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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 NTRS2016

A Survey of Cost Estimating Methodologies for Distributed Spacecraft Missions

Satellite constellations and Distributed Spacecraft Mission (DSM) architectures offer unique benefits to Earth observation scientists and unique challenges to cost estimators. The Cost and Risk (CR) module of the Tradespace Analysis Tool for Constellations (TAT-C) being developed by NASA Goddard seeks to address some of these challenges by providing a new approach to cost modeling, which aggregates existing Cost Estimating Relationships (CER) from respected sources, cost estimating best practices, and data from existing and proposed satellite designs. Cost estimation through this tool is approached from two perspectives: parametric cost estimating relationships and analogous cost estimation techniques. The dual approach utilized within the TAT-C CR module is intended to address prevailing concerns regarding early design stage cost estimates, and offer increased transparency and fidelity by offering two preliminary perspectives on mission cost. This work outlines the existing cost model, details assumptions built into the model, and explains what measures have been taken to address the particular challenges of constellation cost estimating. The risk estimation portion of the TAT-C CR module is still in development and will be presented in future work. The cost estimate produced by the CR module is not intended to be an exact mission valuation, but rather a comparative tool to assist in the exploration of the constellation design tradespace. Previous work has noted that estimating the cost of satellite constellations is difficult given that no comprehensive model for constellation cost estimation has yet been developed, and as such, quantitative assessment of multiple spacecraft missions has many remaining areas of uncertainty. By incorporating well-established CERs with preliminary approaches to approaching these uncertainties, the CR module offers more complete approach to constellation costing than has previously been available to mission architects or Earth scientists seeking to leverage the capabilities of multiple spacecraft working in support of a common goal.

0↗
NASA NTRS2016

A Survey of Cost Estimating Methodologies for Distributed Spacecraft Missions

Satellite constellations and Distributed Spacecraft Mission (DSM) architectures offer unique benefits to Earth observation scientists and unique challenges to cost estimators. The Cost and Risk (CR) module of the Tradespace Analysis Tool for Constellations (TAT-C) being developed by NASA Goddard seeks to address some of these challenges by providing a new approach to cost modeling, which aggregates existing Cost Estimating Relationships (CER) from respected sources, cost estimating best practices, and data from existing and proposed satellite designs. Cost estimation through this tool is approached from two perspectives: parametric cost estimating relationships and analogous cost estimation techniques. The dual approach utilized within the TAT-C CR module is intended to address prevailing concerns regarding early design stage cost estimates, and offer increased transparency and fidelity by offering two preliminary perspectives on mission cost. This work outlines the existing cost model, details assumptions built into the model, and explains what measures have been taken to address the particular challenges of constellation cost estimating. The risk estimation portion of the TAT-C CR module is still in development and will be presented in future work. The cost estimate produced by the CR module is not intended to be an exact mission valuation, but rather a comparative tool to assist in the exploration of the constellation design tradespace. Previous work has noted that estimating the cost of satellite constellations is difficult given that no comprehensive model for constellation cost estimation has yet been developed, and as such, quantitative assessment of multiple spacecraft missions has many remaining areas of uncertainty. By incorporating well-established CERs with preliminary approaches to approaching these uncertainties, the CR module offers more complete approach to constellation costing than has previously been available to mission architects or Earth scientists seeking to leverage the capabilities of multiple spacecraft working in support of a common goal.

Foreman, Veronica L.↗
NASA NTRS2016

NASA Work Breakdown Structure (WBS) Handbook

The purpose of this document is to provide program/project teams necessary instruction and guidance in the best practices for Work Breakdown Structure (WBS) and WBS dictionary development and use for project implementation and management control. This handbook can be used for all types of NASA projects and work activities including research, development, construction, test and evaluation, and operations. The products of these work efforts may be hardware, software, data, or service elements (alone or in combination). The aim of this document is to assist project teams in the development of effective work breakdown structures that provide a framework of common reference for all project elements. The WBS and WBS dictionary are effective management processes for planning, organizing, and administering NASA programs and projects. The guidance contained in this document is applicable to both in-house, NASA-led effort and contracted effort. It assists management teams from both entities in fulfilling necessary responsibilities for successful accomplishment of project cost, schedule, and technical goals. Benefits resulting from the use of an effective WBS include, but are not limited to: providing a basis for assigned project responsibilities, providing a basis for project schedule and budget development, simplifying a project by dividing the total work scope into manageable units, and providing a common reference for all project communication.

