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At least 145 records · Page 8

Method and apparatus for an insulating glazing unit and compliant seal for an insulating glazing unit

A vacuum insulating glazing unit (VIGU) comprises two or more glass lites (panes) spaced apart from one another and hermetically bonded to an edge seal assembly therebetween. The resulting cavity between the lites is evacuated to create at least one insulating vacuum cavity within which are disposed a plurality of stand-off members to maintain separation between the lites. The edge seal assembly is preferably compliant in the longitudinal (i.e., edgewise) direction to allow longitudinal relative motion between the two lites (e.g., from thermal expansion). The longitudinal compliance may be obtained by imprinting a three-dimensional pattern into the edge seal material. The edge seal assembly is preferably bonded to the lites with a first bond portion that is hermetic and a second bond portion that is load-resistant. Methods for producing VIGUs and/or compliant edge seal assemblies and VIGU and edge seal apparatus are disclosed.

Francis, William H.↗

The Implementation of Satellite Attitude Control System Software Using Object Oriented Design

NASA established the Small Explorer (SNMX) program in 1988 to provide frequent opportunities for highly focused and relatively inexpensive space science missions. The SMEX program has produced five satellites, three of which have been successfully launched. The remaining two spacecraft are scheduled for launch within the coming year. NASA has recently developed a prototype for the next generation Small Explorer spacecraft (SMEX-Lite). This paper describes the object-oriented design (OOD) of the SMEX-Lite Attitude Control System (ACS) software. The SMEX-Lite ACS is three-axis controlled and is capable of performing sub-arc-minute pointing. This paper first describes high level requirements governing the SMEX-Lite ACS software architecture. Next, the context in which the software resides is explained. The paper describes the principles of encapsulation, inheritance, and polymorphism with respect to the implementation of an ACS software system. This paper will also discuss the design of several ACS software components. Specifically, object-oriented designs are presented for sensor data processing, attitude determination, attitude control, and failure detection. Finally, this paper will address the establishment of the ACS Foundation Class (AFC) Library. The AFC is a large software repository, requiring a minimal amount of code modifications to produce ACS software for future projects.

Reid, W. Mark↗

Final Report on the Detection of Green Monopropellants

In 2014, National Aeronautics and Space Administration (NASA) Kennedy Space Center (KSC) funded a project titled "Familiarization and Detection of Green Monopropellants" utilizing Independent Research and Technology Development (IR&TD) and Center Innovation Fund (CIF) funding. The purpose of the project was to evaluate methods of detection for ammonium dinitramide (ADN) and hydroxylammonium nitrate (HAN). An Engineering Services Contract (ESC) task order was created with the scope of evaluation of several methods of detecting ADN- and HAN-based propellants, as well as development of methods for detection. Detection methods include developed methods such as colorimetric indicating absorbent socks, and commercial-off-the- shelf (COTS) units for ammonia detection. An additional goal of the task order was for ESC to become familiar with ADN's and HAN's material properties and material compatibility. Two approaches were initially investigated as possible methods for the detection of HAN (or AFM315E) and ADN (or LMP-103S). These approaches were colorimetric analysis and instrumentation-based COTS vapor sensors utilization. Initial testing showed that the relatively non-existent vapor pressure of the AF-M315E (of which HAN is a major component) propellant would make the use of COTS sensors difficult for real-time area monitoring of HAN; a small response was detected through the use of active COTS sensors, including the RAE Systems MultiRAE Lite and Drager X-act (registered) 5000, but the levels detected were below the threshold limit value for the toxic gas ammonia. Therefore, a detection system ased upon a colorimetric indicator impregnated into an absorbent material was developed. Preliminary analysis (ESC-245-FDG-001) identified a particularly outstanding candidate as a colorimetric indicator for the detection of the presence of AF-M315E in the form of a Methyl Red (Basic) indicator. Materials impregnated with this indicator exhibit significant color change and the materials are not susceptible to interference from exposure to water or carbon dioxide. The completed detection system for HAN/AF-M315E consists of absorbent socks packed with Fisher Universal Spill Absorbent capable of absorbing and containing any propellant spills that they come into contact with along with indicating wipes. The absorbent socks are also chemically treated with a Methyl Red (Basic) indicator solution to provide the end user with a visual indication that a leak has occurred and proper protective precautions must be undertaken. An added benefit of this detection system is that the absorbent socks should neutralize/absorb any commodity that it comes into contact with (until saturation is reached). Additional adsorbent socks can be deployed until a color change is not seen, indicating that the HAN/AF-M315E contamination has been contained. The indicating wipes provide the user the opportunity to wipe surfaces to determine if there is any HAN/AF-M315E or HAN/AFM315E residue present. The wipes should allow the detection of fuel levels that may be too small to detect with the absorbent socks. The development of a detection system for the ADN/LMP-103S focused on the use of various COTS sensors used as real-time area monitoring devices and personal dosimeters. These COTS based sensor systems were of several different types, including both actively pumped and diffusion-based passive systems, as well as a "rope"-type chemical sensing cable. The results highlighted some of the major differences between the two monopropellants undergoing evaluation. Unlike HAN, ADN (which is the major constituent of LMP-103S) exhibits a much more volatile nature in comparison to AF-M315E. In fact, testing showed that a large percentage of the fuel was lost during the sampling measurement (greater than 10 percent by mass); although this testing cannot tell if the volatile component is the ADN itself or another component of the monopropellant solution. Not surprisingly, all four of the procured vapor-based COTS sensors showed positive results when exposed to solutions of the LMP-103S (ESC-245-FDG-002). The completed detection system for ADN/LMP-103S consists of a combination of two of the tested COTS sensor systems, the RAE Systems MultiRAE Lite and the BW Technologies GasAlert Extreme. These systems are meant to be used in conjunction with one another, which allows for the end-user to have both real-time area monitoring (MultiRAE Lite) as well as a personal dosimeter device (GasAlert Extreme) which can be worn as additional personal protective equipment. An stainless steel extension wand was fabricated and included in the detection system for the MultiRAE Lite to allow for more remote sensing, and connects via the active pumping inlet of the sensor. As stated, the final results of this testing resulted in the production of two "kits" which can be used for the detection of HAN/AF-M315E and ADN/LMP-103s (ESC-245-FDG-003).

