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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 73 records · Page 4
All sourcesNASA NTRSDOE OSTI
NASA NTRS2012

An Altair Overview: Designing a Lunar Lander for 21st Century Human Space Exploration

Altair, the lunar lander element of NASA's Constellation program, was conducted in a different design environment than many other NASA projects of similar scope. Because of this relatively unique approach, there are a number of significant success stories that should be considered during the development of any future lunar landers or human spacecraft. This paper is divided into two separate themes; the first is the approach used during the conceptual design studies, including the systematic analysis cycles and the decision making process associated with each: and the second is a summary of the resulting lessons learned that were compiled after looking back at the lifetime of the Project. Altair was terminated before entering Phase B of its design, and was often criticized for being a very heavy and very large vehicle. While there was specific rationale for all of the decisions that led up to that configuration, future design cycles were specifically planned to re-address the mass challenge. Had the project continued, the deliberate, stepwise design process would have converged on an optimized lander design that balanced mass, risk, cost and capabilities. Some of the specific items that will be addressed in this paper include project development strategy, organizational approach and team dynamics, risk-informed design process, mission architecture constraints, mission key driving requirements, model-based systems engineering process, configuration studies, contingency considerations, subsystem overviews and key trade studies. The paper will conclude with a summary of the lessons identified during the Altair project and make suggestions for application to future studies.

Brown, Kendall K.↗
DOE OSTI2021

Framework for an adaptive integrated observation system using a hierarchy of machine learning approaches

Focal Area(s): 1. Data acquisition enabled by machine learning, AI, and advanced methods including experimental/network design/optimization, and hardware-related efforts involving AI. 2. Insight gleaned from complex measurements using AI, big data analytics, and other advanced methods, including explainable AI and physics- or knowledge-guided AI Science Challenge and Rationale: Atmospheric processes are stochastic, occur at scales from the micrometer to many kilometers, and are constantly changing over time. Characterizing these interactions and associated environmental conditions using traditional measurement techniques is difficult and can take years to build statistics on atmospheric phenomena that occurs episodically. Developing new innovative approaches to modify sampling strategies in real-time would enable the routine collection of targeted measurements focused on a specific set of science questions.

54 ENVIRONMENTAL SCIENCES↗
NASA NTRS2003

General Environmental Verification Specification

The NASA Goddard Space Flight Center s General Environmental Verification Specification (GEVS) for STS and ELV Payloads, Subsystems, and Components is currently being revised based on lessons learned from GSFC engineering and flight assurance. The GEVS has been used by Goddard flight projects for the past 17 years as a baseline from which to tailor their environmental test programs. A summary of the requirements and updates are presented along with the rationale behind the changes. The major test areas covered by the GEVS include mechanical, thermal, and EMC, as well as more general requirements for planning, tracking of the verification programs.

Milne, J. Scott, Jr.↗
DOE OSTI2024

Avian Activity Classification Using Recurrent Networks to Fuse Videos with Metadata on Imbalanced Datasets

Activity classification plays a crucial role in various real-life scenarios involving both humans and animals. There is an increasing need for precise activity classification focused on avian-solar interactions, as the usage of solar energy facilities, such as photovoltaic array power stations, has been observed to impact bird species richness, behavior, and activity. However, there has been no work to develop an automated system to monitor and classify these avian-solar interactions. All current methods rely on human observers, which is time and human resources costly and subject to errors related to searcher efficiency. With the recent success of Deep Learning models in activity classification problems, this paper develops a recurrent neural network-based model to automatically classify six avian activities around solar energy facilities. Our proposed model integrates critical feature engineering metadata with video frame data, enabling improved learning and more accurate activity classification. Furthermore, we address the challenge of data imbalance during training and demonstrate the efficacy of our model in detecting and classifying different activities within video tracks. Additionally, we analyze the saliency/backpropagation map of the trained proposed model and validate its decision-making rationale.

