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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 NTRSDate not supplied

The Gateway as a Building Block for Space Exploration and Development

The Gateway, which will be a small, human-tended space station in orbit around the Moon, is an example of the building block approach to space exploration and development. The National Aeronautics and Space Administration (NASA) leads the Gateway Program and serves as the integrator of the spaceflight capabilities and contributions of U.S. commercial partners and international partners. Gateway is a cornerstone of deep space human exploration, one critical element of the strategies and architectures that will enable human exploration of the solar system. This paper will outline: 1) The concept of operations and describe how Gateway is a multipurpose space station, supporting lunar surface missions, cis-lunar research, and as a proving ground for human missions to Mars; 2) Gateway’s international partnerships as an expansion of the partnerships of the “second generation of space programmes,” namely the International Space Station (ISS); and 3) Future commercial, scientific, and technology demonstration opportunities that this infrastructure building block provides. Lastly, the strategies and architectures for future space exploration and development must include thoughtful approaches to the management and business operations of government space programs. This includes planning for limited outyear growth in budgets, partnership and acquisition strategies, pursuing public-private partnerships and the use of firm-fixed price contracts, enabling vendor-to-vendor relationships, the use of multilateral interoperability standards, and incorporating key lessons learned from prior governmental Programs. This paper will discuss the strategies and approaches undertaken when establishing the Gateway Program at the NASA Johnson Space Center in 2019 and the current operational status of this new, lean, and efficient Program.

Gateway↗
NASA NTRSDate not supplied

The Gateway as a Building Block for Space Exploration and Development

The Gateway, which will be a small, human-tended space station in orbit around the Moon, is an example of the building block approach to space exploration and development. The National Aeronautics and Space Administration (NASA) leads the Gateway Program and serves as the integrator of the spaceflight capabilities and contributions of U.S. commercial partners and international partners. Gateway is a cornerstone of deep space human exploration, one critical element of the strategies and architectures that will enable human exploration of the solar system. This paper will outline: 1) The concept of operations and describe how Gateway is a multi-purpose space station, supporting lunar surface missions, cis-lunar research, and as a proving ground for human missions to Mars; 2) Gateway’s international partnerships as an expansion of the partnerships of the “second generation of space programmes,” namely the International Space Station (ISS); and 3) Future commercial, scientific, and technology demonstration opportunities that this infrastructure building block provides. Lastly, the strategies and architectures for future space exploration and development must include thoughtful approaches to the management and business operations of government space programs. This includes planning for limited outyear growth in budgets, partnership and acquisition strategies, pursuing public-private partnerships and the use of firm-fixed price contracts, enabling vendor-to-vendor relationships, the use of multilateral interoperability standards, and incorporating key lessons learned from prior governmental Programs. This paper will discuss the strategies and approaches undertaken when establishing the Gateway Program at the NASA Johnson Space Center in 2019 and the current operational status of this new, lean, and efficient Program.

Gateway↗
NASA NTRS1996

Thermal Optimization of Growth and Quality in Protein Crystals

Experimental evidence suggests that larger and higher quality crystals can be attained in the microgravity of space; however, the effect of growth rate on protein crystal quality is not well documented. This research is the first step towards providing strategies to grow crystals under constant rates of growth. Controlling growth rates at a constant value allows for direct one-to-one comparison of results obtained in microgravity and on earth. The overall goal of the project was to control supersaturation at a constant value during protein crystal growth by varying temperature in a predetermined manner. Applying appropriate theory requires knowledge of specific physicochemical properties of the protein solution including the effect of supersaturation on growth rates and the effect of temperature on protein solubility. Such measurements typically require gram quantities of protein and many months of data acquisition. A second goal of the project applied microcalorimetry for the rapid determination of these physicochemical properties using a minimum amount of protein. These two goals were successfully implemented on hen egg-white lysozyme. Results of these studies are described in the attached reprints.

Wiencek, John M.↗
NASA NTRS2004

Discrete Spring Model for Predicting Delamination Growth in Z-Fiber Reinforced DCB Specimens

Beam theory analysis was applied to predict delamination growth in DCB specimens reinforced in the thickness direction with pultruded pins, known as Z-fibers. The specimen arms were modeled as cantilever beams supported by discrete springs, which were included to represent the pins. A bi-linear, irreversible damage law was used to represent Z-fiber damage, the parameters of which were obtained from previous experiments. Closed-form solutions were developed for specimen compliance and displacements corresponding to Z-fiber row locations. A solution strategy was formulated to predict delamination growth, in which the parent laminate mode I fracture toughness was used as the criterion for delamination growth. The solution procedure was coded into FORTRAN 90, giving a dedicated software tool for performing the delamination prediction. Comparison of analysis results with previous analysis and experiment showed good agreement, yielding an initial verification for the analytical procedure.

