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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 685 records · Page 38
All sourcesNASA NTRSDOE OSTI
NASA NTRS2017

Risk-Significant Adverse Condition Awareness Strengthens Assurance of Fault Management Systems

As spaceflight systems increase in complexity, Fault Management (FM) systems are ranked high in risk-based assessment of software criticality, emphasizing the importance of establishing highly competent domain expertise to provide assurance. Adverse conditions (ACs) and specific vulnerabilities encountered by safety- and mission-critical software systems have been identified through efforts to reduce the risk posture of software-intensive NASA missions. Acknowledgement of potential off-nominal conditions and analysis to determine software system resiliency are important aspects of hazard analysis and FM. A key component of assuring FM is an assessment of how well software addresses susceptibility to failure through consideration of ACs. Focus on significant risk predicted through experienced analysis conducted at the NASA Independent Verification & Validation (IV&V) Program enables the scoping of effective assurance strategies with regard to overall asset protection of complex spaceflight as well as ground systems. Research efforts sponsored by NASAs Office of Safety and Mission Assurance (OSMA) defined terminology, categorized data fields, and designed a baseline repository that centralizes and compiles a comprehensive listing of ACs and correlated data relevant across many NASA missions. This prototype tool helps projects improve analysis by tracking ACs and allowing queries based on project, mission type, domain/component, causal fault, and other key characteristics. Vulnerability in off-nominal situations, architectural design weaknesses, and unexpected or undesirable system behaviors in reaction to faults are curtailed with the awareness of ACs and risk-significant scenarios modeled for analysts through this database. Integration within the Enterprise Architecture at NASA IV&V enables interfacing with other tools and datasets, technical support, and accessibility across the Agency. This paper discusses the development of an improved workflow process utilizing this database for adaptive, risk-informed FM assurance that critical software systems will safely and securely protect against faults and respond to ACs in order to achieve successful missions.

IV&V↗
NASA NTRS2019

Agile Approach to Assuring the Safety-Critical Embedded Software for NASA's Orion Spacecraft

Human-rated missions like those in NASA's Orion Program continue to grow in complexity. The role of software in achieving ambitious mission objectives has expanded dramatically in the last few decades. Assuring the safety and performance of the embedded flight software is quickly growing beyond the reach of traditional methods and resource levels. The methods used to build these software-dominant systems evolve in an on-going attempt to keep pace with the scope of our ambitions. Agile software development is now commonplace. The long timelines and large batches of work associated with traditional methods are being replaced by rapid delivery of small increments _ as system capabilities are realized in waves. Assurance of these critical software capabilities must therefore conquer an ever-expanding frontier of challenges, and do so with an approach matched to the evolving development methods. This paper recounts the journey of the Orion Independent Verification and Validation (IV&V) team as we addressed this dynamic environment. Widening our aperture to encompass a dramatically larger mission scope, while adjusting our cadence to synchronize with the rapid pace of agile software development, a new approach to IV&V is emerging. This approach is characterized by a sharper focus on mission capabilities, matched with a method to dynamically _follow the risk' as the IV&V team delivers more compelling assurance data in waves. Traditional methods prevalent in IV&V tend to scope the work using artifacts of the development process as they evolve from preliminary to final versions, and the pace of delivery was synchronized with the development timelines prevalent in the waterfall lifecycle. That more static approach is out of phase with the demands of the new environment. Scoping work according to the critical capabilities of the system (rather than artifacts of development) and synchronizing with the rapid pace of agile development, we are moving toward more effective parity with the demands of the environment. We explain the concrete steps we took, the principles that motivated our choices, and the results we have achieved to date.

Capability based assurance↗
DOE OSTI2025

Software Quality Assurance Plan: Cardinal

The Cardinal Software Quality Assurance (SQA) Program aims to provide the controls and processes necessary to enable continuous, high-quality software development while meeting user and program sponsor requirements. This SQA Plan (SQAP) delineates the SQA Program framework for Cardinal by describing the Program activities, organization, and documentation, and by clearly defining the interconnection of all Program items. It should be noted that this SQAP is aligned with the current version of the Argonne Quality Assurance Program Plan, which was designed to align with DOE O 414.1D. This SQAP is also aligned with the revision 10 of the SQAP for MOOSE and MOOSE-based applications.

