...
Topics: NASA Technical Reports Server (NTRS), AMPLIFIER DESIGN, OPERATIONAL AMPLIFIERS, TRANSDUCERS, SIGNAL...
We have explored both monolithic and hybrid assembly techniques, with miniaturization the main goal in either case. The hybrid approach that we will describe makes use of a submount of laser manufacturing, but made from a material chosen for a specific thermal expansion coefficient, either high or low compared to Inp, to obtain either enhanced or reduced temperature tuning. To increase the effectiveness of the differential expansion, we also developed a strain magnifying structure based on a...
Topics: DTIC Archive, Coldren, L A, CALIFORNIA UNIV SANTA BARBARA DEPT OF ELECTRICAL AND COMPUTER...
If global force projection through rapid deployability is the Army Transformation vision, then Micro-electro Mechanical Systems (MEMS) are one of the key technological building blocks for the Objective Force. Size and weight are the fundamental characteristics that must be satisfied to create rapidly deploying forces. Versatility, transportability, and small sustainability footprints are the hallmarks of this next generation of platforms. Deployability is the key, deployability of the force,...
Topics: DTIC Archive, Bianco, Stephen G, ARMY WAR COLL CARLISLE BARRACKS PA, *MICROELECTRONICS, *ARMY,...
Topics covered include: Dual Cryogenic Capacitive Density Sensor; Hail Monitor Sensor; Miniature Six-Axis Load Sensor for Robotic Fingertip; Improved Blackbody Temperature Sensors for a Vacuum Furnace; Wrap-Around Out-the-Window Sensor Fusion System; Wide-Range Temperature Sensors with High-Level Pulse Train Output; Terminal Descent Sensor Simulation; A Robust Mechanical Sensing System for Unmanned Sea Surface Vehicles; Additive for Low-Temperature Operation of Li-(CF)n Cells; Li/CFx Cells...
Topics: NASA Technical Reports Server (NTRS), ANTENNA ARRAYS, BRIGHTNESS TEMPERATURE, CARBON NANOTUBES,...
The development of a digital autopilot for the XBQM-106 Mini-Remotely Piloted Vehicle(RPV) is described. The design is based on the RCA CDP-1802 microprocessor with ultra-low component cost as a primary goal. The digital autopilot is developed through the breadboard stage, and performance testing is accomplished via hybrid simulation. First, aircraft transfer functions are derived from aerodynamic wind tunnel data. Then a complete control analysis is made of the existing analog autopilot,...
Topics: DTIC Archive, Koger, Olin D, AIR FORCE INSTITUTE OF TECHNOLOGY WRIGHT-PATTERSON AFB OH SCHOOL OF...
The thermal conductivity and specific heat of NdP5O14 have been measured using a dynamic electrical heating technique. The values of the thermal conductivity tensor elements (in W/cm-K) are Lambda sub a = .021, Lambda sub b = .00966, and Lambda sub c = .014. The specific heat is 0.141 cal/g-K, in excellent agreement with the value of 0.139 cal/g-K that was measured by differential scanning calorimetry. We have calculated the time-dependent heating effects of typical flash-lamp-excited round and...
Topics: DTIC Archive, Chinn,Stephen R, MASSACHUSETTS INST OF TECH LEXINGTON LINCOLN LAB, *NEODYMIUM LASERS,...
EMG detection is critical in gait analysis. Localized EMG detection usually calls for invasive method using needle electrode. Body surface EMG provides global information about the muscle activity of a general area. This global information is not as useful compared with the localized EMG signal Concentric ring electrode with build-in amplifier provides superior localized EMG signal from body surface. A light weight (2 gm) miniature (15mm in diameter 3.5 mm in thickness) active concentric ring...
Topics: DTIC Archive, Lu, Chih-Cheng, NATIONAL HEALTH RESEARCH INST TAIPEI (TAIWAN) DIV OF MEDICAL...
This paper describes the development of a 6-degree of freedom (6-DOF), nonlinear, miniature rotary-wing unmanned aerial vehicle (RW UAV) simulation environment using MathWorks Simulink simulation software. In addition to the modeling process, this research also conducts flight-path controller design using Proportional Integral Derivative (PID) control. This model's development is motivated by the desire to enable a rapid prototyping platform for design and implementation of various flight...