Ratcliffe, James G.↗
NASA NTRS2004

Discrete Spring Model for Predicting Delamination Growth in Z-Fiber Reinforced DCB Specimens

Beam theory analysis was applied to predict delamination growth in Double Cantilever Beam (DCB) specimens reinforced in the thickness direction with pultruded pins, known as Z-fibers. The specimen arms were modeled as cantilever beams supported by discrete springs, which were included to represent the pins. A bi-linear, irreversible damage law was used to represent Z-fiber damage, the parameters of which were obtained from previous experiments. Closed-form solutions were developed for specimen compliance and displacements corresponding to Z-fiber row locations. A solution strategy was formulated to predict delamination growth, in which the parent laminate mode I critical strain energy release rate was used as the criterion for delamination growth. The solution procedure was coded into FORTRAN 90, giving a dedicated software tool for performing the delamination prediction. Comparison of analysis results with previous analysis and experiment showed good agreement, yielding an initial verification for the analytical procedure.

Ratcliffe, James G.↗
NASA NTRS2016

Innovation at the Edge of Space- An Engine for Global Opportunities

Microgravity based commercial opportunities are broad, with applications ranging from fiber optics, device-grade semiconductor crystals, space beads, new materials, cells microencapsulation, 3D tissues and cell cultures, genetic and molecular changes of immune suppression, protein and virus crystal growth, perfume and hair care. To date, primarily the knowledge gained from observing and understanding new end states of systems unraveled in microgravity has been translated into unique technologies and business opportunities on Earth. In some instances existing flight qualified hardware is immediately available for commercial RD for small-scale in-space manufacturing. Overall, products manufactured in microgravity have key properties usually surpassing the best terrestrial counterparts. Commercially, these products have an attractive touch of space which aids in marketing.The talk will addresses the potential benefits of microgravity research for a variety of terrestrial markets by (1) surveying the level of awareness and interest of parties from different commercial sectors (2) assessing the potential of microgravity to stimulate innovation in future product development and (3) formulating a synergistic strategy to use microgravity for economic growth and public benefit.Our findings originating primarily from discussions with 100+ non-aerospace private companies among the high-tech Silicon Valley ecosystem, show that the opportunities and benefits of using the ISS are largely not considered by experts, primarily due to a lack of awareness of the breadth of terrestrial applications that have been enabled or enhanced by microgravity RD. Based on this dialogue, the concept of microgravity verticals is developed to translate the benefits of the microgravity environment into blue ocean business opportunities for various key US commercial sectors.

orbital economy↗
NASA NTRS1972

Maneuver strategies for multi-planet missions.

This paper compares a number of maneuver strategies for five multi-planet missions, including the single planet strategy of nulling the aim-plane and flight-time errors at the immediate target. Significant differences were found among the strategies in the amount of corrective propellant required and the residual miss at each target. In general, nulling or minimization of the residual miss at the next target was found to be superior to that at the immediate target, when error growth is not nulled early. The best strategy corrects aim-plane and flight-time errors at the next target.

Dwivedi, N. P.↗
NASA NTRS1988

University program

Information on university programs, program growth, and space research and technology strategy, are given in viewgraph form.

Hartman, Steven C.↗
NASA NTRS2012

BRIC-17 Mapping Spaceflight-Induced Hypoxic Signaling and Response in Plants

Goals of this work are: (1) Define global changes in gene expression patterns in Arabidopsis plants grown in microgravity using whole genome microarrays (2) Compare to mutants resistant to low oxygen challenge using whole genome microarrays Also measuring root and shoot size Outcomes from this research are: (1) Provide fundamental information on plant responses to the stresses inherent in spaceflight (2) Potential for informing on genetic strategies to engineer plants for optimal growth in space

Gilroy, Simon↗
NASA NTRS2003

Spaceflight hardware for conducting plant growth experiments in space: the early years 1960-2000

