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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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NASA NTRS1995

The Development and Use of a Flight Optimization System Model of a C-130E Transport Aircraft

The Systems Analysis Branch at NASA Langley Research Center conducts a variety of aircraft design and analyses studies. These studies include the prediction of characteristics of a particular conceptual design, analyses of designs that already exist, and assessments of the impact of technology on current and future aircraft. The FLight OPtimization System (FLOPS) is a tool used for aircraft systems analysis and design. A baseline input model of a Lockheed C-130E was generated for the Flight Optimization System. This FLOPS model can be used to conduct design-trade studies and technology impact assessments. The input model was generated using standard input data such as basic geometries and mission specifications. All of the other data needed to determine the airplane performance is computed internally by FLOPS. The model was then calibrated to reproduce the actual airplane performance from flight test data. This allows a systems analyzer to change a specific item of geometry or mission definition in the FLOPS input file and evaluate the resulting change in performance from the output file. The baseline model of the C-130E was used to analyze the effects of implementing upper wing surface blowing on the airplane. This involved removing the turboprop engines that were on the C-130E and replacing them with turbofan engines. An investigation of the improvements in airplane performance with the new engines could be conducted within the Flight Optimization System. Although a thorough analysis was not completed, the impact of this change on basic mission performance was investigated.

Desch, Jeremy D.↗

NASA NTRS2002

Synthesizing Monitors for Safety Properties

The problem of testing a linear temporal logic (LTL) formula on a finite execution trace of events, generated by an executing program, occurs naturally in time analysis of software. An algorithm which takes a past time LTL formula and generates an efficient dynamic programming algorithm is presented. The generated algorithm tests whether the formula is satisfied by a finite trace of events given as input and runs in linear time, its constant depending on the size of the LTL formula. The memory needed is constant, also depending on the size of the formula. Further optimizations of the algorithm are suggested. Past time operators suitable for writing succinct specifications axe introduced and shown definitionally equivalent to the standard operators. This work is part of the PathExplorer project, the objective of which it is to construct a flexible framework for monitoring and analyzing program executions.

Havelund, Klaus↗

NASA NTRS1988

Balance System

TherEx Inc.'s AT-1 Computerized Ataxiameter precisely evaluates posture and balance disturbances that commonly accompany neurological and musculoskeletal disorders. Complete system includes two-strain gauged footplates, signal conditioning circuitry, a computer monitor, printer and a stand-alone tiltable balance platform. AT-1 serves as assessment tool, treatment monitor, and rehabilitation training device. It allows clinician to document quantitatively the outcome of treatment and analyze data over time to develop outcome standards for several classifications of patients. It can evaluate specifically the effects of surgery, drug treatment, physical therapy or prosthetic devices.

Source record↗

NASA NTRS2004

Multibeam Phased Array Antennas

In this study, a new architecture for Ka-band multi-beam arrays was developed and demonstrated experimentally. The goal of the investigation was to demonstrate a new architecture that has the potential of reducing the cost as compared to standard expensive phased array technology. The goals of this specific part of the project, as stated in the yearly statement of work in the original proposal are: 1. Investigate bounds on performance of multi-beam lens arrays in terms of beamwidths, volume (size), isolation between beams, number of simultaneous beams, etc. 2. Design a small-scale array to demonstrate the principle. The array will be designed for operation around 3OGHz (Ka-band), with two 10-degree beamwidth beams. 3. Investigate most appropriate way to accomplish fine-tuning of the beam pointing within 5 degrees around the main beam pointing angle.

Popovic, Zoya↗

NASA NTRS2006

A Multi-mission Event-Driven Component-Based System for Support of Flight Software Development, ATLO, and Operations first used by the Mars Science Laboratory (MSL) Project

This paper details an architectural description of the Mission Data Processing and Control System (MPCS), an event-driven, multi-mission ground data processing components providing uplink, downlink, and data management capabilities which will support the Mars Science Laboratory (MSL) project as its first target mission. MPCS is developed based on a set of small reusable components, implemented in Java, each designed with a specific function and well-defined interfaces. An industry standard messaging bus is used to transfer information among system components. Components generate standard messages which are used to capture system information, as well as triggers to support the event-driven architecture of the system. Event-driven systems are highly desirable for processing high-rate telemetry (science and engineering) data, and for supporting automation for many mission operations processes.