97 MATHEMATICS AND COMPUTING↗
NASA NTRS1981

To Produce Nutrients for Plant Growth

On July 1, 1979 a new research program entitled "Development of a Prototype Experiment for Treating CELSS and PCELSS Wastes to Produce Nutrients for Plant Growth" was undertaken by the Massachusetts Institute of Technology and the Georgia Institute of Technology under grant from the National Aeronautics and Space Administration's Ames Research Center. The program was designed to be completed over a five-year period, with the work divided into two phases. Phase I covers approximately two years and involves the development of necessary facilities, chemical methodologies and models to allow meaningful experiments during Phase II, which will involve interfacing waste oxidation with plant growth. Homogeneous samples of freeze-dried human feces and urine have been prepared to assure comparability of results among various CELSS waste treatment research groups. A model of food processing wastes within a PCELSS was developed, and an initial batch of waste was prepared. An automated gas chromatographic system to analyze oxidizer effluents was designed and is operational. A state-of-the-art quantitative elemental analysis capability, built around inductively coupled plasma emission spectroscopy and atomic absorption spectroscopy using electrothermal atomization, has been demonstrated. A continuous flow wet oxidation system was constructed and is now operational.

Michael Modell↗
NASA NTRS2022

Reliability-Aware Requirements Development for Autonomy Software

Autonomy is the ability of a system to make decisions and take actions in the presence of uncertainty. Validating autonomy, therefore, is a matter of validating that the system makes intelligent decisions even when there might be discrepancies between the observed and the expected state of the world as well as when the possible outcome of each of the possible courses of action is uncertain. During the requirements engineering phase, the functions, including those that are required to be autonomous and their expected behavior are specified. However, in the case of autonomous software system, it is challenging to specify all possible scenarios that the software may encounter. Additionally, since autonomous behaviors cannot always be fully predetermined, it is difficult to reason about their completeness and correctness. While these challenges are also faced with non-autonomous system, they are more prevalent for autonomous system due to their complexity and emergent behavior. Our efforts have been three-fold. On one hand, we have developed a goal-based method for requirements decomposition. We have embedded this approach into a higher-level systems engineering framework and then developed methods for decision and reliability analysis within this framework. And finally, we use simulation analysis to validate the more theoretical methods and provide a feedback mechanism. The decision analysis approach (DA) helps in identifying and mitigating the run-time risks, by bringing to the forefront the uncertainties, decisions, interactions, and other factors that may cause autonomous software to make erroneous decisions. The DA framework is used to quantify, for each decision that the software can make, failure risk due to uncertainties. The information about the key decisions and circumstances that can cause autonomous system to make incorrect decisions are used to generate test scenarios to be run in a simulator to ensure that the system can handle error-prone circumstances. The results or outcomes from decisions, based on the simulated scenarios, can then be leveraged to further gain insight of the assured system. We combine a goal-based approach with simulation analysis to facilitate requirements development for autonomous systems and further provide a method for run-time systems level reliability considerations during the autonomous software development process. The DA and the reliability analysis methods provide a formalism for the consideration of uncertainty in the run time decision-making process for autonomous software. This formalism considers the uncertainty involved in the outcome of different courses of action, in terms of performance and cost, as well as a method to consider the system level reliability implications. System level reliability considerations for autonomous software decision making contribute to the satisfaction of the system level goals over the lifecycle of a given mission. We demonstrate our approach using a hypothetical rover path planning example. The requirements for our rover simulator are based on existing literature about Mars rovers and lessons learned from real world observations at JPL. The specifics of the autonomy design for the Mars rovers, that have not been previously cleared for external release, are not used for our demonstrations.

Lindvall, Mikael↗
NASA NTRS1997

NASA X-34 Technology in Motion

The X-34 technology development program is a joint industry/government project to develop, test, and operate a small, fully-reusable hypersonic flight vehicle. The objective is to demonstrate key technologies and operating concepts applicable to future reusable launch vehicles. Integrated in the vehicle are various systems to assure successful completion of mission objectives, including the Main Propulsion System (MPS). NASA-Marshall Space Flight Center (MSFC) is responsible for developing the X-34's MPS including the design and complete build package for the propulsion system components. The X-34 will be powered by the Fastrac Engine, which is currently in design and development at NASA-MSFC. Fastrac is a single-stage main engine, which burns a mixture of liquid oxygen (LOX) and kerosene(RP-1). The interface between the MPS and Fastrac engine are critical for proper system operation and technologies applicable to future reusable launch vehicles. Deneb's IGRIP software package with the Dynamic analysis option provided a key tool for conducting studies critical to this interface as well as a mechanism to drive the design of the LOX and RP-1 feedlines. Kinematic models were created for the Fastrac Engine and the feedlines for various design concepts. Based on the kinematic simulation within Envision, design and joint limits were verified and system interference controlled. It was also critical to the program to evaluate the effect of dynamic loads visually, providing a verification tool for dynamic analysis and in some cases uncovering areas that had not been considered. Deneb's software put the X-34 technology in motion and has been a key factor in facilitating the strenuous design schedule.

