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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 433 records · Page 24
All sourcesNASA NTRSDOE OSTI
NASA NTRS2011

Cable Tester Box

Cables are very important electrical devices that carry power and signals across multiple instruments. Any fault in a cable can easily result in a catastrophic outcome. Therefore, verifying that all cables are built to spec is a very important part of Electrical Integration Procedures. Currently, there are two methods used in lab for verifying cable connectivity. (1) Using a Break-Out Box and an ohmmeter this method is time-consuming but effective for custom cables and (2) Commercial Automated Cable Tester Boxes this method is fast, but to test custom cables often requires pre-programmed configuration files, and cables used on spacecraft are often uniquely designed for specific purposes. The idea is to develop a semi-automatic continuity tester that reduces human effort in cable testing, speeds up the electrical integration process, and ensures system safety. The JPL-Cable Tester Box is developed to check every single possible electrical connection in a cable in parallel. This system indicates connectivity through LED (light emitting diode) circuits. Users can choose to test any pin/shell (test node) with a single push of a button, and any other nodes that are shorted to the test node, even if they are in the same connector, will light up with the test node. The JPL-Cable Tester Boxes offers the following advantages: 1. Easy to use: The architecture is simple enough that it only takes 5 minutes for anyone to learn how operate the Cable Tester Box. No pre-programming and calibration are required, since this box only checks continuity. 2. Fast: The cable tester box checks all the possible electrical connections in parallel at a push of a button. If a cable normally takes half an hour to test, using the Cable Tester Box will improve the speed to as little as 60 seconds to complete. 3. Versatile: Multiple cable tester boxes can be used together. As long as all the boxes share the same electrical potential, any number of connectors can be tested together.

Lee, Jason H.↗
DOE OSTI2022

Atomic-Scale Modulation of Synthetic Magnetic Order in Oxide Superlattices

We report atomic-scale precision control of magnetic interactions facilitates a synthetic spin order useful for spintronics, including advanced memory and quantum logic devices. Conventional modulation of synthetic spin order has been limited to metallic heterostructures that exploit Ruderman–Kittel–Kasuya–Yosida interaction through a nonmagnetic metallic spacer; however, they face issues arising from Joule heating and/or electric breakdown. The practical realization and observation of a synthetic spin order across a nonmagnetic insulating spacer will lead to the development of spin-related devices with a completely different concept. Herein, the atomic-scale modulation of the synthetic spiral spin order in oxide superlattices composed of ferromagnetic metal and nonmagnetic insulator layers is reported. The atomically controlled superlattice exhibits an oscillatory magnetic behavior, representing the existence of a spiral spin structure. Depth-sensitive polarized neutron reflectometry evidences modulated spiral spin structures as a function of the nonmagnetic insulator layer thickness. Atomic-scale customization of the spin state can move the field one step further to actual spintronic applications.