Mission Data Processing and Control System (MPCS)↗

NASA NTRS1994

Transesophageal Echocardiography and Contrast-TCD in the Detection of a Patent Foramen Ovale: Experience with 111 Patients

Patent foramen ovale (PFO) is increasingly recognized in association with cryptogenic stroke. Using transesophageal echocardiography (TEE) and transcranial Doppler sonography with ultrasonic contrast medium contrast-(TCD), we evaluated the frequency of a PFO as the fundamental condition of paradoxical embolism in 111 patients after cerebral ischemia. There was a right-left shunt in 50 patients (45%) with TEE. In 31 of 40 patients with stroke of unknown etiology, a PFO was the only detectable finding associated with cerebral ischemia. Using TEE as he "gold standard," the sensitivity of contrast-TCD was 91.3%, specificity 93.8%, and the overall accuracy 92.8%. contrast-TCD failed to detect a right-left shunt in four patients, but there were four other patients with negative TEE and positive contrast-TCD. We conclude that contrast-TCD is a highly sensitive method for detecting a right-left shunt. Its advantages are low cost, its ability to detect single contrast-medium embolism, and control of the Valsalva maneuver by observing the decrease of cerebral blood flow. Evidence of PFO in cryptogenic stroke should prompt a search for a subclinical venous thrombosis as the embolic source.

Klotzsch, Christof↗

NASA NTRS2005

Simultaneous Conoscopic Holography and Raman Spectroscopy

A new instrument was developed for chemical characterization of surfaces that combines the analytical power of Raman spectroscopy with the three-dimensional topographic information provided by conoscopic holography. The figure schematically depicts the proposed hybrid instrument. The output of the conoscopic holographic portion of the instrument is a topographical map of the surface; the output of the Raman portion of the instrument is hyperspectral Raman data, from which the chemical and/or biological composition of the surface would be deduced. By virtue of the basic principles of design and operation of the instrument, the hyperspectral image data would be inherently spatially registered with the topographical data. In conoscopic holography, the object and reference beams of classical holography are replaced by the ordinary and extraordinary components generated by a single beam traveling through a birefringent, uniaxial crystal. In the basic conoscopic configuration, a laser light is projected onto a specimen and the resulting illuminated spot becomes a point source of diffuse light that propagates in every direction. The laser beam is rasterscanned in two dimensions (x and y) perpendicular to the beam axis (z), and at each x,y location, the pattern of interference between the ordinary and extraordinary rays is recorded. The recorded interferogram constitutes the conoscopic hologram. Of particular significance for the proposed instrument is that the conoscopic hologram contains information on the z coordinate (height) of the illuminated surface spot. Hence, a topographical map of the specimen is constructed point-by-point by rastering the laser beam in the x and y directions and correlating the x and y coordinates with the z information obtained from the interferograms. Conoscopic imaging is an established method, and conoscopic laboratory instruments for surface metrology are commercially available. In Raman spectroscopy of a surface, one measures the spectrum of laser light scattered inelastically from a laser-illuminated spot on the surface. The wavelengths of the inelastically scattered light differ from that of the incident laser beam by amounts that correspond to the energies of molecular vibrations. The resulting vibrational spectrum can be used to identify the molecules. Raman spectroscopy is a standard laboratory technique for identifying mineralogical, biological, and other specific chemical compositions.

Schramm, Harry F.↗

NASA NTRS2004

Relative-Motion Sensors and Actuators for Two Optical Tables

Optoelectronic sensors and magnetic actuators have been developed as parts of a system for controlling the relative position and attitude of two massive optical tables that float on separate standard air suspensions that attenuate ground vibrations. In the specific application for which these sensors and actuators were developed, one of the optical tables holds an optical system that mimics distant stars, while the other optical table holds a test article that simulates a spaceborne stellar interferometer that would be used to observe the stars. The control system is designed to suppress relative motion of the tables or, on demand, to impose controlled relative motion between the tables. The control system includes a sensor system that detects relative motion of the tables in six independent degrees of freedom and a drive system that can apply force to the star-simulator table in the six degrees of freedom. The sensor system includes (1) a set of laser heterodyne gauges and (2) a set of four diode lasers on the star-simulator table, each aimed at one of four quadrant photodiodes at nominal corresponding positions on the test-article table. The heterodyne gauges are used to measure relative displacements along the x axis.