Beech, Geoffrey↗
NASA NTRSDate not supplied

Radiation Data Collection and Risk Assessment

In order to advance the approach for parts assurance in the space community to the current decade and to remain nimble for the future, NASA GSFC, in collaboration with the Aerospace Corporation’s Mission Success Improvement Workshop and broad space community participation, has been reviewing and categorizing 40 years’ worth of on-orbit anomaly data to support broad assessments of radiation-related risk and the development of tools to rigorously assess risk in general project situations. Part of the changing approach in parts assurance involves phasing in the use of COTS parts (or as preferred, alternate grade parts). This talk will convey some of the early findings of the effort, including the fact that expanded use of COTS parts does not increase radiation-related risk, while also pointing out that a very small percentage of parts in a typical parts list are actives and thus require radiation assessment. These are important because they remove radiation as a factor in broad consideration in the use of COTS, without diminishing the importance of addressing the effects of radiation in space.

risk↗
DOE OSTI2022

A Comprehensive Economic Coal Transition in South Asia

Many countries are considering accelerating their coal transition. A coal transition refers to an energy sector’s shift from a reliance on coal toward an energy mix largely based on cleaner fuels and renewable energy sources. Such a transition is not just related to greenhouse gas emissions, but also encompasses a range of benefits, recognizing that global energy costs and options are changing. Since 2015, proposed new coal power capacity has dropped by three-quarters globally, leaving only a few countries that develop coal-fired power plants at scale (Littlecott et al., 2021). Historic steps were taken at the United Nations Climate Change 26th Conference of Parties (COP26) in Glasgow, as countries pledged to stop new coal builds, end international coal financing, phase down and phase out unabated coal use, and transition to clean energy. In South Asia, there have been several indicators suggesting that countries may be open to moving toward a coal transition. For example, the number of coal power plants under development across South Asia has decreased by 87% since 2015 (Littlecott et al., 2021). However, the challenges of assuring a just transition are substantial. Because coal plays a critical role in the energy and economic systems in South Asia, especially India, moving away from coal means realizing a broader country-wide economic and social transition. A comprehensive, integrated transition strategy for each state is thus needed urgently. This report briefly reviews the current trends and policies on coal in South Asian countries, develops a framework for a comprehensive economic coal transition, and assesses the opportunities and challenges of the transition in key countries. Several important findings emerge from the analysis. First, a coal transition can support overall economic growth and stability. Financial advantages to a well-planned coal transition include mitigating the risk of stranded assets and taking advantage of low-cost renewables. As a global coal transition proceeds, funds are being diverted from new unabated coal power plants, and utilization rates are declining. The likelihood that coal assets will become stranded is increasing, and the potential for future losses therefore increases as well. Second, coal imports in South Asia are rising. Of the coal consumed in Bangladesh, India, Nepal, and Sri Lanka, 32% is imported; this number increases to 94% when excluding India (International Energy Agency [IEA], 2021d). This illustrates a serious energy security risk. One example is the recent increase in coal prices in South Asia, to be discussed in Section 2.2.1. A diverse energy portfolio that incorporates local renewable energy can provide resilience in the face of changing commodity prices and availability. Third, the social benefits of a coal transition include positive health impacts and broader economic improvements in job creation, although assuring a just transition may be a challenge. Phasing out or phasing down coal can significantly reduce air pollutant emissions and therefore minimize associated premature mortality and improve life expectancy. Additional societal benefits of a coal transition include the high economy-wide potential for job creation, although it creates challenges in terms of reintegration and resettlement for coal miners and their communities.

01 COAL, LIGNITE, AND PEAT↗
NASA NTRS1992

Engineering the Lidar In-space Technology Experiment

The Lidar In-space Technology Experiment (LITE) is being developed by NASA for flight on the Space Shuttle in early 1994. A discussion of the NASA four-phase design process is followed by a short history of the experiment heritage. The instrument is then described at the subsystem level from an engineering point of view, with special emphasis on the laser and the receiver. Some aspects of designing for the space environment are discussed, as well as the importance of contamination control, and product assurance. Finally, the instrument integration and test process is described and the current status of the instrument development is given.