Avian activity classification; bidirectional LSTM;↗
NASA NTRS2002

Human Lunar Destiny: Past, Present, and Future

This paper offers conceptual strategy and rationale for returning astronauts to the moon. NASA's historic Apollo program enabled humans to make the first expeditionary voyages to the moon and to gather and return samples back to the earth for further study. To continue exploration of the moon within the next ten to fifteen years, one possible mission concept for returning astronauts using existing launch vehicle infrastructure is presented. During these early lunar missions, expeditionary trips are made to geographical destinations and permanent outposts are established at the lunar south pole. As these missions continue, mining operations begin in an effort to learn how to live off the land. Over time, a burgeoning economy based on mining and scientific activity emerges with the formation of more accommodating settlements and surface infrastructure assets. As lunar activity advances, surface infrastructure assets grow and become more complex, lunar settlements and outposts are established across the globe, travel to and from the moon becomes common place, and commerce between earth and the moon develops and flourishes. Colonization and development of the moon is completed with the construction of underground cities and the establishment of a full range of political, religious, educational, and recreational institutions with a diverse population from all nations of the world. Finally, rationale for diversifying concentrations of humanity throughout earth's neighborhood and the greater solar system is presented.

Fletcher, David↗
NASA NTRS2016

Promoting a Culture of Tailoring for Systems Engineering Policy Expectations

NASA's Marshall Space Flight Center (MSFC) has developed an integrated systems engineering approach to promote a culture of tailoring for program and project policy requirements. MSFC's culture encourages and supports tailoring, with an emphasis on risk-based decision making, for enhanced affordability and efficiency. MSFC's policy structure integrates the various Agency requirements into a single, streamlined implementation approach which serves as a "one-stop-shop" for our programs and projects to follow. The engineers gain an enhanced understanding of policy and technical expectations, as well as lesson's learned from MSFC's history of spaceflight and science missions, to enable them to make appropriate, risk-based tailoring recommendations. The tailoring approach utilizes a standard methodology to classify projects into predefined levels using selected mission and programmatic scaling factors related to risk tolerance. Policy requirements are then selectively applied and tailored, with appropriate rationale, and approved by the governing authorities, to support risk-informed decisions to achieve the desired cost and schedule efficiencies. The policy is further augmented by implementation tools and lifecycle planning aids which help promote and support the cultural shift toward more tailoring. The MSFC Customization Tool is an integrated spreadsheet that ties together everything that projects need to understand, navigate, and tailor the policy. It helps them classify their project, understand the intent of the requirements, determine their tailoring approach, and document the necessary governance approvals. It also helps them plan for and conduct technical reviews throughout the lifecycle. Policy tailoring is thus established as a normal part of project execution, with the tools provided to facilitate and enable the tailoring process. MSFC's approach to changing the culture emphasizes risk-based tailoring of policy to achieve increased flexibility, efficiency, and effectiveness in project execution, while maintaining appropriate rigor to ensure mission success.

Blankenship, Van A.↗
NASA NTRS2004

Identifying, Assessing, and Mitigating Risk of Single-Point Inspections on the Space Shuttle Reusable Solid Rocket Motor

In the production of each Space Shuttle Reusable Solid Rocket Motor (RSRM), over 100,000 inspections are performed. ATK Thiokol Inc. reviewed these inspections to ensure a robust inspection system is maintained. The principal effort within this endeavor was the systematic identification and evaluation of inspections considered to be single-point. Single-point inspections are those accomplished on components, materials, and tooling by only one person, involving no other check. The purpose was to more accurately characterize risk and ultimately address and/or mitigate risk associated with single-point inspections. After the initial review of all inspections and identification/assessment of single-point inspections, review teams applied risk prioritization methodology similar to that used in a Process Failure Modes Effects Analysis to derive a Risk Prioritization Number for each single-point inspection. After the prioritization of risk, all single-point inspection points determined to have significant risk were provided either with risk-mitigating actions or rationale for acceptance. This effort gave confidence to the RSRM program that the correct inspections are being accomplished, that there is appropriate justification for those that remain as single-point inspections, and that risk mitigation was applied to further reduce risk of higher risk single-point inspections. This paper examines the process, results, and lessons learned in identifying, assessing, and mitigating risk associated with single-point inspections accomplished in the production of the Space Shuttle RSRM.