Gursel, Yekta↗

NASA NTRS2012

ISS Potable Water Quality for Expeditions 26 through 30

International Space Station (ISS) Expeditions 26-30 spanned a 16-month period beginning in November of 2010 wherein the final 3 flights of the Space Shuttle program finished ISS construction and delivered supplies to support the post-shuttle era of station operations. Expedition crews relied on several sources of potable water during this period, including water recovered from urine distillate and humidity condensate by the U.S. water processor, water regenerated from humidity condensate by the Russian water recovery system, and Russian ground-supplied potable water. Potable water samples collected during Expeditions 26-30 were returned on Shuttle flights STS-133 (ULF5), STS-134 (ULF6), and STS-135 (ULF7), as well as Soyuz flights 24-27. The chemical quality of the ISS potable water supplies continued to be verified by the Johnson Space Center s Water and Food Analytical Laboratory (WAFAL) via analyses of returned water samples. This paper presents the chemical analysis results for water samples returned from Expeditions 26-30 and discusses their compliance with ISS potable water standards. The presence or absence of dimethylsilanediol (DMSD) is specifically addressed, since DMSD was identified as the primary cause of the temporary rise and fall in total organic carbon of the U.S. product water that occurred in the summer of 2010.

Straub, John E., II↗

NASA NTRS2012

Standardization of the Definitions of Vertical Resolution and Uncertainty in the NDACC-archived Ozone and Temperature Lidar Measurements

The international Network for the Detection of Atmospheric Composition Change (NDACC) is a global network of high-quality, remote-sensing research stations for observing and understanding the physical and chemical state of the Earth atmosphere. As part of NDACC, over 20 ground-based lidar instruments are dedicated to the long-term monitoring of atmospheric composition and to the validation of space-borne measurements of the atmosphere from environmental satellites such as Aura and ENVISAT. One caveat of large networks such as NDACC is the difficulty to archive measurement and analysis information consistently from one research group (or instrument) to another [1][2][3]. Yet the need for consistent definitions has strengthened as datasets of various origin (e.g., satellite and ground-based) are increasingly used for intercomparisons, validation, and ingested together in global assimilation systems.In the framework of the 2010 Call for Proposals by the International Space Science Institute (ISSI) located in Bern, Switzerland, a Team of lidar experts was created to address existing issues in three critical aspects of the NDACC lidar ozone and temperature data retrievals: signal filtering and the vertical filtering of the retrieved profiles, the quantification and propagation of the uncertainties, and the consistent definition and reporting of filtering and uncertainties in the NDACC- archived products. Additional experts from the satellite and global data standards communities complement the team to help address issues specific to the latter aspect.

Detection of Atmospheric Composition Change (NDACC↗

NASA NTRS2013

BOK-Printed Electronics

The use of printed electronics technologies (PETs), 2D or 3D printing approaches either by conventional electronic fabrication or by rapid graphic printing of organic or nonorganic electronic devices on various small or large rigid or flexible substrates, is projected to grow exponentially in commercial industry. This has provided an opportunity to determine whether or not PETs could be applicable for low volume and high-reliability applications. This report presents a summary of literature surveyed and provides a body of knowledge (BOK) gathered on the current status of organic and printed electronics technologies. It reviews three key industry roadmaps- on this subject-OE-A, ITRS, and iNEMI-each with a different name identification for this emerging technology. This followed by a brief review of the status of the industry on standard development for this technology, including IEEE and IPC specifications. The report concludes with key technologies and applications and provides a technology hierarchy similar to those of conventional microelectronics for electronics packaging. Understanding key technology roadmaps, parameters, and applications is important when judicially selecting and narrowing the follow-up of new and emerging applicable technologies for evaluation, as well as the low risk insertion of organic, large area, and printed electronics.