74 ATOMIC AND MOLECULAR PHYSICS↗
NASA NTRS2002

Phase-Shifting Liquid Crystal Interferometers for Microgravity Fluid Physics

The initial focus of this project was to eliminate both of these problems in the Liquid Crystal Point-Diffraction Interferometer (LCPDI). Progress toward that goal will be described, along with the demonstration of a phase shifting Liquid Crystal Shearing Interferometer (LCSI) that was developed as part of this work. The latest LCPDI, other than a lens to focus the light from a test section onto a diffracting microsphere within the interferometer and a collimated laser for illumination, the pink region contained within the glass plates on the rod-mounted platform is the complete interferometer. The total width is approximately 1.5 inches with 0.25 inches on each side for bonding the electrical leads. It is 1 inch high and there are only four diffracting microspheres within the interferometer. As a result, it is very easy to align, achieving the first goal. The liquid crystal electro-optical response time is a function of layer thickness, with thinner devices switching faster due to a reduction in long-range viscoelastic forces between the LC molecules. The LCPDI has a liquid crystal layer thickness of 10 microns, which is controlled by plastic or glass microspheres embedded in epoxy 'pads' at the corners of the device. The diffracting spheres are composed of polystyrene/divinyl benzene polymer with an initial diameter of 15 microns. The spheres deform slightly when the interferometer is assembled to conform to the spacing produced by the microsphere-filled epoxy spacer pads. While the speed of this interferometer has not yet been tested, previous LCPDIs fabricated at the Laboratory for Laser Energetics switched at a rate of approximately 3.3 Hz, a factor of 10 slower than desired. We anticipate better performance when the speed of these interferometers is tested since they are approximately three times thinner. Phase shifting in these devices is a function of the AC voltage level applied to the liquid crystal. As the voltage increases, the dye in the liquid crystal tends to become more transparent, thus introducing a rather large amount of error into the phase-shifting measurement. While that error can be greatly reduced by normalization, we prefer eliminating the source of the error. To that end, we have pursued development of a 'blend' of custom dyes that will not exhibit these properties. That goal has not yet been fully achieved. Guardalben, et al, presented a similar set of interferograms in a paper partially funded by this grant. Shearing interferometers are a second class of common path interferometers. Typically they consist of a thick glass plate optimized for equal reflection from the front and back surface. While not part of the original thrust of the project, through the course of laboratory work, we demonstrated a prototype of a shearing interferometer capable of phase shifting using a commercial liquid crystal retardation plate. A schematic of this liquid crystal shearing interferometer (LCSI) and a sample set of interferograms are in the reference. This work was also supported by the U.S. Department of Energy Office of Inertial Confinement Fusion under Cooperative Agreement No. DE-FC03-92SF19460, the University of Rochester, and the New York State Energy Research and Development Authority. The support of DOE does not constitute an endorsement by DOE of the views expressed in this article. Additional information is included in the original extended abstract.

Griffin, DeVon W.↗
NASA NTRS2012

Thermodynamic Vent System for an On-Orbit Cryogenic Reaction Control Engine

A report discusses a cryogenic reaction control system (RCS) that integrates a Joule-Thompson (JT) device (expansion valve) and thermodynamic vent system (TVS) with a cryogenic distribution system to allow fine control of the propellant quality (subcooled liquid) during operation of the device. It enables zero-venting when coupled with an RCS engine. The proper attachment locations and sizing of the orifice are required with the propellant distribution line to facilitate line conditioning. During operations, system instrumentation was strategically installed along the distribution/TVS line assembly, and temperature control bands were identified. A sub-scale run tank, full-scale distribution line, open-loop TVS, and a combination of procured and custom-fabricated cryogenic components were used in the cryogenic RCS build-up. Simulated on-orbit activation and thruster firing profiles were performed to quantify system heat gain and evaluate the TVS s capability to maintain the required propellant conditions at the inlet to the engine valves. Test data determined that a small control valve, such as a piezoelectric, is optimal to provide continuously the required thermal control. The data obtained from testing has also assisted with the development of fluid and thermal models of an RCS to refine integrated cryogenic propulsion system designs. This system allows a liquid oxygenbased main propulsion and reaction control system for a spacecraft, which improves performance, safety, and cost over conventional hypergolic systems due to higher performance, use of nontoxic propellants, potential for integration with life support and power subsystems, and compatibility with in-situ produced propellants.

Hurlbert, Eric A.↗
NASA NTRS2015

Low Earth Orbit Environmental Durability of Recently Developed Thermal Control Coatings

The Materials International Space Station Experiment provided a means to expose materials and devices to the low Earth orbit environment on the exterior of the International Space Station. By returning the specimens to Earth after flight, the specimens could be evaluated by comparison with pre-flight measurements. One area of continuing interest is thermal control paints and coatings that are applied to exterior surfaces of spacecraft. Though traditional radiator coatings have been available for decades, recent work has focused on new coatings that offer custom deposition or custom optical properties. The custom deposition of interest is plasma spraying and one type of coating recently developed as part of a Small Business Innovative Research effort was designed to be plasma sprayed onto radiator surfaces. The custom optical properties of interest are opposite to those of a typical radiator coating, having a combination of high solar absorptance and low infrared emittance for solar absorber applications, and achieved in practice via a cermet coating. Selected specimens of the plasma sprayed coatings and the solar absorber coating were flown on Materials International Space Station Experiment 7, and were recently returned to Earth for post-flight analyses. For the plasma sprayed coatings in the ram direction, one specimen increased in solar absorptance and one specimen decreased in solar absorptance, while the plasma sprayed coatings in the wake direction changed very little in solar absorptance. For the cermet coating deployed in both the ram and wake directions, the solar absorptance increased. Interestingly, all coatings showed little change in infrared emittance.