Greenhalgh, Phillip O.↗
NASA NTRS2007

Revitalization of Space-Related Human Factors, Environmental and Habitability Data

The NASA Chief Health and Medical Officer (CHMO) recently directed that the agency establish crew health standards to aid in the development of requirements for future vehicles and habitats. Response to this direction includes development of a new NASA habitability and human factors standard and an accompanying design handbook. The new standard contains high-level, over-arching principles to assure its applicability and usability across all NASA development programs. The handbook will provide detailed design requirements and suggestions that will meet the standards. The information contained in NASA-STD-3000 will be updated and included in the new design handbook. In this approach, each new program will derive detailed program-specific requirements from the new standard using the handbook as a design guide and resource. With the completion of the standard, the focus of this year s effort is the development of the new handbook: Human Integration Design Handbook (HIDH). This is an opportunity for the space flight human factors and habitability community to consolidate up-to-date data for use by NASA programs and designers as well as outside researchers and policy makers looking for the next research focus. The goal of the handbook is to help NASA design and build human space flight systems which accommodate the capabilities and limitations of the crew so as to provide an environment where the crew can live and work effectively, safely, and comfortably. Handbook contents will address that primary goal, addressing unique aspects of space flight and habitation, including reduced gravity conditions, time lags, EVA systems and day/night cycles, not addressed in other standards or handbooks. The handbook will be divided into topics similar to NASA-STD-3000 (anthropometrics, architecture, workstations, etc.) and each topic area will contain elements for designers, human factors practitioners, program managers, operators, and researchers. The handbook will include the following elements: (1) Design considerations include a clear and concise summary of what is important to designers in space vehicle / habitat design, design information to translate Earth-base knowledge to the space environment, space issues and the data necessary to address those issues, and a consistent set of terminology. (2) Updates to Lessons Learned and example solutions from Shuttle and Station program experience will provide historical examples to help prevent repeating mistakes or reinvention of the wheel. (3) Requirements will aid in the translation of standards into program specific requirements. The scope of included requirements will define the pool that each program needs to consider and tailor for their specific program. (4) Requirements rationale will help understanding of the importance of these considerations. The HIDH development team at JSC is finalizing the format of the new handbook, prioritizing topic areas for expansion and update, and contacting subject matter experts within the scientific community to assist with this effort. Plans are also being made to continue handbook expansion and maintenance to assure it remains a valuable resource for human factors and human space flight programs.

Russo, Dane↗
NASA NTRS2023

NASA Engineering and Safety Center Technical Bulletin No. 23-01: Including Key Design Features in Safety-Critical Pyrotechnic Firing Circuits

Pyrotechnic systems often fall into a unique category in that inadvertent activation of these systems resulting from a fault and/or lack of safe margins can lead directly to loss of crew. For example, untimely activation of pyrotechnics used for a flight termination system could override an abort capability. Over the years, NASA and the military have learned lessons about safe pyrotechnic circuit design and test, many of which are codified. However, with NASA’s recent efforts to move toward a development model than leans more heavily on Commercial Partners these requirements have not always been directly levied on projects and in some cases been misinterpreted. This bulletin describes key safety features of pyrotechnic firing circuit design and provides rationale for inclusion of each feature.

Pyrotechnic Firing Curcuits↗
NASA NTRS1999

Beyond the Solar System: A Challenge for Space Propulsion

Scientific exploration beyond the confines of our solar system has recently become a near-term goal for NASA. Early robotic probes beyond the Sun's heliopause [a few hundred Astronomical Units (AU) from the Sun] are planned for the first decade of the 21st century. A leading propulsion system for these early interstellar efforts is the solar sail unfurled as close to the Sun as possible. This report discusses the basic physics of the solar sail, the rationale for interstellar exploration, a recent materials breakthrough influencing solar-sail design concepts, and solar sail kinematics (for the case of sail unfurlment at perihelion from an initially parabolic solar orbit and sail orientation normal to the Sun). A number of possible mission scenarios to distances up to 1,000 AU are presented as is a short discussion of what we must learn to extend our exploratory reach to 10,000 AU.