Detection↗

Efficient assembly of triple pane insulating glass units

This invention describes a process flow and method to assemble triple IG units without contaminating the center glass lite. A non-contact vacuum pad is used to lift a glass lite off from a horizontal or vertical support that conveys it from a glass washer to an assembly station. Each of multiple pads has a capacity to lift approximately seven to ten pounds. Use of multiple pads per glass sheet or lite allows lites having dimensions up to 70 by 100 inches (assuming glass thickness of one quarter inch) to be assembled.

Briese, William A.↗

Registration station for assembling insulating glass windows

An insulating glass unit (IGU) assembly line comprising a registration station capable of interleaving double and triple pane IGUs in accordance with an IOU production schedule. Visual indicators or prompts instruct operators at the assembly line in configuring a sequence of IGUs. Triple pane IGUs are assembled with minimal contamination of a center glass lite. A non-contact Bernoulli pad is used to lift a glass lite off from a horizontal or vertical support that conveys it from a glass washer to the registration station. Each of multiple pads has a capacity to lift approximately seven to ten pounds. Use of multiple pads per glass sheet or lite allows lites having dimensions up to 70 by 100 inches (assuming glass thickness of one quarter inch) to be assembled.

42 ENGINEERING↗

Guidelines for Determining the Load Resistance of Thin-Glass Triple-Pane Insulating Glass Unit Configurations

This guideline is intended to provide information relevant to the specification of triple- pane insulating glass (IG) units where the thickness of lite number 2 (center lite) is less than or equal to the thickness of lite numbers 1 and 3. Procedures and charts are presented to determine the load resistance (LR) of common soda-lime glass thicknesses from 0.7 mm (3/128 in.) to 1.8 mm (9/128 in.) exposed to a uniform lateral load of short or long duration, for a 0.008 probability of breakage. Deflection under load, horizontal self-weight deflection, and natural frequency procedures and charts are also included to aide in the selection of glass thickness to meet manufacturing and/or loading criteria determined by the user.

42 ENGINEERING↗

Future applications of solid-state lasers for space remote sensing

This paper describes the Laser Atmospheric Sounder and Altimetry (LASA) and the Lidar In-Space Technology Experiment (LITE) projects, both of which will use solid-state lasers for remote sensing. LASA will provide long-term global measurements of aerosols and clouds in the earth's atmosphere. The LITE project is designed to demonstrate the first use of a lidar system in space, proving the technology required for future space-based lidar facilities such as LASA. A Shuttle flight experiment is currently being developed to enhance the technology and to formulate the design of the solid-state lidar system. Design diagrams of LITE and LASA facilities and their subsystems are presented.