Topics: DTIC Archive, NAVAL POSTGRADUATE SCHOOL MONTEREY CA, *MATHEMATICAL MODELS, *ROTARY WING AIRCRAFT,...
The miniaturized Moessbauer (MB) spectrometers MIMOS II [1] on board of the two Mars Exploration Rovers Spirit and Opportunity have obtained more than 600 spectra of more than 300 different rock and soil targets [2-7]. Both instruments have simultaneously collected 6.4 keV X-ray and 14.4 keV .-ray spectra in backscattering geometry [1]. With Spirit's MB spectrometer, 6.4 keV and 14.4 keV spectra have been obtained for all targets through sol 461. After this date, only 14.4 keV spectra were...
Topics: NASA Technical Reports Server (NTRS), MOSSBAUER EFFECT, X RAY SPECTRA, PENETRATION, SOILS, MARS...
Contaminating microorganisms pose a serious potential risk to the crew's well being and water system integrity aboard the International Space Station (ISS). We are developing a gene-based microbial monitor that functions by replicating specific segments of DNA as much as 10(exp 12) x. Thus a single molecule of DNA can be replicated to detectable levels, and the kinetics of that molecule's accumulation can be used to determine the original concentration of specific microorganisms in a sample....
Topics: NASA Technical Reports Server (NTRS), MICROORGANISMS, GENES, DEOXYRIBONUCLEIC ACID, SPACECRAFT...
The MURI research has been comprised of four interconnected Thrust Areas: Enzyme Engineering of Bio-electrocatalysts; Oxidation of Complex Biofuel; Electron Transfer Fundamentals; and Interface Architecture and Transport Phenomena in Bio-electrodes. The program established in summary that enzymatic biofuel cells present a viable candidate for ultimate miniaturization of power sources because it is a class of energy conversion devices that employ molecular electrocatalysts - enzymes and...
Topics: DTIC Archive, NEW MEXICO UNIV ALBUQUERQUE, *ELECTROCATALYSTS, *ENZYME CHEMISTRY, BIOELECTRICITY,...
The main goal of the work under this Grant was the clarification of the scaling properties of Hall thrusters, with a view to both, miniaturization, and expansion to high power. This goal was pursued through two complementary efforts, one addressing the scaling issues and technological problems associated with miniaturization of classically arranged Hall thrusters, and the other continuing the fundamental physical modeling work on Hall thrusters, which underlies all scaling work. In addition,...
Topics: DTIC Archive, Martinez-Sanchez, Manual, MASSACHUSETTS INST OF TECH CAMBRIDGE DEPT OF AERONAUTICS...
Oxygen sensors based on oxygen-conducting ceramics have the advantage of simplicity in construction and operation. However, currently available oxygen sensors of this kind require too high temperatures (above 600 0C) to operate. During Phase I, Nanomaterials Research Corporation (NRC) aimed to established the proof-of-concept for developing low-temperature, low power consuming, miniaturized oxygen sensors based on YSB materials. The objectives of the Phase I work included fabricating an oxygen...
Topics: DTIC Archive, Yadav, Tapesh, NANOMATERIALS RESEARCH CORP TUCSON AZ, *DETECTORS, *ELECTROCHEMISTRY,...
This document presents the results of a survey of the state-of-the- art as applied to cryocoolers to cool small superconducting devices. The survey included visits to over 100 facilities involved in the production or development of small cryocoolers in the United States, Japan, Europe. Specifications of commercially available cryocoolers having capacities of one of five watts in the 80 to 4 K range are presented. The survey was sponsored by the Office of Naval Research. Keywords include:...
Topics: DTIC Archive, Smith, Jr , J L, NAVAL RESEARCH LAB WASHINGTON DC, *COOLING AND VENTILATING...
The foregoing science discussions, the required measurements and the detailed implementation plans should provide ample evidence in support of the contention that geospace multiprobes are the next logical step forward in exploration of our environment. The advancement of technology in areas such as mechanical engineering, power systems, circuit miniaturization, high-capacity data storage, and innovative propulsion systems all allow the implementation of multiple satellite configurations within...