Optical Properties↗
NASA NTRS2020

An Embedded Planar-Foil Capacitor Material, FPGA Based Interposer, Aimed at Improving System Performance and Reduced Board Size for Space Based Electronics

This paper presents our work to date in developing, and testing an embedded planar-foil capacitor based interposer intended to be integrated together with high-density components such as Field Programmable Gate Arrays (FPGAs), and Application Specific Integrated Circuit (ASIC) applications. FPGA devices typically have a large number of I/O and power pins. The high speed enabled by these devices requires a large number of discrete bypass capacitors as close as possible to the power pins. These capacitors take up a considerable amount of the board area on the application circuit board. Our interposer replaces these components freeing up space of traditional bypass capacitors for other circuitry. Our Interposer focuses on the needs of Micro Semi’s RTG4 FPGA. We developed the interposer using COTS embedded foil capacitors. The Interposer is customized to the capacitance requirements for each of the FPGA banks. We evaluated three foil manufactures Oak Mitsui, 3M and TDK. The three different designs were evaluated, but we will focus on the Oak-Mitsui based Interposer that we constructed and tested. Through simulations, we validate the horizontal and vertical interconnect inductances, that FPGA decoupling requirements are met. The use of the interposer results in an overall reduction in our Printed Wiring Board (PWB) area.

Hunter, Don J↗
DOE OSTI2026

A microfluidic spore chamber for long-term imaging of single-spore hyphal development.

Understanding the life cycle of fungal spores is essential for elucidating their roles in pathogenesis, dispersal, and survival. However, studying spore development under controlled, spatially defined conditions remains challenging. Here, we present the Spore Chamber, a custom-built microfluidic platform engineered for parallel trapping and long-term imaging of individual spores under defined media conditions, enabling real-time visualization of hyphal development. Using Aspergillus fumigatus as a model organism, we demonstrate that sparse trapping of individual spores within size-matched trap geometries enables long-term time-lapse imaging of key developmental stages, including germination, polarized hyphal elongation, branching, and conidiophore formation. To assess the device's capacity to resolve morphogenetic responses to exogenous signals, we introduced lipochitooligosaccharides (LCOs) and short-chain chitooligosaccharides (COs). Rhizobium-derived, non-sulfated LCO (nsLCO) mixtures induced enhanced secondary branching (hyperbranching), a response not previously reported in A. fumigatus under these signal conditions, to our knowledge, whereas sulfated LCOs and CO4 did not significantly alter branching patterns. In addition, long-term confinement and imaging revealed rare developmental morphologies previously described primarily in mutant strains, including split conidiophore formation, elongated phialides, and stress-associated phenomena such as microcyclic conidiation, and chlamydospore development. Together, these results establish the Spore Chamber as a targeted microfluidic platform for single-spore phenotyping and long-term developmental analysis, with applications in fungal biology, chemical signaling studies, and host–microbe interaction research.

Antifungal screening↗
DOE OSTI2025

Dataset for "A Microfluidic Spore Chamber for Long-Term Imaging of Single-Spore Hyphal Development"

Understanding the life cycle of fungal spores is essential for elucidating their roles in pathogenesis, dispersal, and survival. However, studying spore development under controlled, spatially defined conditions remains challenging. Here, we present the Spore Chamber, a custom-built microfluidic platform engineered for parallel trapping and long-term imaging of individual spores under defined media conditions, enabling real-time visualization of hyphal development. Using Aspergillus fumigatus as a model organism, we demonstrate that sparse trapping of individual spores within size-matched trap geometries enables long-term time-lapse imaging of key developmental stages, including germination, polarized hyphal elongation, branching, and conidiophore formation. To assess the device’s capacity to resolve morphogenetic responses to exogenous signals, we introduced lipochitooligosaccharides (LCOs) and short-chain chitooligosaccharides (COs). Rhizobium-derived, non-sulfated LCO (nsLCO) mixtures induced enhanced secondary branching (hyperbranching), a response not previously reported in A. fumigatus under these signal conditions, to our knowledge, whereas sulfated LCOs and CO4 did not significantly alter branching patterns. In addition, long-term confinement and imaging revealed rare developmental morphologies previously described primarily in mutant strains, including split conidiophore formation, elongated phialides, microcyclic conidiation, and chlamydospore development. Together, these results establish the Spore Chamber as a targeted microfluidic platform for single-spore phenotyping and long-term developmental analysis, with applications in fungal biology, chemical signaling studies, and host–microbe interaction research. Videos of the observed phenomena are included in this data set.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2023