Planning↗
NASA NTRS2016

Making Interoperability Easier with NASA's Metadata Management Tool (MMT)

While the ISO-19115 collection level metadata format meets many users' needs for interoperable metadata, it can be cumbersome to create it correctly. Through the MMT's simple UI experience, metadata curators can create and edit collections which are compliant with ISO-19115 without full knowledge of the NASA Best Practices implementation of ISO-19115 format. Users are guided through the metadata creation process through a forms-based editor, complete with field information, validation hints and picklists. Once a record is completed, users can download the metadata in any of the supported formats with just 2 clicks.

metadata quality↗
NASA NTRS2016

Full-Field Reconstruction of Structural Deformations and Loads from Measured Strain Data on a Wing Using the Inverse Finite Element Method

A study was undertaken to investigate the measurement of wing deformation and internal loads using measured strain data. Future aerospace vehicle research depends on the ability to accurately measure the deformation and internal loads during ground testing and in flight. The approach uses the inverse Finite Element Method (iFEM). The iFEM is a robust, computationally efficient method that is well suited for real-time measurement of real-time structural deformation and loads. The method has been validated in previous work, but has yet to be applied to a large-scale test article. This work is in preparation for an upcoming loads test of a half-span test wing in the Flight Loads Laboratory at the National Aeronautics and Space Administration Armstrong Flight Research Center (Edwards, California). The method has been implemented into an efficient MATLAB® (The MathWorks, Inc., Natick, Massachusetts) code for testing different sensor configurations. This report discusses formulation and implementation along with the preliminary results from a representative aerospace structure. The end goal is to investigate the modeling and sensor placement approach so that the best practices can be applied to future aerospace projects.

Finite element↗
NASA NTRS2016

Goddard Earth Science Data and Information Center (GES DISC)

The GES DIS is one of 12 NASA Earth science data centers. The GES DISC vision is to enable researchers and educators maximize knowledge of the Earth by engaging in understanding their goals, and by leading the advancement of remote sensing information services in response to satisfying their goals. This presentation will describe the GES DISC approach, successes, challenges, and best practices.

data management↗
NASA NTRS2016

Streamlining the Design Tradespace for Earth Imaging Constellations

Satellite constellations and Distributed Spacecraft Mission (DSM) architectures offer unique benefits to Earth observation scientists and unique challenges to cost estimators. The Cost and Risk (CR) module of the Tradespace Analysis Tool for Constellations (TAT-C) being developed by NASA Goddard seeks to address some of these challenges by providing a new approach to cost modeling, which aggregates existing Cost Estimating Relationships (CER) from respected sources, cost estimating best practices, and data from existing and proposed satellite designs. Cost estimation through this tool is approached from two perspectives: parametric cost estimating relationships and analogous cost estimation techniques. The dual approach utilized within the TAT-C CR module is intended to address prevailing concerns regarding early design stage cost estimates, and offer increased transparency and fidelity by offering two preliminary perspectives on mission cost. This work outlines the existing cost model, details assumptions built into the model, and explains what measures have been taken to address the particular challenges of constellation cost estimating. The risk estimation portion of the TAT-C CR module is still in development and will be presented in future work. The cost estimate produced by the CR module is not intended to be an exact mission valuation, but rather a comparative tool to assist in the exploration of the constellation design tradespace. Previous work has noted that estimating the cost of satellite constellations is difficult given that no comprehensive model for constellation cost estimation has yet been developed, and as such, quantitative assessment of multiple spacecraft missions has many remaining areas of uncertainty. By incorporating well-established CERs with preliminary approaches to approaching these uncertainties, the CR module offers more complete approach to constellation costing than has previously been available to mission architects or Earth scientists seeking to leverage the capabilities of multiple spacecraft working in support of a common goal.

Science Data Processing↗
NASA NTRS2017

Preparing for Veg-04 and Veg-05: Improving Pick-And-Eat Food Capabilities for the International Space Station