The best strategy for supporting long-duration space missions is believed to be bioregenerative life support systems (BLSS). An integral part of a BLSS is a chamber supporting the growth of higher plants that would provide food, water, and atmosphere regeneration for the human crew. Such a chamber will have to be a complete plant growth system, capable of providing lighting, water, and nutrients to plants in microgravity. Other capabilities include temperature, humidity, and atmospheric gas composition controls. Many spaceflight experiments to date have utilized incomplete growth systems (typically having a hydration system but lacking lighting) to study tropic and metabolic changes in germinating seedlings and young plants. American, European, and Russian scientists have also developed a number of small complete plant growth systems for use in spaceflight research. Currently we are entering a new era of experimentation and hardware development as a result of long-term spaceflight opportunities available on the International Space Station. This is already impacting development of plant growth hardware. To take full advantage of these new opportunities and construct innovative systems, we must understand the results of past spaceflight experiments and the basic capabilities of the diverse plant growth systems that were used to conduct these experiments. The objective of this paper is to describe the most influential pieces of plant growth hardware that have been used for the purpose of conducting scientific experiments during the first 40 years of research. c2002 COSPAR. Published by Elsevier Science Ltd. All rights reserved.

Non-NASA Center↗
NASA NTRS2002

Plant adaptation to low atmospheric pressures: potential molecular responses

There is an increasing realization that it may be impossible to attain Earth normal atmospheric pressures in orbital, lunar, or Martian greenhouses, simply because the construction materials do not exist to meet the extraordinary constraints imposed by balancing high engineering requirements against high lift costs. This equation essentially dictates that NASA have in place the capability to grow plants at reduced atmospheric pressure. Yet current understanding of plant growth at low pressures is limited to just a few experiments and relatively rudimentary assessments of plant vigor and growth. The tools now exist, however, to make rapid progress toward understanding the fundamental nature of plant responses and adaptations to low pressures, and to develop strategies for mitigating detrimental effects by engineering the growth conditions or by engineering the plants themselves. The genomes of rice and the model plant Arabidopsis thaliana have recently been sequenced in their entirety, and public sector and commercial DNA chips are becoming available such that thousands of genes can be assayed at once. A fundamental understanding of plant responses and adaptation to low pressures can now be approached and translated into procedures and engineering considerations to enhance plant growth at low atmospheric pressures. In anticipation of such studies, we present here the background arguments supporting these contentions, as well as informed speculation about the kinds of molecular physiological responses that might be expected of plants in low-pressure environments.

NASA Discipline Plant Biology↗
NASA NTRS1980

Cascade Solar Cell Workshop report

Issues related to the feasibility, research and development, and demonstration of a 30% AMO cascade solar cell discussed include the material selection, growth and fabrication techniques, and device development strategy for a monolithic (two terminal) cascade cell, a hybrid (four terminal) cascade cell, and a spectral splitting device (three cells). Workshop recommendations include: (1) initiate a long range research program to develop a three junction, monolithic, cascade cell using either AlGaAsSb-GaAsSb or AlGaInAs-GaInAs material system; (2) emphasize OM-CVD epitaxial growth technique, perhaps combined with other technologies in the near term to obtain tunnel junctions; (3) develop a two junction device first; (4) initiate a cascade solar cell modeling program to study and compare performance of two and four terminal cascade devices exposed to electron and proton irradiation; and (5) encourage and be open to new ideas for developing four terminal, hybrid, cascade cells exploiting novel component cell interconnect technologies.

Hutchby, J. A.↗
NASA NTRS1982

Further developments in the controlled growth approach for optimal structural synthesis

It is pointed out that the use of nonlinear programming methods in conjunction with finite element and other discrete analysis techniques have provided a powerful tool in the domain of optimal structural synthesis. The present investigation is concerned with new strategies which comprise an extension to the controlled growth method considered by Hajela and Sobieski-Sobieszczanski (1981). This method proposed an approach wherein the standard nonlinear programming (NLP) methodology of working with a very large number of design variables was replaced by a sequence of smaller optimization cycles, each involving a single 'dominant' variable. The current investigation outlines some new features. Attention is given to a modified cumulative constraint representation which is defined in both the feasible and infeasible domain of the design space. Other new features are related to the evaluation of the 'effectiveness measure' on which the choice of the dominant variable and the linking strategy is based.