Couch, Richard H.↗
DOE OSTI2024

NORTH DAKOTA CARBONSAFE PHASE III: SITE CHARACTERIZATION AND PERMITTING OF GEOLOGIC STORAGE OF CARBON DIOXIDE

The Energy & Environmental Research Center (EERC), in partnership with Minnkota Power Cooperative Inc. (Minnkota), SLB, and Computer Modelling Group Ltd. (CMG), supported wide-scale deployment of carbon capture and storage (CCS) as part of the U.S. Department of Energy (DOE) National Energy Technology Laboratory Carbon Storage Assurance Facility Enterprise (CarbonSAFE) Initiative Phase III. This phase included the acquisition, analysis, and development of information to fully characterize two storage complexes to demonstrate viable storage resources for commercial volumes of CO2 (defined by DOE as a minimum of 50 million tonnes [MMt] of CO2 within a 30-year period) (National Energy Technology Laboratory, 2024). Phase III also involved the preparation, submission, and approval of North Dakota underground injection control (UIC) Class VI storage facility permits (SFPs)—required precursors to applications for Class VI injection well permits. The presumed viability of commercial-scale CCS, situated adjacent to Minnkota’s Milton R. Young Station (MRYS), is validated by Minnkota’s continued pursuit of Project Tundra—an initiative to build the world’s largest lignite-based CCS project in central North Dakota (www.projecttundrand.com). Project Tundra comprises two scopes of work, Tundra Capture (installation of postcombustion CO2 capture at MRYS) and Tundra SGS (secure geologic storage). The efforts of North Dakota CarbonSAFE Phase III, Site Characterization and Permitting, supported Tundra SGS. Extensive site-specific characterization activities included a successful multimeasurement geophysical approach and drilling a stratigraphic test well (J-ROC 1, subsequently renamed Liberty-1) adjacent to MRYS. Core collection and analyses, downhole testing and fluid sampling, and geophysical logging were performed on J-ROC 1 and on a nearby stratigraphic test well (known as J-LOC 1), which was drilled, cored, and tested under a complementary project funded by the North Dakota Lignite Research Program. The injection tests performed on J-LOC 1 positively impacted the CarbonSAFE project, resulting in fewer proposed injection wells and significant construction, operations, and monitoring cost savings. The characterization data collected and analyses performed were integrated into geologic models, and successive numerical simulations were run to determine CO2 plume extent and subsurface pressure buildup associated with the planned CO2 injection rate of nearly 4 MMt per year. The latter doubles the CarbonSAFE Initiative goal with an estimated 100 MMt of CO2 stored in 20 years. Application of the U.S. Environmental Protection Agency’s (EPA’s) method for estimating the Class VI Rule area of review (AOR) to the overpressurized Broom Creek Formation inspired an alternative method of calculation, called risk-based AOR delineation. This peer-reviewed method was applied for the first time during the storage facility-permitting process. The two SFP applications submitted in 2021 successfully resulted in North Dakota Industrial Commission (NDIC) orders in 2022 authorizing the creation of the storage facility areas and amalgamation of pore space as well as establishing financial responsibility requirements. After approval of the SFPs, Minnkota filed in 2022 applications for permits to reenter the J-ROC 1 well and to drill two new wells—all with the intended purpose to become Class VI injection wells. To establish eligibility under the Internal Revenue Code for Section 45Q tax incentives, a monitoring, reporting, and verification (MRV) plan was prepared and submitted by Minnkota to EPA in 2022, resulting in the first such plan approved in North Dakota. Also in 2022, under the National Environmental Policy Act (NEPA), Minnkota prepared and submitted an environmental information volume (EIV) describing the proposed CCS project and associated potential environmental impacts. Based on the EIV, DOE determined that the proposed construction project required an environmental assessment, and Minnkota submitted the first draft in 2023 and a revised draft in 2024. Both submissions were followed by a public comment period. Subsequently, DOE issued a finding of no significant impact (FONSI) on September 13, 2024. A successful outreach program, strongly based in the production, presentation, and dissemination of informational material, fostered an environment to aid stakeholders in making informed decisions regarding the planned project. Opportunities for public input were provided at various steps along the way, including at county planning and zoning meetings, before and during the SFP administrative hearing, and during environmental assessment public comment periods. In addition, land/pore space owners and mineral owners had various points of contact, including granting access rights, securing pore space leasing, and mineral owner notifications. Based upon the successful storage facility permitting issued by NDIC, approval of the MRV plan by EPA, and receipt of a FONSI under the NEPA, Minnkota is continuing its pursuit of Project Tundra. In December 2023, the Office of Clean Energy Demonstrations under its Carbon Capture Demonstrations Projects Program announced funding for the capture system (Office of Clean Energy Demonstrations, 2023) and a proposal for CarbonSAFE Phase IV: Construction funding was submitted in March 2024 for the storage project. A go/no-go decision to proceed with construction and operations in the Broom Creek Formation is anticipated in 2024. References National Energy Technology Laboratory, CarbonSafe Initiative, https://netl.doe.gov/carbon-management/carbon-storage/carbonsafe (accessed August 2024). Office of Clean Energy Demonstrations, 2023, OCED selects three projects in CA, ND, and TX to reduce harmful carbon pollution, create new economic opportunities, and advance carbon reducing technologies, December, www.energy.gov/oced/articles/oced-selects-three-projects-ca-nd-and-tx-reduce-harmful-carbon-pollution-create-new (accessed August 2024).