Ghaffarian, Reza↗

NASA NTRS2016

Managing Sustainable Data Infrastructures: The Gestalt of EOSDIS

EOSDIS epitomizes a System of Systems, whose many varied and distributed parts are integrated into a single, highly functional organized science data system. A distributed architecture was adopted to ensure discipline-specific support for the science data, while also leveraging standards and establishing policies and tools to enable interdisciplinary research, and analysis across multiple scientific instruments. The EOSDIS is composed of system elements such as geographically distributed archive centers used to manage the stewardship of data. The infrastructure consists of underlying capabilities connections that enable the primary system elements to function together. For example, one key infrastructure component is the common metadata repository, which enables discovery of all data within the EOSDIS system. EOSDIS employs processes and standards to ensure partners can work together effectively, and provide coherent services to users.

remote sensing↗

NASA NTRS2017

Adjoint-Based Mesh Adaptation for the Sonic Boom Signature Loudness

The mesh adaptation functionality of FUN3D is utilized to obtain a mesh optimized to calculate sonic boom ground signature loudness. During this process, the coupling between the discrete-adjoints of the computational fluid dynamics tool FUN3D and the atmospheric propagation tool sBOOM is exploited to form the error estimate. This new mesh adaptation methodology will allow generation of suitable meshes adapted to reduce the estimated errors in the ground loudness, which is an optimization metric employed in supersonic aircraft design. This new output-based adaptation could allow new insights into meshing for sonic boom analysis and design, and complements existing output-based adaptation techniques such as adaptation to reduce estimated errors in off-body pressure functional. This effort could also have implications for other coupled multidisciplinary adjoint capabilities (e.g., aeroelasticity) as well as inclusion of propagation specific parameters such as prevailing winds or non-standard atmospheric conditions. Results are discussed in the context of existing methods and appropriate conclusions are drawn as to the efficacy and efficiency of the developed capability.

Rallabhandi, Sriram K.↗

NASA NTRS1995

A Multi-Mission Space Avionics Architecture

As the budget for the space industry is dwindling, a reusable avionics architecture applicable across multiple missions is urgently needed to reduce the development and production costs of flight projects. This paper presents a multi-mission avionics architecture which employs interface standards extensively, sot hat avionics systems can be built rapidly by assembling subsystems and instruments in a plug-and-play manner. The key feature of this architecture is a "backbone" standard parallel bus which can accommodate various standard interfaces through a repertoire of I/O modules. Hence, specific ;mission requirements can be met by selecting and integrating the appropriate subsystems and instruments into the system. This architecture can also adopt different "backbone" buses, implement redundant processors, and support distributed processing. An example of the architecture using the MOPS6000 from the Southwest Research Institute is also described. Experiments will be done in the Flight System Testbed (FST) of the Jet Propulsion Laboratory to benchmark the MOPS6000 and to demonstrate its multi-mission capability.

Avionics↗

NASA NTRS2017

Comprehensive Measurement of Microbial Burden in Nutrient-Deprived Cleanrooms

Spacecraft surfaces that are destined to land on potential life-harboring celestial bodies are required to be rigorously cleaned and continuously monitored for spore bioburden as a proxy for spacecraft cleanliness. The NASA standard spore assay (NSA), used for spacecraft bioburden estimates, specifically measures spores that are cultivable, aerobic, resistant to heat shock, and grow at 30˚C in a nutrient-rich medium. Since the vast majority of microorganisms cannot be cultivated using the NSA assay, it is necessary to utilize state-of-the art molecular techniques to better understand the presence of all viable microorganisms, not just those measured with the NSA. In this study, the nutrient-deprived low biomass cleanrooms, where spacecraft are assembled, were used as a surrogate to spacecraft surfaces to measure the ratio of NSA spores in relation to the total viable microorganism population to compare with a 2006 space studies report that estimates that for every 1 spore there is approximately 50,000 viable organisms. Ninety-eight surface wipe samples were collected from the spacecraft assembly facility (SAF) cleanroom at the Jet Propulsion Laboratory (JPL) over a 6-month period. The samples were processed and analyzed using classical microbiology along with molecular assays. Traditional microbiology plating methods were used to determine the cultivable bacterial, fungal, and spore populations. Molecular assays were used to determine the total organisms (TO, dead and live) and the viable organisms (VO, live). The TO was measured using adenine triphosphate (ATP) and quantitative polymerase chain reaction (qPCR) assays. The VO was measured using internal ATP, propidium monoazide (PMA)-qPCR, and flow cytometry (after staining for viable microorganisms) assays. Based on the results, it was possible to establish a ratio between spore counts and VO for each viability assay. The ATP based spore to VO ratio ranged from 149 – 746 and the bacterial PMA-qPCR assay based ratio ranged from 314 – 1491 VO. The most conservative estimate came from FACS, which estimated the ratio to be 12,091 VO per 1 NSA spore. Since archaeal (<1%) and fungal (~2%) populations were negligible, the spore to VO ratios were based on bacterial population estimates. The most conservative ratio from this study can be used as a replacement for the SSB estimate on nutrient-deprived (oligotrophic) desiccated spacecraft surfaces, to estimate the VO from NSA measurements without utilizing state-of-the art molecular methods that are costly and require more biomass than is typically found of spacecraft surfaces.