Topics: NASA Technical Reports Server (NTRS), DATA STORAGE, MINIATURIZATION, PLANETARY ENVIRONMENTS,...
Congress directed the Department of Defense (DoD), in section 2845 of the National Defense Authorization Act of 2010, to conduct a study to assess the feasibility of developing nuclear power plants on military installations. This study was conducted to meet this requirement. The study shows that small nuclear power plants can contribute to DoD missions by increasing energy assurance while reducing carbon emissions and reliance on fossil fuels for electricity; significant time and resources will...
Topics: DTIC Archive, CENTER FOR NAVAL ANALYSES ALEXANDRIA VA RESOURCE ANALYSIS DIV, *FEASIBILITY STUDIES,...
This paper details the flight configuration and pre-flight performance test results of the fifth generation cryogenic capillary pumped loop (CCPL-5). This device will fly on STS-95 in October 1998 as part of the CRYOTSU Flight Experiment. This flight represents the first in-space demonstration of a CCPL, a miniaturized two-phase fluid circulator for thermally linking cryogenic cooling sources to remote cryogenic components. CCPL-5 utilizes N2 as the working fluid and has a practical operating...
Topics: NASA Technical Reports Server (NTRS), PERFORMANCE TESTS, CRYOGENIC COOLING, SPACE TRANSPORTATION...
Inside diametar wafering equipment, blades and processes were used to develop methods to produce large areas of silicon sheet. Modifications to a 16 inch STC automated saw included: programmable feed system, crystal rotating system, and STC dynatrack blade monitoring and control system. By controlling the plating operation and by grinding of the cutting edge, 16 inch ID blades with a cutting edge thickness of .22 mm can be produced. Crystal rotation mechanism was used to slice 100 mm diameter...
Topics: NASA Technical Reports Server (NTRS), CUTTING, FORMING TECHNIQUES, INGOTS, SAWS, SILICON FILMS,...
In Phase 1 of the PINS program we were able to demonstrate a multimode operating Cr:LiCAF miniaturized laser generating up to 300 mW of output power. In addition we developed a filter that enables tuning over 0.9 nm and single-mode operation. Initial demonstrations with test devices showed single-mode operation up to 20mW of output power with linewidth on the order 5MHz. We are confident, that further development could bring the single mode output power beyond 150mW and the linewidth well below...
Topics: DTIC Archive, Kaertner, Franz X, MASSACHUSETTS INST OF TECH CAMBRIDGE DEPT OF ELECTRICAL...
Autonomous estimation of the altitude of an Unmanned Aerial Vehicle (UAV) is extremely important when dealing with flight maneuvers like landing, steady flight, etc. Vision based techniques for solving this problem have been underutilized. In this thesis, we propose a new algorithm to estimate the altitude of a UAV from top-down aerial images taken from a single on-board camera. We use a semi-supervised machine learning approach to solve the problem. The basic idea of our technique is to learn...
Topics: DTIC Archive, MINNESOTA UNIV DULUTH, *HELICOPTERS, *AERIAL PHOTOGRAPHY, OPTIMIZATION, THESES,...
Much of the hardware of high technology is characterized by miniaturization, extremely close tolerances and position control within fractions of a micron. Both national security and primacy in international economics are directly related to strength in the development of advanced precision systems and their production at low cost and high reliability. Comparing the status of precision engineering in the U.S. with that of Switzerland, Germany, and Japan, countries with enviable trade balances...
Topics: DTIC Archive, Modrey, J, PURDUE UNIV LAFAYETTE IN SCHOOL OF INDUSTRIAL ENGINEERING, *PRECISION,...
Detailed analysis and experimental data presented in this report show that longitudinal groove designs are crucial to increase the heat transport capacity of miniature heat pipes. The steady state mathematical models of a miniature axially grooved heat pipe with micro grooves are developed where the importance of the interfacial phenomena at the surfaces of the ultra thin is emphasized. The predicted capillary and boiling limitations as well as thermal resistance are compared to detailed...
Topics: DTIC Archive, Faghri, Amir, WRIGHT STATE UNIV DAYTON OH DEPT OF MECHANICAL AND MATERIALS...