Matloff, Gregory L.↗
NASA NTRS1996

Project Management Framework to Organizational Transitions

This paper describes a project management framework and associated models for organizational transitions. The framework contains an integrated set of steps an organization can take to lead an organizational transition such as downsizing and change in mission or role. The framework is designed to help an organization do the right work the right way with the right people at the right time. The underlying rationale for the steps in the framework is based on a set of findings which include: defining a transition as containing both near-term and long-term actions, designing actions which respond to drivers and achieve desired results, aligning the organization with the external environment, and aligning the internal components of the organization. The framework was developed based on best practices found in the literature, lessons learned from heads of organizations who have completed large-scale organizational changes, and concerns from employees at the Kennedy Space Center (KSC). The framework is described using KSC.

Kotnour, Tim↗
NASA NTRS1993

Developing scheduling benchmark tests for the Space Network

A set of benchmark tests were developed to analyze and measure Space Network scheduling characteristics and to assess the potential benefits of a proposed flexible scheduling concept. This paper discusses the role of the benchmark tests in evaluating alternative flexible scheduling approaches and defines a set of performance measurements. The paper describes the rationale for the benchmark tests as well as the benchmark components, which include models of the Tracking and Data Relay Satellite (TDRS), mission spacecraft, their orbital data, and flexible requests for communication services. Parameters which vary in the tests address the degree of request flexibility, the request resource load, and the number of events to schedule. Test results are evaluated based on time to process and schedule quality. Preliminary results and lessons learned are addressed.

Moe, Karen L.↗
NASA NTRS2006

Developing Formal Correctness Properties from Natural Language Requirements

This viewgraph presentation reviews the rationale of the program to transform natural language specifications into formal notation.Specifically, automate generation of Linear Temporal Logic (LTL)correctness properties from natural language temporal specifications. There are several reasons for this approach (1) Model-based techniques becoming more widely accepted, (2) Analytical verification techniques (e.g., model checking, theorem proving) significantly more effective at detecting types of specification design errors (e.g., race conditions, deadlock) than manual inspection, (3) Many requirements still written in natural language, which results in a high learning curve for specification languages, associated tools and increased schedule and budget pressure on projects reduce training opportunities for engineers, and (4) Formulation of correctness properties for system models can be a difficult problem. This has relevance to NASA in that it would simplify development of formal correctness properties, lead to more widespread use of model-based specification, design techniques, assist in earlier identification of defects and reduce residual defect content for space mission software systems. The presentation also discusses: potential applications, accomplishments and/or technological transfer potential and the next steps.

requirements engineering↗
DOE OSTI2021

Software-defined Networking for Energy Delivery Systems (SDN4EDS): An Architectural Blueprint (Final Report)

This is the initial version of a reference for suppliers and energy companies of all sizes to deploy networks based on software-defined networking technology (SDN) to improve reliability, reduce cyber security attack surface, and facilitate mitigation of adversarial behavior. It is a living document and will progress over the life cycle of the Software-Defined Networking for Energy Delivery Systems (SDN4EDS) project. Version 2 of this report provides information on the Red Team tabletop assessment performed against the initial reference architecture. Version 3 of this report updates the reference architecture with lessons learned from the Red Team tabletop assessment, as well as provides additional details for the use cases. It also provides information on the decision process that could be used by an organization when considering deploying SDN in their environment. The final version of this report consolidates all the interim reports generated by the project into a final report. It also draws from PNNL’s experience in deploying SDN to make recommendations on how SDN could be deployed in a utility environment, and provides rationale for those decisions allowing individual utilities to make risk-based and knowledge-based decisions on how to best deploy SDN in their own environment

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2021

Software-defined Networking for Energy Delivery Systems (SDN4EDS): An Architectural Blueprint (Final Summary Report)

This is the initial version of a reference for suppliers and energy companies of all sizes to deploy networks based on software-defined networking technology (SDN) to improve reliability, reduce cyber security attack surface, and facilitate mitigation of adversarial behavior. It is a living document and will progress over the life cycle of the Software-Defined Networking for Energy Delivery Systems (SDN4EDS) project. Version 2 of this report provides information on the Red Team tabletop assessment performed against the initial reference architecture. Version 3 of this report updates the reference architecture with lessons learned from the Red Team tabletop assessment, as well as provides additional details for the use cases. It also provides information on the decision process that could be used by an organization when considering deploying SDN in their environment. The final version of this report consolidates all the interim reports generated by the project into a final report. It also draws from PNNL’s experience in deploying SDN to make recommendations on how SDN could be deployed in a utility environment, and provides rationale for those decisions allowing individual utilities to make risk-based and knowledge-based decisions on how to best deploy SDN in their own environment. This summary report provides a higher-level overview of the project reports. Readers interested in additional detail, including results of the Red Team assessments and the final configuration, are encouraged to read the full final report.