Hajela, P.↗
NASA NTRS1972

The Future of the U. S. Domestic Air Freight Industry

A research project on the future of U.S. domestic air freight operations was conducted. The two main subjects of the project were: (1) during the 1965 to 1969 time period, when the airlines introduced jet freighters into domestic service and air freight traffic growth continued at a high rate, what strategies were employed by management and with what results and (2) what are the opportunities and problems confronting the domestic air freight industry during the 1970 and 1980 time period. The results of the analysis are presented in the form of graphs and tables.

Lewis M Schneider↗
NASA NTRS2017

Supportability Challenges, Metrics, and Key Decisions for Future Human Spaceflight

Future crewed missions beyond Low Earth Orbit (LEO) represent a logistical challenge that is unprecedented in human space flight. Astronauts will travel farther and stay in space for longer than any previous mission, far from timely abort or resupply from Earth. Under these conditions, supportability { defined as the set of system characteristics that influence the logistics and support required to enable safe and effective operations of systems { will be a much more significant driver of space system lifecycle properties than it has been in the past. This paper presents an overview of supportability for future human space flight. The particular challenges of future missions are discussed, with the differences between past, present, and future missions highlighted. The relationship between supportability metrics and mission cost, performance, schedule, and risk is also discussed. A set of pro- posed strategies for managing supportability is presented (including reliability growth, uncertainty reduction, level of repair, commonality, redundancy, In-Space Manufacturing (ISM) (including the use of material recycling and In-Situ Resource Utilization (ISRU) for spares and maintenance items), reduced complexity, and spares inventory decisions such as the use of predeployed or cached spares - along with a discussion of the potential impacts of each of those strategies. References are provided to various sources that describe these supportability metrics and strategies, as well as associated modeling and optimization techniques, in greater detail. Overall, supportability is an emergent system characteristic and a holistic challenge for future system development. System designers and mission planners must carefully consider and balance the supportability metrics and decisions described in this paper in order to enable safe and effective beyond-LEO human space flight.

Owens, Andrew C.↗
NASA NTRS2002

Molecular Genetics of Root Thigmoresponsiveness in Arabidopsis thaliana

The molecular mechanisms that allow plant roots to use gravity and touch as growth guides are investigated. We are using a molecular genetic strategy in Arabidopsis thaliana to study these processes. When Arabidopsis thaliana seedlings grow on tilted hard-agar surfaces, their roots develop a wavy pattern of growth which appears to derive from a succession of left-handed and right-handed circumnutation-like processes triggered by gravity and touch stimulation (Okada and Shimura, 1990; Rutherford et al., 1998; Rutherford and Masson, 1996). Interestingly, mutations that affect root waving on tilted hard-agar surfaces can be identified and characterized. Some of these mutations affect root gravitropism, while others appear to be responsible for the production of abnormal waves (no waves, compressed or square waves, coils) without affecting gravitropism. The specific objectives of this project were to functionally characterize two genes (WVD2 and WVD6) which are required for root waving on tilted agar surfaces, but not for root gravitropism. Specific objectives included a physiological and cytological analysis of the mutants, and molecular cloning and characterization of the corresponding genes. As summarized in this paper, we have reached these objectives. We have also identified and partially characterized other mutations that affect root skewing on hard-agar surfaces (sku5-1 and ago1), and have completed our work on the root-wave phenotype associated with mutations in genes of the tryptophan biosynthesis pathway (Lynn et al., 1999; Rutherford et al., 1998; Sedbrook et al., 2000, 2002). We briefly describe our progress on the cloning and characterization of WVD6, WVD2 and SKU5, and provide a list of papers (published, or in preparation) that derived from this grant. We also discuss the biological implications of our findings, with special emphasis on the analysis of WVD2.

Masson, Patrick H.↗
NASA NTRS1993

Computer-controlled float zone crystal growth

A PC-based computer control system to automate a high-temperature float zone growth of titanium carbide is reported. The control strategy of the computer control system relies on the relations derived from a combination of empirical relations and results from detailed mathematical analysis of the physical transports of the entire float zone assembly. A system control computer program was written to establish real-time determination of the size of the molten zone from a thermal image, control parameters from established relationships, and collected processed data to achieve control objectives. We found that the developed computer control allows the growth process to be operated nearer the stability limit. Any slight variations in growth conditions can be corrected in time to avoid any instability growth, which otherwise cannot be adjusted via manual control.

Chan, Y. T.↗