Loop heat pipes (LHP) are efficient devices for heat transfer and use the basic principle of a closed evaporation-condensation cycle. The advantage of using a loop heat pipe over other conventional methods is that large quantities of heat can be transported through a small cross-sectional area over a considerable distance with no additional power input to the system. By using LHPs, it seems possible to meet the growing demand for high-power cooling devices. Although they are somewhat similar to...
Topics: NASA Technical Reports Server (NTRS), TEMPERATURE CONTROL, SPACECRAFT TEMPERATURE, HEAT PIPES,...
Miniature glow ignition internal combustion (IC) piston engines are an off-the-shelf technology that could dramatically increase the endurance of miniature electric power supplies and the range and endurance of small unmanned air vehicles provided their overall thermodynamic efficiencies can be increased to 15% or better. This thesis presents the first comprehensive analysis of small (500 g) piston engine performance. A unique dynamometer system is developed that is capable of making reliable...
Topics: DTIC Archive, MARYLAND UNIV COLLEGE PARK, *INTERNAL COMBUSTION ENGINES, *MINIATURIZATION, *PISTON...
A miniaturized solid-state optical spectrometer chip was designed with a linear gradient-gap Fresnel grating which was mounted perpendicularly to a sensor array surface and simulated for its performance and functionality. Unlike common spectrometers which are based on Fraunhoffer diffraction with a regular periodic line grating, the new linear gradient grating Fresnel spectrometer chip can be miniaturized to a much smaller form-factor into the Fresnel regime exceeding the limit of conventional...
Topics: NASA Technical Reports Server (NTRS), MINIATURIZATION, SIMULATION, SPECTROMETERS, FRESNEL...
The design of instrumentation for remote sensing presents special requirements in the areas of power consumption, long-term stability, and compactness. At the same time, the high sensitivity and resolution of the devices needs to be preserved. This paper will describe several instruments suitable for remote sensing developed under the sponsorship of the Defense Threat Reduction Agency (DTRA). The first is a system consisting of a mechanical cryocooler coupled with a high-purity germanium (HPGe)...
Topics: DTIC Archive, Berg, Lodewijk Van Den, CONSTELLATION TECHNOLOGY CORP LARGO FL, *RADIATION MONITORS,...
A survey of telemetry techniques for miniature and high-g applications is provided. The sum of many individual efforts is providing an expanding set of tools and techniques by which a new generation of flight tests is possible. Additionally, major thrusts have been made to substantially reduce the cost of key components and modules of the telemetry system. New capabilities in transmitters, power supplies, electronic packaging, and sensors are being developed.
Topics: DTIC Archive, D Amico, William P., Jr, ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD, *GUN LAUNCHED,...
Steady-state and frequency response calibration of a microfabricated heat-flux sensor have been completed. This sensor is batch fabricated using standard, micromachining techniques, allowing both miniaturization and the ability to create arrays of sensors and their corresponding interconnects. Both high-frequency and spatial response is desired, so the sensors are both thin and of small cross-sectional area. Thin-film, temperature-sensitive resistors are used as the active gauge elements. Two...
Topics: NASA Technical Reports Server (NTRS), TEMPERATURE MEASURING INSTRUMENTS, HEAT FLUX, SENSITIVITY,...
Research is being conducted at the LaRC to develop a telerobotic assembly system designed to construct large space truss structures. This research program was initiated within the past several years, and a ground-based test-bed was developed to evaluate and expand the state of the art. Test-bed operations currently use predetermined ('taught') points for truss structural assembly. Total dependence on the use of taught points for joint receptacle capture and strut installation is neither robust...
Topics: NASA Technical Reports Server (NTRS), AUTOMATIC CONTROL, COMPUTER VISION, IMAGE PROCESSING, LARGE...
The dissertation discusses a completely new concept for the realization of specific inductance construction forms, with which, in parallel construction, one might work on a multitude of coils integrated into processing usage. Firstly, the author sets out his principles for production and characterization; secondly, he describes the usage process in detail, so as to provide examples for his empirical research. The next and largest chapter focuses on the deformation of the microstructures,...
Topics: DTIC Archive, Wiest, Florian, UNIVERSITAET DER BUNDESWEHR MUENCHEN NEUBIBERG (GERMANY) FAKULTAET...