Venkateswaran, Kasthuri↗

NASA NTRSDate not supplied

Applying Formal Methods to Safety-Critical Systems

How do you know a proof is correct? Traditionally, mathematical proofs are socially verified – at least one human, following a set of implicit rules of natural language and logic, determines if the proof is believable. If the proof becomes overly tedious and/or is essential to some safety- or mission-critical application, it becomes necessary to determine the soundness to a higher standard. 'Formal methods' refer to mathematically rigorous techniques and tools that enable specification, design, and verification of hardware and software systems. The specification used in formal methods are statements in a mathematical logic while the formal verifications are deductions in that logic. Formal methods can be difficult or time/resource intensive, but offer a higher level of assurance than standard verification through testing or handwritten proofs. This talk will introduce formal methods, motivated by applications of interest to NASA, including uncrewed aircraft operations in the national airspace, urban air environments, and wildfire areas. The audience will be given a crash course in mechanically verified proofs in the Prototype Verification System (PVS), an interactive theorem prover.

Formal Methods↗

NASA NTRS2003

Standards-and Component-Based Mission Operations Architecture at NASA's Goddard Space Flight Center

NASA Goddard Space Flight Center (GSFC) manages many of NASA s earth and space science satellite missions. A wide variety of commercial products and GSFC-developed software components are typically integrated into a unique system configuration for each mission. Independent development of the many mission operations center systems has led to systems that are expensive to integrate, difficult to infuse with new capabilities developed for other programs, and cumbersome to maintain. This traditional approach becomes even more problematic as NASA moves towards satellite constellations, new operations concepts, and even further budgets reductions. The GSFC Mission Services Evolution Center (GMSEC) is creating a new architecture for future missions at GSFC. Instead of selecting the best-in-class components and creating a standard control center system, GMSEC is developing component interface standards so that multiple products can plug-and-play into the configuration. Missions can then select the best components based on the merits of the product and not simply based on recent integration history at NASA. The GMSEC system utilizes a publish/subscribe information bus and standard XML-based key message interfaces. Functional components can either match directly to the interface standard, or adapters can be developed to match the product's interface to the GMSEC standard with out impacting the source product. Applications Program Interfaces (API's) are being developed to isolate the underlying middleware from the applications software and to allow the middleware product to be switched if necessary. Interface Control Documents (ICDs) between each pair of communicating components is replaced by a single message/API specification document. New applications must simply match to the information bus standards and need not worry about all of the other applications in the system. For legacy software, adapters can be developed to facilitate communications between the application and the information bus. As the approach has matured, it has become apparent that it can provide innovative solutions to some of the multi-satellite challenges facing GSFC.

Smith, Danford↗

NASA NTRS2021

Draft LunaNet Interoperability Specification

Under the guidance of NASA’s Space Communication and Navigation (SCaN) program, this document, along with its companion documents, LunaNet Services Requirements Document (TBD) and the LunaNet Concept of Operations and Architecture (TBD), provides the basis for a comprehensive set of requirements for operation of a lunar communications and navigation network capable of interoperating with other networks compliant with the Lunar Network (LunaNet) for services to the human exploration, lunar science, and space technology missions. LunaNet will start with a simple architecture of a few nodes to meet the needs of the early missions and evolve to meet the growing needs of a sustained lunar presence. All relay network services are not expected to be met by a single spacecraft platform, or node. The expectation is that the needs of NASA, its partners and other users will be met through a combination of interoperable systems provided by NASA, international partners, and commercial providers. Interoperability across this network-of-networks can be achieved through negotiation of mutually-agreed-upon standards that will be reflected in this document and in the specifications defined by other participants in the combined, cooperative lunar network.

LunaNet↗