Cox, John W.↗

Current technology applications in a future spaceborne lidar system

NASA is currently developing the Lidar In-space Technology Experiment (LITE) to demonstrate the first use of a lidar system for remote sensing of the atmosphere. LITE will serve as a testbed for evolving technologies. Carried by the Space Shuttle, it is a reusable experiment capable of many reflights with a short turn-around time. This requires that the instrument be of a modular design to facilitate any changes in science data requirements or to incorporate newer technology into the various subsystems. In addition, LITE is required to utilize proven technology and off-the-shelf products in its design. This paper will describe how the design of the instrument, from conceptual to final, must take into account these design requirements as well as those requirements and considerations inherent in a space flight environment.

Crockett, Sharon K.↗

Lidar In-space Technology Experiment: Overview and early results

The September 1994 Shuttle flight of the Lidar In-space Technology Experiment (LITE) brought to fruition 10 years of effort at NASA's Langley Research Center where it was built. Being the first flight of a spaceborne lidar to measure atmospheric constituents and parameters and surface properties, it culminates the efforts of many worldwide over the last 20 years to usher in this new remote sensing technique from space. This paper will describe the LITE instrument, the in-orbit performance, and initial results. In addition, the global correlative measurements program will be outlined which involved 60 groups in 20 countries who made various simultaneous ground-based or aircraft measurements as LITE flew overhead.

McCormick, M. Patrick↗

Validation of Saharan Dust Layer Characteristics with Lidar Observations

Lidar backscattering profiles available from the LITE data set have been used to estimate the optical depths of the Saharan dust layer over West Africa and E. Atlantic regions, in the context of validating the 3-D conceptual model of the Saharan dust plume proposed by Karyampudi and Carlson. The aerosol extinction profiles and optical depths were retrieved from LITE using the Fernald et al. (1972) method. An extinction-to-backscattering ratio, S(sub a), of 25 was selected for optical depth calculations. The spatial analysis of total column and Saharan dust layer optical depths show higher optical depths over W. Africa that decrease westward over E. Atlantic. The higher optical depths over W. Africa, in general, are associated with heavy dust being raised from the surface in dust source regions. Rapid depletion of these heavy dust particles, perhaps due to sedimentation, appear to decrease the dust loading within the dust layer as the plume leaves the west African continent. Higher optical depths are generally confined to the southern edge of the dust layer, where the middle level jet appears to transport the heavy dust concentrations that tend to mix downward from vertical mixing associated with the strong vertical shears underneath the middle jet. Thus, LITE measurements although, in general, validate the Saharan dust plume conceptual model, show maximum values of optical depths near the southern edge of the dust plume over the E. Atlantic region instead of near the center of the dust plume as described in the conceptual model.

Karyampudi, V. Mohan↗

The Implementation of Satellite Control System Software Using Object Oriented Design

NASA established the Small Explorer (SMEX) program in 1988 to provide frequent opportunities for highly focused and relatively inexpensive space science missions that can be launched into low earth orbit by small expendable vehicles. The development schedule for each SMEX spacecraft was three years from start to launch. The SMEX program has produced five satellites; Solar Anomalous and Magnetospheric Particle Explorer (SAMPEX), Fast Auroral Snapshot Explorer (FAST), Submillimeter Wave Astronomy Satellite (SWAS), Transition Region and Coronal Explorer (TRACE) and Wide-Field Infrared Explorer (WIRE). SAMPEX and FAST are on-orbit, TRACE is scheduled to be launched in April of 1998, WIRE is scheduled to be launched in September of 1998, and SWAS is scheduled to be launched in January of 1999. In each of these missions, the Attitude Control System (ACS) software was written using a modular procedural design. Current program goals require complete spacecraft development within 18 months. This requirement has increased pressure to write reusable flight software. Object-Oriented Design (OOD) offers the constructs for developing an application that only needs modification for mission unique requirements. This paper describes the OOD that was used to develop the SMEX-Lite ACS software. The SMEX-Lite ACS is three-axis controlled, momentum stabilized, and is capable of performing sub-arc-minute pointing. The paper first describes the high level requirements which governed the architecture of the SMEX-Lite ACS software. Next, the context in which the software resides is explained. The paper describes the benefits of encapsulation, inheritance and polymorphism with respect to the implementation of an ACS software system. This paper will discuss the design of several software components that comprise the ACS software. Specifically, Object-Oriented designs are presented for sensor data processing, attitude control, attitude determination and failure detection. The paper addresses the benefits of the OOD versus a conventional procedural design. The final discussion in this paper will address the establishment of the ACS Foundation Class (AFC) Library. The AFC is a large software repository, requiring a minimal amount of code modifications to produce ACS software for future projects, saving production time and costs.