Synthetic Metal Atomic Layer Deposition Tool (Final Report)

As part of the Cyclotron Road program, Laminera Inc. worked towards development of atomic layer deposition process customizations and tool modifications to produce synthetic metal films at commercial scale and improve the film quality. Today's state-of-the-art in atomic layer deposited synthetic metal technology is only possible at a research-scale because current tools have practical limitations for scaling industrially and generating high conductivity films. Ultrathin, conformal synthetic metal films have many possible applications such as high surface area nanoporous electrodes for supercapacitors and water desalination devices; protective electrode coatings for electrochemical devices; seed layers for semiconductor device fabrication; or metallic component stabilizing coatings that enable enhanced storage density in next generation hard disk drives. The best synthetic metal conductive and plasmonic properties have been demonstrated using sputtering, which relies on high temperature sputtering with substrate dependent and directional growth limiting usage. This work explored refining process and tool modifications to create ultrathin, conformal, synthetic metal films that can be deposited with high quality over complex three-dimensional surfaces.

36 MATERIALS SCIENCE↗
DOE OSTI2023

A Smart Silicon Carbide Power Module With Pulse Width Modulation Over Wi-Fi and Wireless Power Transfer-Enabled Gate Driver, Featuring Onboard State of Health Estimator and High-Voltage Scaling Capabilities: Preprint

A wide range of utility applications require controllable switches with features such as high-voltage (HV) blocking and high-current carrying capacity especially at high pulse width modulation (PWM) frequency. Low and medium voltage utility applications such as motor drives and flexible AC transmission systems (FACTS) as well as solid state transformers (SST) could also benefit from a low-cost HV switching module. Wide band gap (WBG) semiconductors such as SiC and GaN MOSFETs are considered to be the present and next generation device choices, although they have their own limitations. For relatively HV applications with demanding thermal management, SiC is still the only choice, and GaN dominates the low voltage regime. This manuscript proposes a new half bridge power MOSFET module that is suitable for conventional H-bridge of multilevel configurations used in HV applications. Constructed from bare SiC dies, this half bridge module takes advantage of (1) optimized MOSFET placement inside the module, (2) customized heat exchanger, manifold and cooling, (3) integrated gate driver module with PWM over wi-fi to eliminate the need for low voltage signals, (4) wireless power transfer (WPT) enabled gate driver and other ancillary circuits, (5) and the option to incorporate an onboard state of health (SOH) estimator module onboard. The entire architecture has been designed and built at National Renewable Energy Laboratory (NREL), Golden, CO.

baseplate design↗
NASA NTRS2005

Reconfigurable Processing Module

To accommodate a wide spectrum of applications and technologies, NASA s Exploration System's Missions Directorate has called for reconfigurable and modular technologies to support future missions to the moon and Mars. In response, Langley Research Center is leading a program entitled Reconfigurable Scaleable Computing (RSC) that is centered on the development of FPGA-based computing resources in a stackable form factor. This paper details the architecture and implementation of the Reconfigurable Processing Module (RPM), which is the key element of the RSC system. The RPM is an FPGA-based, space-qualified printed circuit assembly leveraging terrestrial/commercial design standards into the space applications domain. The form factor is similar to, and backwards compatible with, the PCI-104 standard utilizing only the PCI interface. The size is expanded to accommodate the required functionality while still better than 30% smaller than a 3U CompactPCI(TradeMark)card and without the overhead of the backplane. The architecture is built around two FPGA devices, one hosting PCI and memory interfaces, and another hosting mission application resources; both of which are connected with a high-speed data bus. The PCI interface FPGA provides access via the PCI bus to onboard SDRAM, flash PROM, and the application resources; both configuration management as well as runtime interaction. The reconfigurable FPGA, referred to as the Application FPGA - or simply "the application" - is a radiation-tolerant Xilinx Virtex-4 FX60 hosting custom application specific logic or soft microprocessor IP. The RPM implements various SEE mitigation techniques including TMR, EDAC, and configuration scrubbing of the reconfigurable FPGA. Prototype hardware and formal modeling techniques are used to explore the performability trade space. These models provide a novel way to calculate quality-of-service performance measures while simultaneously considering fault-related behavior due to SEE soft errors.