Design and Development of VHF Antennas for Space Borne Signal of Opportunity Receivers for Cubesat Platforms. Space borne microwave remote sensors at VHF/UHF frequencies are important instruments to observe reflective properties of land surfaces through thick and heavy forestation on a global scale. One of the most cost effective ways of measuring land reflectivity at VHF/UHF frequencies is to use signals transmitted by existing communication satellites (operating at VHF/UHF band) as a signal...
Topics: NASA Technical Reports Server (NTRS), VERY HIGH FREQUENCIES, ANTENNAS, SATELLITE-BORNE INSTRUMENTS,...
An ultraminiature light source using a double-spiral shaped tungsten filament includes end contact portions which are separated to allow for radial and length-wise unwinding of the spiral. The double-spiral filament is spaced relatively far apart at the end portions thereof so that contact between portions of the filament upon expansion is avoided. The light ource is made by fabricating a double-spiral ultraminiature tungsten filament from tungsten foil and housing the filament in a ceramic...
Topics: NASA Technical Reports Server (NTRS), BROADBAND, LIGHT SOURCES, MANUFACTURING, MINIATURIZATION,...
A miniature electrostatic ion thruster is proposed that, with one exception, would be based on the same principles as those of the device described in the previous article, "Miniature Bipolar Electrostatic Ion Thruster". The exceptional feature of this thruster would be that, in addition to using electric fields for linear acceleration of ions and electrons, it would use a magnetic field to rotationally accelerate slow electrons into the ion stream to neutralize the ions.
Topics: NASA Technical Reports Server (NTRS), ELECTROSTATICS, ION ENGINES, MINIATURIZATION, MAGNETS,...
The mission of the Micro-sized Microwave Atmospheric Satellite (MicroMAS) is to collect useful atmospheric images using a miniature passive microwave radiometer payload hosted on a low-cost CubeSat platform. In order to collect this data, the microwave radiometer payload must rotate to scan the ground-track perpendicular to the satellite's direction of travel. A custom motor assembly was developed to facilitate the rotation of the payload while allowing the spacecraft bus to remained fixed in...
Topics: NASA Technical Reports Server (NTRS), SATELLITES, MICROWAVE RADIOMETERS, MINIATURIZATION, PAYLOADS,...
Radially rotating miniature heat pipes for turbine blade cooling are studied by employing appropriate flow and heat transfer modeling as well as experimental tests. Extensive experimental tests on the heat pipes with different influential parameters are undertaken under a constructed high-speed rotating apparatus, and various effects of these parameters on the heat pipe performance are searched. Comprehensive analytical solutions for the heat pipe performance are also obtained, which are in...
Topics: DTIC Archive, Cao, Yiding, FLORIDA INTERNATIONAL UNIV MIAMI DEPT OF MECHANICAL ENGINEERING,...
A detailed description of the assembly procedure of the Floating Spacecraft Simulator (FSS) has been produced for the Naval Postgraduate Schools Spacecraft Robotics Laboratory. This procedure has been used to assemble an additional FSS, resulting in a total of three operational units. The second part of the research effort was devoted to the design of a miniaturized version of the FSS. Due to the finite size of the testbed, it was desirable to reduce the footprint of the FSS to increase the...
Topics: DTIC Archive, Park,Jonathan, NAVAL POSTGRADUATE SCHOOL MONTEREY CA MONTEREY United States,...
This symposium included the following topics: Properties of Piezolectric Resonator Materials; Filters; Measurements and Specifications; Theory and Design of Crystal Resonators; Miniature Resonators; Theory and Design of Crystal Resonators II; Surface Acoustic Wave Devices; Oscillators and Circuits; Atomic and Molecular Frequency Standards.
Topics: DTIC Archive, ARMY LAB COMMAND FORT MONMOUTH NJ ELECTRONICS TECHNOLOGY AND DEVICES LAB, *FREQUENCY...
A combined experimental and analytical investigation was conducted in order to identify and better understand the phenomena which govern the performance limitations and operating characteristics of micro heat pipes - heat pipes so small that the mean curvature of the vapor-liquid interface is comparable in magnitude to the reciprocal of the hydraulic radius of the flow channel. The analytical portion of the investigation began by developing a steady-state model in which the effects of the...