97 MATHEMATICS AND COMPUTING↗
NASA NTRS1994

Handbook for handling and storage of nickel-cadmium batteries: Lessons learned

The handbook provides guidelines for the handling and storage of conventional NiCd flight batteries. The guidelines are based on many years of experience with ground and in-flight handling of batteries. The overall goal is to minimize the deterioration and irreversible effects of improper handling of NiCd flight batteries on flight performance. A secondary goal is to provide the reader with an understanding, in nonanalytical terms, of the degradation mechanisms of NiCd cells and how these mechanisms are affected by improper ground handling of flight hardware. Section 2 provides the reader with a brief introduction to NiCd cells. The effects of the environment on NiCd batteries are discussed in Section 3, and Section 4 contains 12 guidelines for battery handling and storage with supporting rationale for each guideline. The appendix provides a synopsis of NiCd cell design and evolution over 30 years of space flight on Goddard Space Flight Center (GSFC) satellites, along with a chronological review of key events that influenced the design of NiCd cells being flown today.

Ford, Floyd E.↗
DOE OSTI2026

Comparative Analysis of Report-Back of Research Results Strategies for Personal Chemical Exposure Data

Background. Report-back of research results (RBRR) is ethically supported and highly requested by participants yet lacks broadly transferable guidelines for RBRR. Effective RBRR must be responsive to target audience needs and may not be addressed by a ‘one-size-fits-all’ approach. Objective. Within a subset of our 19 studies on RBRR, we had the unique opportunity to carry out a comparative analysis of RBRR strategies across cohorts with similar development and evaluation methods, yet distinct in life stage, geography, number and type of chemicals assessed, and community contexts. Methods. We highlight key outcomes from three environmental health studies: an ongoing New York, NY cohort (Fair Start; n=486) and a Detroit, MI cohort (CLEAR; n=34) assessing exposure to ambient urban pollution during pregnancy, and a longitudinal cohort in Houston, TX (Houston-3H) following Hurricane Harvey (n=312). Focus group and survey data were analyzed to identify lessons learned and explore how RBRR supports understanding of environmental health. Results. Commonalities emerged in RBRR development, design, organization, and data visualization, as well as in how RBRR can contribute to an understanding of health-environment connections. Differences included preferences for individual versus community level findings, as well as distinguishable contextual considerations. For pregnancy cohorts, messaging was framed with cultural sensitivity, and to avoid unintended consequences of parental guilt due to prenatal exposures. In the post-disaster Houston-3H study, participants requested additional transparency regarding sampling design and study rationale. Significance. All RBRR case studies reported chemicals without known regulatory or health guidelines, so results were contextualized within the study population. Participants across cohorts requested multi-study comparisons to better understand their results beyond their communities. While foundational RBRR elements (e.g. plain language, graphic organizers) may supersede cohort-specific differences, RBRR should be personalized to encompass perceptions of health across different life-stage, cultural, and environmental contexts.

Vogel, Taylor J.↗
NASA NTRS1993

The rationale for fundamental research in space biology: Introduction and background

With the construction of Space Station Freedom, NASA will have available a new platform for experiments in space that promises many advantages over those already flown. Biologists are poised to take advantage of the greater space, the increased power, and especially the long duration of the station for a cascade of innovative experiments in fundamental science that are long overdue. The unique space environment will provide new dimensions for approaching some of the most challenging problems still facing modern biology. Solutions to basic questions about living systems, which may now be grown through many generations in space, will not only explain abnormalities already observed there, but will add to our understanding of how life functions on Earth. Much will be learned about evolution that has built us the way we are, but also about what it has in store for the Earth's species in the future. NASA must not lose this opportunity to contribute to the welfare of the peoples of the Earth while at the same time create knowledge that will enable human exploration of space in the decades ahead.

Halstead, Thora W.↗