Anderson, Mark O.↗

Development of Extravehicular Visor Assembly (EVVA)

For the next generation of NASA's space suits, being able to enable an architecture for microgravity and planetary capabilities is required. To support these future missions, we will need exemplary support hardware to be designed, such as a new extravehicular visor assembly (EVVA). This EVVA will carry out its heritage mission of protecting the astronauts' eyes from harmful radiation, giving needed shade, and providing thermal protection, while also incorporating new designs that maximize overhead visibility and incorporate new technology. It will be designed to adapt with xEMU lite, a next-generation suit architecture Completed market research and literature reviews center dotSet up a NASA@Workchallenge "Incorporating Active TintableElectronic Coatings into Next Generation Space Suit Visor." center dotContacted Boeing and AlphaMicron to understand COTS solutions on the market and how they could be applied to the space suit design. oFound that there are many advantages to an active coating because of reduced mechanisms, an inherent dust tolerant design, and auto-sense capabilities. However, the COTS designs are not currently compatible with the xEMU lite form factor, the space environment, and the xEMU lite power requirement. COTS designs can also fail in the off/transparent state. center dotPursuing low TRL funding sources for future development for exploration EVA space suit Boeing 787

Davis, Kristine↗

Mirror Design Study for a Segmented HabEx System

NASA is exploring telescope and mirror technology options to meet the demanding science goals of the proposed HabEx space telescope. A key priority for the HabEx mission concept would be to leverage affordable telescope solutions that can meet challenging telescope performance requirements with a demanding program timeline. The baseline approach for HabEx is to use an unobscured, monolithic primary mirror with a coronagraph to optimize system performance. NASA is performing an initial study to investigate the feasibility of a HabEx Lite concept which would not leverage a coronagraph and would therefore, have lower exoEarth yield as a consequence, but could provide system mass, cost, and schedule advantages. The HabEx Lite concept leverages replicated, ULE® mirror segments to provide an attractive, alternative telescope architecture to meet the HabEx threshold mission needs. We present the initial mirror design and performance assessment for the HabEx Lite concept.

Schulz, Kevin↗

Battery State of Health Estimator: Cooperative Research and Development Final Report

NREL has developed a software tool to enable Renewance to estimate the degradation of batteries from basic information such as the type of battery and the application of that battery during its first life, so that used batteries may be evaluated for potential repurposing at low cost. This software tool utilizes NREL's BLAST-Lite battery degradation modeling code, which was updated with additional models for commercially produced lithium-ion batteries as a part of this CRADA. The software tool enables users to input details such as battery type and application so that lifetime estimates can be made without any programming or expert battery knowledge. The application input loads in saved values for parameters such as cycles per year, depth-of-discharge, and other battery operating parameters from a file defined by Renewance. These parameters may be modified to refine simulations for specific batteries. The software tool also incorporates a degradation model optimization tool, whereby existing battery degradation models may be tuned according to measured battery health. This ensures that new models still predict degradation behaviors expected from a certain battery chemistry, but with the overall degradation rate tuned to a specific battery make and model. The new model can then be saved for estimating the degradation of other similar batteries. An additional task was planned to utilize machine-learning to enable battery health diagnosis from rapid EIS measurements to accelerate the screening of used batteries. This task was not completed due to lack of available data for training a machine-learning model. CRADA benefit to DOE, Participant, and US Taxpayer: Further development of open-source software tool BLAST-Lite for predicting the lifetime of commercially produced Lithium-ion batteries (NREL SWR-22-69).

25 ENERGY STORAGE↗

SIM PlanetQuest: Progress Report

SIM PlanetQuest, a micro-arcsecond astrometry space mission, has been impacted by significant changes in NASA priorities over the last two years, resulting in the mission being indefinitely delayed. The SIM team has responded by investigating alternative mission concepts based upon completed SIM technology. Several alternative mission concepts have been identified, ranging from a planets-only concept, to versions of SIM, called SIM-Lite, that still address the full breadth of SIM science envisioned by two previous National Academy Astrophysics Decadal Surveys but with lower precision and reduced throughput. These mission concepts, Planet Hunter and SIM-Lite, are significantly more affordable and may fit into a nearer-term future scenario than the full SIM PlanetQuest would. This paper describes the current state of the SIM project, including its design and technology, and the alternative mission concepts for the use of these designs and technology.