The capability to grow nutritious, palatable food for crew consumption during spaceflight has the potential to provide health-promoting, bioavailable nutrients, enhance the dietary experience, and reduce launch mass as we move toward longer-duration missions. Studies of edible produce during spaceflight have been limited, leaving a significant knowledge gap in the methods required to grow safe, acceptable, nutritious crops for consumption in space. Researchers from Kennedy Space Center, Johnson Space Center, Purdue University and ORBITEC have teamed up to explore the potential for plant growth and food production on the International Space Station (ISS) and future exploration missions. Ground testing of Chinese cabbage and dwarf tomato crops under different LED lighting and fertilizer conditions is being conducted to allow for a preliminary down selection of the two best lighting recipes and the best fertilizer treatment. Two trials of Chinese cabbage and one trial on dwarf tomato have been completed in on-going ground tests. Horticultural data on crop growth and productivity and chemical data on specific nutrients have been collected and are being analyzed to allow preliminary down selection. Taste test evaluations are planned on the preliminary down selection treatments to allow a final down selection for flight testing. Microbial assessment for hazard analysis critical control points (HACCP) evaluation is also underway to enable implementation of food consumption. Following down selection flight preparation will commence for testing these crops in the Veggie vegetable-production system on the ISS. A crew questionnaire has been developed to better understand the impact of crop growth in Veggie on crew behavioral health. A single Veggie plant growth chamber is currently installed on ISS, and preparations are underway to launch a second Veggie, allowing side-by-side testing under different lighting conditions. Veg-04 will be the first mission that will use this dual-Veggie capability, where the selected cultivar of Tokyo bekana Chinese cabbage will be grown under two different red-to-blue light ratios. ORBITEC has developed custom lighting software allowing independent selection of red and blue light levels. The VEG-05 experiment will test similar light treatments using Red Robin dwarf tomato. These tests offer an opportunity to develop a pick-and-eat fresh vegetable component to the ISS food system as a first step to regular supplemental food production. Our work will help define light colors, levels, and horticultural best practices to achieve high yields of safe, nutritious leafy greens and tomatoes to supplement a space diet of prepackaged food. With this work we will continue the synergistic research to help close gaps in the human research roadmap, and enable humans to venture to Mars and beyond. This research was co-funded by the Human Research Program and Space Biology (MTL1075) in the ILSRA 2015 NRA call.

International Space Station↗
NASA NTRS2017

An Introduction to Observing System Simulation Experiments

Observing System Simulation Experiments (OSSEs) are used to estimate the potential impact of proposed new instruments and data on numerical weather prediction. OSSEs can also be used to help design new observing platforms and to investigate the behavior of data assimilation systems. A basic overview of how to design and perform an OSSE will be given, as well as best practices and pitfalls. Some examples using the OSSE framework developed at the NASA Global Modeling and Assimilation Office will be shown.

OSSE↗
NASA NTRS2017

The NASA Ames Life Sciences Data Archive: Biobanking for the Final Frontier

The NASA Ames Institutional Scientific Collection involves the Ames Life Sciences Data Archive (ALSDA) and a biospecimen repository, which are responsible for archiving information and non-human biospecimens collected from spaceflight and matching ground control experiments. The ALSDA also manages a biospecimen sharing program, performs curation and long-term storage operations, and facilitates distribution of biospecimens for research purposes via a public website (https:lsda.jsc.nasa.gov). As part of our best practices, a tissue viability testing plan has been developed for the repository, which will assess the quality of samples subjected to long-term storage. We expect that the test results will confirm usability of the samples, enable broader science community interest, and verify operational efficiency of the archives. This work will also support NASA open science initiatives and guides development of NASA directives and policy for curation of biological collections.

Biobank↗
NASA NTRS2017

Telemetry Options for LDB Payloads

The Columbia Scientific Balloon Facility has been designing and building high-altitude balloon power systems for over 26 years. With that experience, we have found certain types of PV panels, batteries, and charge controllers that are reliable in stratospheric environments. The ultimate goal is to ensure that power systems will provide power reliably throughout the duration of an LDB flight. The purpose of this presentation is to provide some general guidelines and best practices for power system design.

Power Systems Design for Long Duration Ballooning↗
NASA NTRS2017

Large-Eddy Simulation (LES) of a Compressible Mixing Layer and the Significance of Inflow Turbulence

In the context of Large Eddy Simulations (LES), the effects of inflow turbulence are investigated through the Synthetic Eddy Method (SEM). The growth rate of a turbulent compressible mixing layer corresponding to operating conditions of GeobelDutton Case 2 is investigated herein. The effects of spanwise width on the growth rate of the mixing layer is investigated such that spanwise width independence is reached. The error in neglecting inflow turbulence effects is quantified by comparing two methodologies: (1) Hybrid-RANS-LES methodology and (2) SEM-LES methodology. Best practices learned from Case 2 are developed herein and then applied to a higher convective mach number corresponding to Case 4 experiments of GeobelDutton.

les↗
NASA NTRS2016

Final Report of the NASA Technology Readiness Assessment (TRA) Study Team

The material in this report covers the results on the NASA-wide TRA team, who are responsible for ascertaining the full extent of issues and ambiguities pertaining to TRATRL and to provide recommendations for mitigation. The team worked for approximately 6 months to become knowledgeable on the current TRATRL process and guidance and to derive recommendations for improvement.The team reviewed the TRA processes of other government agencies (OGA), including international agencies, and found that while the high-level processes are similar, the NASA process has a greater level of detail. Finally, NASA’s HQ OCT continues to monitor the GAO’s efforts to produce a TRA Best Practices Guide, a draft of which was received in February 2016. This Guide could impact the recommendations of this report.