Peck, Wesley↗
NASA NTRS1973

Structural technologies - Systems challenges and NASA thrusts.

Some significant areas of emphasis in the NASA airframes structures program are highlighted. The topics treated include automated analysis and design processes, building confidence in advanced composites, improving the technology base for future supersonic and hypersonic vehicles, validation of concepts for active control systems, development of predictive methods for aircraft loads and aeroelasticity, and generation of methodology to assure structural integrity as a part of the design process. An integrated long-range program for fatigue and fracture is recommended.

Brooks, G. W.↗
NASA NTRS1975

The Deep Space Network

The primary objectives during this portion of the extended mission were to assure survival of the spacecraft for a third Mercury encounter through conservation of attitude control gas and to conduct trajectory correction maneuvers (TCMs) as necessary to target the spacecraft for a solar occultation zone pass. Special support activities included TCMs 6 and 7 conducted on October 30, 1974 and on February 12-13, 1975, respectively. This period also saw the DSN interface organization involved in (1) the allocation of sufficient coverage to assure accurate orbit determination solutions, (2) monitoring of DSN implementation for Viking to assure maintenance of compatible interfaces and capabilities required for Mariner 10, and (3) the development of encounter coverage, sequences, and readiness test plans.

Source record↗
NASA NTRS1987

Space station System Engineering and Integration (SE and I). Volume 2: Study results

A summary of significant study results that are products of the Phase B conceptual design task are contained. Major elements are addressed. Study results applicable to each major element or area of design are summarized and included where appropriate. Areas addressed include: system engineering and integration; customer accommodations; test and program verification; product assurance; conceptual design; operations and planning; technical and management information system (TMIS); and advanced development.

Source record↗
NASA NTRS1988

Analytical determination of critical crack size in solar cells

Although solar cells usually have chips and cracks, no material specifications concerning the allowable crack size on solar cells are available for quality assurance and engineering design usage. Any material specifications that the cell manufacturers use were developed for cosmetic reasons that have no technical basis. Therefore, the Applied Solar Energy Corporation (ASEC) has sponsored a continuing program for the fracture mechanics evaluation of GaAs. Fracture mechanics concepts were utilized to develop an analytical model that can predict the critical crack size of solar cells. This model indicates that the edge cracks of a solar cell are more critical than its surface cracks. In addition, the model suggests that the material specifications on the allowable crack size used for Si solar cells should not be applied to GaAs solar cells. The analytical model was applied to Si and GaAs solar cells, but it would also be applicable to the semiconductor wafers of other materials, such as a GaAs thin film on a Ge substrate, using appropriate input data.

Chen, C. P.↗
NASA NTRS1989

Product specification documentation standard and Data Item Descriptions (DID). Volume of the information system life-cycle and documentation standards, volume 3

This is the third of five volumes on Information System Life-Cycle and Documentation Standards which present a well organized, easily used standard for providing technical information needed for developing information systems, components, and related processes. This volume states the Software Management and Assurance Program documentation standard for a product specification document and for data item descriptions. The framework can be applied to any NASA information system, software, hardware, operational procedures components, and related processes.

Callender, E. David↗
NASA NTRS1993

Control/structure interaction during Space Station Freedom-Orbiter berthing

The berthing maneuver is essential for the construction and assembly of Space Station Freedom (SSF) and has a direct effect on the SSF assembly build up and SSF/Orbiter operations. The effects of flexible body dynamics coupled with the available control system may impose new requirements on the maneuver. The problem is further complicated by the effect of the SSF control system on the Shuttle Remote Manipulator System (SRMS). These effects will play a major role in the development of operational requirements which need to be identified and validated in order to assure total safety and maneuver execution during SSF construction. This paper presents the results of ongoing studies to investigate the Control/Structure Interaction (CSI) during the berthing operations. The problem is formulated in terms of multi-flex body equations of motion for SSF and the SRMS and on-orbit flight control systems for the SRMS and the SSF, which includes the Control Moment Gyro (CMG) and Reaction Control System (RCS) Attitude Control Systems (ACS). The SSF control system designs are based on the Preliminary Design Review (PDR) version of the Honeywell design. The simulation tool used for the analysis is briefly described and the CSI results are presented for given berthing scenarios.

Hua, Tuyen↗