Somervill, Kevin↗
DOE OSTI2026

Simulation-Based Validation of An Open-Source, Scalable Framework for Building Energy Management in Small and Medium-Sized Commercial Buildings

Abstract: Small and medium-sized commercial buildings (SMCBs) represent 94% of U.S. commercial buildings but encounter substantial obstacles in adopting Building Energy Management (BEM) systems. Current approaches exhibit fundamental limitations: vendor-specific API platforms restrict interoperability through proprietary ecosystems; commercial automation software demands extensive technical expertise and licensing costs; open-source IoT solutions lack native support for building automation protocols and semantic models. This paper introduces a configuration-driven web interface framework addressing the gap between smart device advancements and accessible BEM software infrastructure for SMCBs. The framework leverages VOLTTRON middleware integrated with an automated converter that processes unified YAML configurations into heterogeneous system files, reducing required configuration artifacts from six separate files to a single unified specification. The system architecture enables vendor-agnostic operation through BACnet and Modbus protocols while supporting semantic building model integration via automated Brick Schema parsing. Configuration-driven interfaces automatically adapt to diverse HVAC types without custom development. Simulation-based validation using BOPTEST demonstrates automatic interface generation between fan coil and hydronic systems, with the automated converter successfully generating all platform-specific outputs from the single YAML input. The result demonstrates the framework's capability to streamline BEM system deployment through reduced configuration complexity. This work bridges simulation capabilities with operational deployment, demonstrating how virtual testbeds validate generalizable software frameworks for real-world building automation.

Chung, Jihoon [ORNL] (ORCID:0000000184880815)↗
DOE OSTI2024

New systems in MOOSE

The Multiphysics Object-Oriented Simulation Environment (MOOSE) serves as a common library of classes between applications developed for advanced reactor analysis, fusion device engineering, spent fuel cask analysis, geochemistry studies, among other fields. These applications drive the development of the framework to meet their needs. Systems in MOOSE group capabilities that share a common purpose and generally common code. They can be leveraged by all downstream applications, providing extensive code re-use and shared maintenance. They facilitate the discovery by new users of the classes meeting at least partially their needs, and offer the same opportunities for customization as other systems. The addition of a new system to MOOSE opens new ways of solving or discretizing nonlinear problems, of performing distributed postprocessing, and a plethora of other needs. While new systems can be introduced in downstream applications rather than at the framework level, the framework team monitors common needs across the community and often triggers their addition. Documentation, training material, development needs can be centralized, limiting duplicated work across the community. The last three years have seen a large expansion in the capabilities of MOOSE. The supporting role of the framework in the Nuclear Energy Advanced Modeling and Simulation (NEAMS) program has created numerous feature requests to support neutronics, thermal hydraulics, computational fluid dynamics and thermo-mechanics simulations in the Griffin, SAM, Pronghorn and Bison applications respectively. Similarly, laboratory-directed research and development (LDRD) projects in additive manufacturing, high-Reynolds flow simulations, structure optimization also necessitate an expansion of the framework capabilities. This summary reports on the new systems created in MOOSE, their design, their capabilities and some of the relevant interfaces.

22 - GENERAL STUDIES OF NUCLEAR REACTORS↗
DOE OSTI2023

Development of polarization-sensitive optical coherence tomography imaging platform and metrics to quantify electrostimulation-induced peripheral nerve injury in vivo in a small animal model