Technology readiness assessment↗
NASA NTRS2016

Three-Dimensional Modeling of Aircraft High-Lift Components with Vehicle Sketch Pad

Vehicle Sketch Pad (OpenVSP) is a parametric geometry modeler that has been used extensively for conceptual design studies of aircraft, including studies using higher-order analysis. OpenVSP can model flap and slat surfaces using simple shearing of the airfoil coordinates, which is an appropriate level of complexity for lower-order aerodynamic analysis methods. For three-dimensional analysis, however, there is not a built-in method for defining the high-lift components in OpenVSP in a realistic manner, or for controlling their complex motions in a parametric manner that is intuitive to the designer. This paper seeks instead to utilize OpenVSP's existing capabilities, and establish a set of best practices for modeling high-lift components at a level of complexity suitable for higher-order analysis methods. Techniques are described for modeling the flap and slat components as separate three-dimensional surfaces, and for controlling their motion using simple parameters defined in the local hinge-axis frame of reference. To demonstrate the methodology, an OpenVSP model for the Energy-Efficient Transport (EET) AR12 wind-tunnel model has been created, taking advantage of OpenVSP's Advanced Parameter Linking capability to translate the motions of the high-lift components from the hinge-axis coordinate system to a set of transformations in OpenVSP's frame of reference.

Olson, Erik D.↗
NASA NTRS2017

Summary of Propagation Cases of the Second AIAA Sonic Boom Prediction Workshop

A summary is provided for the propagation portion of the second AIAA Sonic Boom Workshop held January 8, 2017 in conjunction with the AIAA SciTech 2017 conference. Near-field pressure waveforms for two cases were supplied and ground signatures at multiple azimuthal angles as well as their corresponding loudness metrics were requested from 10 participants, representing 3 countries. Each case had some required runs, as well as some optional runs. The required cases included atmospheric profiles with measured data including winds, using Radiosonde balloon data at multiple geographically spread locations, while the optional cases included temperature and pressure profiles from the US Standard atmosphere. The humidity profiles provided for the optional cases were taken from ANSI guidance, as the authors were unaware of an accepted standard at the time the cases were released to the participants. Participants provided ground signatures along with the requested data, including some loudness metrics using their best practices, which included lossy as well as lossless schemes. All the participants' submissions, for each case, are compared and discussed. Noise or loudness measures are calculated and detailed comparisons and statistical analyses are performed and presented. It has been observed that the variation in the loudness measures and spread between participants' submissions increased as the computation proceeded from under-track locations towards the lateral cut-off. Lessons learned during this workshop are discussed and recommendations are made for potential improvements and possible subsequent workshops as we collectively attempt to refine our analysis methods.

Rallabhandi, Sriram↗
NASA NTRS2017

USM3D Simulations for Second Sonic Boom Workshop

The NASA Tetrahedral Unstructured Software System with the USM3D flow solver was used to compute test cases for the Second AIAA Sonic Boom Prediction Workshop. The intent of this report is to document the USM3D results for SBPW2 test cases. The test cases included an axisymmetric equivalent area body, a JAXA wing body, a NASA low boom supersonic configuration modeled with flow through nacelles and engine boundary conditions. All simulations were conducted for a free stream Mach number of 1.6, zero degrees angle of attack, and a Reynolds number of 5.7 million per meter. Simulations were conducted on tetrahedral grids provided by the workshop committee, as well as a family of grids generated by an in-house approach for sonic boom analyses known as BoomGrid using current best practices. The near-field pressure signatures were extracted and propagated to the ground with the atmospheric propagation code, sBOOM. The USM3D near-field pressure signatures, corresponding sBOOM ground signatures, and loudness levels on the ground are compared with mean values from other workshop participants.

Elmiligui, Alaa↗
NASA NTRS2017

Earth Science Project Office (ESPO) Field Experiences During ORACLES, ATom, KORUS and POSIDON

Very often, scientific field campaigns entail years of planning and incur substantial cost, especially if they involve the operation of large research aircraft in remote locations. Deploying and operating these aircrafts even for short periods of time poses challenges that, if not addressed properly, can have significant negative consequences and potentially jeopardize the success of a scientific campaign. Challenges vary from country to country and range from safety, health, and security risks to differences in cultural and social norms. Our presentation will focus on sharing experiences on the ESPO 2016 conducted field campaigns ORACLES, ATom, KORUS and POSIDON. We will focus on the best practices, lessons learned, international relations and coordination aspects of the country-specific experiences. This presentation will be part of the ICARE Conference (2nd International Conference on Airborne Research for the Environment (ICARE 2017) that will focus on "Developing the infrastructure to meet future scientific challenges". This unique conference and gathering of facility support experts will not only allow for dissemination and sharing of knowledge but also promote collaboration and networking among groups that support scientific research using airborne platforms around the globe.

Salazar, Vidal↗