SIM-Lite↗

Tuned Reactivity at the Lithium Metal–Argyrodite Solid State Electrolyte Interphase

Thin intermetallic Li 2 Te–LiTe 3 bilayer (0.75 µm) derived from 2D tellurene stabilizes the solid electrolyte interphase (SEI) of lithium metal and argyrodite (LPSCl, Li 6 PS 5 Cl) solid-state electrolyte (SSE). Tellurene is loaded onto a standard battery separator and reacted with lithium through single-pass mechanical rolling or transferred directly to SSE surface by pressing. State-of-the-art electrochemical performance is achieved, e.g., symmetric cell stable for 300 cycles (1800 h) at 1 mA cm -2 and 3 mAh cm -2 (25% DOD, 60 µm foil). Cryo-stage focused ion beam (Cryo-FIB) sectioning and Raman mapping demonstrate that the Li 2 Te–LiTe 3 bilayer impedes SSE decomposition. The unmodified Li–LPSCl interphase is electrochemically unstable with a geometrically heterogeneous reduction decomposition reaction front that extends deep into the SSE. Decomposition drives voiding in Li metal due to its high flux to the reaction front, as well as voiding in the SSE due to the associated volume changes. Analysis of cycled SSE found no evidence for pristine (unreacted) lithium metal filaments/dendrites, implying failure driven by decomposition phases with sufficient electrical conductivity that span electrolyte thickness. In conclusion, DFT calculations clarify thermodynamic stability, interfacial adhesion, and electronic transport properties of interphases, while mesoscale modeling examines interrelations between reaction front heterogeneity (SEI heterogeneity), current distribution, and localized chemo-mechanical stresses.

25 ENERGY STORAGE↗

White-Rabbit-Disciplined FPGA Readout for Fermilab Timing Events

Fermilab's accelerator timing links broadcast short event codes to thousands of devices at once, but the links themselves carry no absolute notion of time; that comes separately from a White Rabbit reference. This work builds the piece that ties the two together on a single board. On a Xilinx Kria KR260 (Zynq UltraScale+), the programmable logic decodes a real Fermilab TCLK link, stamps every event with an absolute White-Rabbit \{sec, ns\} UTC time, and reads the timestamped stream out over AXI4-Lite; a thin Linux process on the same die publishes each event into a Redis stream on the control network. To exercise the full chain on one board, the decoded events are re-encoded as gigabit ACLK, transmitted out an SFP+ optical port, looped back over a short fiber jumper, and decoded again on the same timeline, and are additionally mirrored as an ACLK-Lite Manchester waveform for benchtop probing. Across sustained, multi-day testing against real Fermilab TCLK, the pipeline has decoded, timestamped, and published hundreds of millions of events with practically zero loss, and folding the timestamped stream on the 60-second accelerator supercycle recovers the machine's periodic structure directly from the published data.

Rossel, Jacob [Fermilab; UC, Berkeley (main)] (ORC↗

Possible Presence of a Third Body in the Kepler K2 Variable EPIC 202073314

We report the presence of an unseen third-body companion in a low-mass-ratio deep contact binary system Kepler K2 EPIC 202073314 as seen by the presence of the light time effect (LITE) on the O–C diagram. The system is found to be exhibiting an increasing period trend along with a sinusoidal behavior of the O–C residuals owing to the LITE variations. The residuals are modeled initially assuming a circular orbit to obtain a third-body orbital period of ∼9.75 years. We further performed a rigorous analysis by allowing the eccentricity to vary, which led to a third-body orbital period of ∼8.66 years with e {sub 3} = 0.51. We also report the photometric study of this variable. The system is found to have a mass ratio of ∼0.15 with an inclination of ∼77°. Monte-Carlo simulations were performed to verify the consistency of the obtained photometric solution. The system is considered to be in significant geometrical contact as seen by the high fill-out factor of ∼57%. Magnetic inactivity of the system is understood in terms of the absence of O’ Connell effect and lack of fill-in effect in the Hα spectral line. The dynamical state of the system is discussed in terms of the Hut’s stability criteria (((J{sub spin})/(J{sub orb}))=(1/3)) as the low-mass and high fill-out factor configuration of the system makes it a promising candidate in the context of stellar mergers. Assuming conservative mass transfer, the system is expected to meet the critical mass ratio of ∼0.07–0.09 in ∼10{sup 6} years.

79 ASTRONOMY AND ASTROPHYSICS↗