Neuromodulation devices are rapidly evolving for the treatment of neurological diseases and conditions. Injury from implantation or long-term use without obvious functional losses is often only detectable through terminal histology. New technologies are needed that assess the peripheral nervous system (PNS) under normal and diseased or injured conditions. We aim to demonstrate an imaging and stimulation platform that can elucidate the biological mechanisms and impacts of neurostimulation in the PNS and apply it to the sciatic nerve to extract imaging metrics indicating electrical overstimulation. A sciatic nerve injury model in a 15-rat cohort was observed using a newly developed imaging and stimulation platform that can detect electrical overstimulation effects with polarization-sensitive optical coherence tomography. The sciatic nerve was electrically stimulated using a custom-developed nerve holder with embedded electrodes for 1 h, followed by a 1-h recovery period, delivered at above-threshold Shannon model k-values in experimental groups: sham control (SC, n = 5, 0.0 mA / 0 Hz), stimulation level 1 (SL1, n = 5, 3.4 mA / 50 Hz, and k = 2.57), and stimulation level 2 (SL2, n = 5, 6.8 mA / 100 Hz, and k = 3.17). The stimulation and imaging system successfully captured study data across the cohort. When compared to a SC after a 1-week recovery, the fascicle closest to the stimulation lead showed an average change of +4 % / – 309 % (SL1/SL2) in phase retardation and –79 % / – 148 % in optical attenuation relative to SC. Analysis of immunohistochemistry (IHC) shows a +1 % / – 36 % difference in myelin pixel counts and –13 % / + 29 % difference in axon pixel counts, and an overall increase in cell nuclei pixel count of +20 % / + 35 % . These metrics were consistent with IHC and hematoxylin/eosin tissue section analysis. The poststimulation changes observed in our study are manifestations of nerve injury and repair, specifically degeneration and angiogenesis. Optical imaging metrics quantify these processes and may help evaluate the safety and efficacy of neuromodulation devices.

60 APPLIED LIFE SCIENCES↗
NASA NTRS1995

The scheme machine: A case study in progress in design derivation at system levels

The Scheme Machine is one of several design projects of the Digital Design Derivation group at Indiana University. It differs from the other projects in its focus on issues of system design and its connection to surrounding research in programming language semantics, compiler construction, and programming methodology underway at Indiana and elsewhere. The genesis of the project dates to the early 1980's, when digital design derivation research branched from the surrounding research effort in programming languages. Both branches have continued to develop in parallel, with this particular project serving as a bridge. However, by 1990 there remained little real interaction between the branches and recently we have undertaken to reintegrate them. On the software side, researchers have refined a mathematically rigorous (but not mechanized) treatment starting with the fully abstract semantic definition of Scheme and resulting in an efficient implementation consisting of a compiler and virtual machine model, the latter typically realized with a general purpose microprocessor. The derivation includes a number of sophisticated factorizations and representations and is also deep example of the underlying engineering methodology. The hardware research has created a mechanized algebra supporting the tedious and massive transformations often seen at lower levels of design. This work has progressed to the point that large scale devices, such as processors, can be derived from first-order finite state machine specifications. This is roughly where the language oriented research stops; thus, together, the two efforts establish a thread from the highest levels of abstract specification to detailed digital implementation. The Scheme Machine project challenges hardware derivation research in several ways, although the individual components of the system are of a similar scale to those we have worked with before. The machine has a custom dual-ported memory to support garbage collection. It consists of four tightly coupled processes--processor, collector, allocator, memory--with a very non-trivial synchronization relationship. Finally, there are deep issues of representation for the run-time objects of a symbolic processing language. The research centers on verification through integrated formal reasoning systems, but is also involved with modeling and prototyping environments. Since the derivation algebra is basd on an executable modeling language, there is opportunity to incorporate design animation in the design process. We are looking for ways to move smoothly and incrementally from executable specifications into hardware realization. For example, we can run the garbage collector specification, a Scheme program, directly against the physical memory prototype, and similarly, the instruction processor model against the heap implementation.

Johnson, Steven D.↗
NASA NTRS1983

30/20 GHz spacecraft GaAs FET solid state transmitter for trunking and customer-premise-service application

Sixteen 30 dB 0.5 W amplifier modules were combined to satisfy the requirement for a graceful degradation. If one module fails, the output power drops by only 0.43 dB. Also, by incorporating all the gain stages within the combiner the overall combining efficiency is maximized. A 16 way waveguide divider combiner was developed to minimize the insertion loss associated with such a large corporate feed structure. Tests showed that the 16 way insertion loss was less than 0.5 dB. To minimize loss, a direct transition from waveguide to microstrip, using a finline on duroid substrate, was developed. The FETs fabricated on MBE grown material, demonstrated superior performances. For example, a 600 micrometer device was capable of 320 mW output power with 5 dB gain and 26.6% efficiency at 21 GHz. The 16 module amplifier gave 8.95 W saturated output power with 30 dB gain. The overall efficiency was 9%. The 3 dB bandwidth was 2.5 GHz. At 17.7 GHz the amplifier had 5 W output power and at 20.2 GHz it still had 4.4 W.