Topics: DTIC Archive, Peterson, G P, TEXAS A AND M UNIV COLLEGE STATION DEPT OF MECHANICAL ENGINEERING,...
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Production of high molecular weight polyisoprene latex is enhanced by administering to plants, particularly Guayule Plants, an amine containing at least one two-carbon chain substituent and preferably substituted trialkylamine of the general structure: ##STR1## where R.sub.4, R.sub.5 and R.sub.6 are alkyl, preferably ethyl and at least one of R.sub.4, R.sub.5 and R.sub.6 is preferably an electron withdrawing group substituted aryloxy or arylthio ethyl group.
Topics: MOSSBAUER EFFECT, TARGETS, X RAY SPECTRA, PENETRATION, SOILS, MARS SURFACE, MINERALOGY,...
SRI investigated ways to harvest otherwise wasted energy from walking. The recovered energy, potentially on the order of 1-2 W per boot, can be used by a soldier to supplement battery power, as an emergency backup source of power, for specialized on-board boot functions such as inertia navigation, and, in the future, to enhance walking and other mobility performance. The approach used by SRI was electroactive polymers (EAP's), rubbery materials that generate electrical power when stretched and...
Topics: DTIC Archive, Pelrine, Ronald E, SRI INTERNATIONAL MENLO PARK CA, *POLYMERS, *GENERATORS, *BOOTS,...
One of the most crucial requirements of modern space missions is the miniaturization of spacecraft and satellites. The miniaturization is tightly connected with new space technologies promoted by the Air Force, DARPA, and NASA, such as spacecraft formation flying, that implies two or more spacecraft that operate synchronously in a controlled spatial configuration. This, in turn, necessitates the development of new propulsion systems able to deliver precise impulse bits while meeting strict...
Topics: DTIC Archive, Ahmed, Zeeshan, CALIFORNIA UNIV LOS ANGELES, *ATTITUDE CONTROL SYSTEMS, *NUMERICAL...
A system of miniature radio interferometer terminals was proposed for the measurement of vector baselines with uncertainties ranging from the millimeter to the centimeter level for baseline lengths ranging, respectively, from a few to a few hundred kilometers. Each terminal would have no moving parts, could be packaged in a volume of less than 0.1 cu m, and would operate unattended. These units would receive radio signals from low-power (10 w) transmitters on earth-orbiting satellites. The...
Topics: NASA Technical Reports Server (NTRS), INTERFEROMETERS, MINIATURIZATION, GEODESY, RADIO SIGNALS,...
Discussed here are the writing of a data acquisition code and the installation and testing of new pressure and temperature instrumentation to be used in the testing and evaluation of miniature heat flux sensors. A brief summary of the problem which led to the need for these tests is presented as well as a proposed data acquisition program and the results of investigations of two measurement systems, the Omega OM-900 temperature sensing system and the Scani-Valve Hyscan pressure measurement...
Topics: NASA Technical Reports Server (NTRS), AERODYNAMICS, DATA ACQUISITION, HEAT FLUX, HEAT TRANSFER,...
Solder joints provide both electrical and mechanical interconnections between a silicon chip and the packaging substrate in an electronic application. The thermomechanical cycling in the solder causes numerous reliability challenges, mostly because of the mismatch of the coefficient of thermal expansion between the silicon chip and the substrate. The actual transition to lead-free solders and the trend towards hotter-running, miniaturized and higher current density chips aggravate this...
Topics: DTIC Archive, Reuse, Rolando, NAVAL POSTGRADUATE SCHOOL MONTEREY CA DEPT OF MECHANICAL AND...
Satellites of the 'micro' class and smaller require scalable propulsion systems that minimize mass, volume and power. With a substantial reduction in ionizer size, ion thrusters may fulfill all of these requirements. This work explores field ionization with nanotube arrays for a highly-scalable ionizer. Fabrication and testing of carbon nanotube pillar array (CPA) ionizers is undertaken at the Nanotechnology Center, NASA Ames Research Center. The devices are built using conventional...
Topics: DTIC Archive, NAVAL POSTGRADUATE SCHOOL MONTEREY CA, *CARBON NANOTUBES, *IONIZATION, LOW PRESSURE,...