Saunier, P.↗
NASA NTRS2003

Going Places No Infrared Temperature Devices Have Gone Before

Exergen's IRt/c is a self-powered sensor that matches a thermocouple within specified temperature ranges and provides a predictable and repeatable signal outside of this specified range. Possessing an extremely fast time constant, the infrared technology allows users to measure product temperature without touching the product. The IRt/c uses a device called a thermopile to measure temperature and generate current. Traditionally, these devices are not available in a size that would be compatible with the Exergen IRt/c, based on NASA s quarterinch specifications. After going through five circuit designs to find a thermopile that would suit the IRt/c design and match the signal needed for output, Exergen maintains that it developed a model that totaled just 20 percent of the volume of the previous smallest detector in the world. Following completion of the project with Glenn, Exergen continued development of the IRt/c for other customers, spinning off a new product line called the micro IRt/c. This latest development has broadened applications for industries that previously could not use infrared thermometers due to size constraints. The first commercial use of the micro IRt/c involved an original equipment manufacturer that makes laminating machinery consisting of heated rollers in very tight spots. Accurate temperature measurement for this application requires close proximity to the heated rollers. With the micro IRt/c s 50-millisecond time constant, the manufacturer is able to gain closer access to the intended temperature targets for exact readings, thereby increasing productivity and staying ahead of competition.In a separate application, the infrared temperature sensor is being utilized for avalanche warnings in Switzerland. The IRt/c is mounted about 5 meters above the ground to measure the snow cover throughout the mountainous regions of the country.

Source record↗
NASA NTRS2000

NASA's Design and Development of a Field Goniometer Instrument Using Solid Works

With NASA suffering severe funding cutbacks, engineers at NASA are required to produce state-of-the-art hardware with limited personnel and financial resources. In light of these constraints, the new NASA mandate is to build better, faster and cheaper. In April of 1998, Stennis Space Center's Commercial Remote Sensing Program contracted to the Systems Engineering Division at NASA Ames Research Center to develop a device known as a Field Goniometer. A Field Goniometer is a device that measures bi-directional reflectance of a target, such as vegetation, relative to the sun and an imaging system in an aircraft or spacecraft. The device is able to provide a spectral fingerprint of the surface it is measuring in wavelengths from 350nm-2500nm using a hyperspectral imager. To accomplish this project, several obstacles had to be overcome. First, the design had to be completed in less than four months. Second, due to the complexity of the design, the use of solid modeling was highly desirable but most of the group's solid modelers were assigned to other jobs. Third, the amount of funding available from the customer was one half to one third the funding typically expended for a job of this nature. Our choices for this project were to design with standard 2-D CAD systems currently used in-house or train additional engineers on our existing solids package or purchase a new solid model package. The use of a 2D CAD system was very undesirable due to the complexity of the design. Using our existing solids modeler would have required a learning curve for our engineers that would be incompatible with our schedule. Prior to this project, a member of our design group researched the solid modeling industry and decided to purchase SolidWorks. After examining the product for ease of use, modeling capability, training time required and cost, we decided our highest probability of success would be to design with Solidworks. During the design phase, our fabrication group was able to provide input at the very early stages, which added significant benefit to the final product. Fabrication cost and schedule savings have been realized by having complex part geometries translated directly from the SolidWorks design models to Surfcam and other computer-aided manufacturing (CAM) software. This direct model translation capability optimized the fabrication processes. The end result was that we were able to successfully complete the project on time and on budget. Other advantages of using SolidWorks, as cited by the design team, include a rapid negotiation of the initial learning curve, the ability to develop solid model hardware prototypes (used to communicate the design intent to both the customer and the fabricator), and the ability to work as a team collaborating on a large, complex model. These types of tools and efforts represent our response to NASA's challenge to produce higher quality products within shorter design and fabrication times.

Turner, Mark↗