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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 NTRS1987

Orbital transfer vehicle concept definition and system analysis study, 1986. Volume 9: Study extension results

The purpose of this extension to the OTV Concept Definition and Systems Analysis Study was to improve the definition of the OTV Program that will be most beneficial to the nation in the 1995 to 2010 timeframe. The implications of the defined mission and defined launch vehicle are investigated. The key mission requirements identified for the Space Transportation Architecture Study (STAS) were established and reflect a need for early capability and more ambitious capability growth. The key technical objectives and related issues addressed are summarized. The analyses of selected areas including aerobrake design, proximity operations, and the balance of EVA and IVA operations used in the support of the OTV at the space-base were enhanced. Sensitivity studies were conducted to establish how the OTV program should be tailored to meet changing circumstances.

Kofal, Allen E.↗
NASA NTRS1988

Space Science in the Twenty-First Century: Imperatives for the Decades 1995 to 2015

A unified program is outlined for studying the Earth, from its deep interior to its fluid envelopes. A system is proposed for measuring devices involving both space-based and in-situ observations that can accommodate simultaneously a large range of scientific needs. The scientific objectices served by this integrated infrastructure are cased into a framework of four grand themes. In summary these are: to determine the composition, structure, dynamics, and evolution of the Earth's crust and deeper interior; to establish and understand the structure, dynamics, and chemistry of the oceans, atmosphere, and cryosphere, and their interaction with the solid Earth; to characterize the history and dynamics of living organisms and their interaction with the environment; and to monitor and understand the interaction of human activities with the natural environment. A focus on these grand themes will help to understand the origin and fate of the planet, and to place it in the context of the solar system.

Source record↗
NASA NTRS1988

The quantitative modelling of human spatial habitability

A theoretical model for evaluating human spatial habitability (HuSH) in the proposed U.S. Space Station is developed. Optimizing the fitness of the space station environment for human occupancy will help reduce environmental stress due to long-term isolation and confinement in its small habitable volume. The development of tools that operationalize the behavioral bases of spatial volume for visual kinesthetic, and social logic considerations is suggested. This report further calls for systematic scientific investigations of how much real and how much perceived volume people need in order to function normally and with minimal stress in space-based settings. The theoretical model presented in this report can be applied to any size or shape interior, at any scale of consideration, for the Space Station as a whole to an individual enclosure or work station. Using as a point of departure the Isovist model developed by Dr. Michael Benedikt of the U. of Texas, the report suggests that spatial habitability can become as amenable to careful assessment as engineering and life support concerns.

Wise, James A.↗
NASA NTRS1988

Controls and guidance: Space

The Space Controls and Guidance Research and Technology Program is directed toward enabling the next generation of space transportation systems, large future spacecraft, and space systems such as the Space Station to have large communication antennas and high precision segmented reflector astrophysical telescopes. The new generation of transportation vehicles has demanding requirements to provide for an order of magnitude reduction in cost as well as an increase in capability. The future orbital facilities have demanding control requirements for pointing and stabilization, momentum management, build-up and growth accomodation, and disturbance management. To address these advanced requirements, the research and development program is designed to provide the generic technology base to support the implementation of advanced guidance, navigation, and control. The area of computational controls will be stressed in order to develop cost effective, high speed, high fidelity control system simulation and analysis and synthesis tools. The trust of this work will be to develop methods and software to enable analysis and real-time hardware-in-the-loop simulation of complex spacecraft for control design certification. To address future orbital facilities requirements, an advanced technology program is underway in system identification, distributed control, integrated controls/structures design methods, and advanced sensors and actuators. Because the behavior of large, light weight per unit area deployable/assembled spacecraft is greatly influenced by the ground environment, the testing and verification activity is both ground- and space-based.

Dibattista, John D.↗
NASA NTRS1985

SIRTF Telescope Instrument Changeout and Cryogen Replenishment (STICCR) Study

The Space Infrared Telescope Facility (SIRTF) is a long-life cryogenically cooled space-based telescope for infrared astronomy from 2 to 700 micrometers. SIRTF is currently under study by NASA-ARC (Reference AP) and planned for launch in approximately the mid 1990s. SIRTF will operate as a multiuser facility, initially carrying three instruments at the focal plane. It will be cooled to below 2 K by superfluid liquid helium to achieve radiometric sensitivity limited only by the statistical fluctuations in the natural infrared background radiation over most of its spectral range. The lifetime of the mission will be limited by the lifetime of the liquid helium supply, and baseline is currently to be 2 years. The telescope changes required to allow in-space replenishment of the 4,000-L superfluid helium tank was investigated. A preliminary design for the space services equipment was also developed. The impacts of basing the equipment and servicing on the space station were investigated. Space replenishment and changeout of instruments required changes to the telescope design. Preliminary concepts are presented.

Nast, T. C.↗
NASA NTRS1987

Task planning and control synthesis for robotic manipulation in space applications

Space-based robotic systems for diagnosis, repair and assembly of systems will require new techniques of planning and manipulation to accomplish these complex tasks. Results of work in assembly task representation, discrete task planning, and control synthesis which provide a design environment for flexible assembly systems in manufacturing applications, and which extend to planning of manipulatiuon operations in unstructured environments are summarized. Assembly planning is carried out using the AND/OR graph representation which encompasses all possible partial orders of operations and may be used to plan assembly sequences. Discrete task planning uses the configuration map which facilitates search over a space of discrete operations parameters in sequential operations in order to achieve required goals in the space of bounded configuration sets.

Sanderson, A. C.↗
NASA NTRS1987

Flexible manipulator control experiments and analysis

Modeling and control design for flexible manipulators, both from an experimental and analytical viewpoint, are described. From the application perspective, an ongoing effort within the laboratory environment at the Ohio State University, where experimentation on a single link flexible arm is underway is described. Several unique features of this study are described here. First, the manipulator arm is slewed by a direct drive dc motor and has a rigid counterbalance appendage. Current experimentation is from two viewpoints: (1) rigid body slewing and vibration control via actuation with the hub motor, and (2) vibration suppression through the use of structure-mounted proof-mass actuation at the tip. Such an application to manipulator control is of interest particularly in design of space-based telerobotic control systems, but has received little attention to date. From an analytical viewpoint, parameter estimation techniques within the closed-loop for self-tuning adaptive control approaches are discussed. Also introduced is a control approach based on output feedback and frequency weighting to counteract effects of spillover in reduced-order model design. A model of the flexible manipulator based on experimental measurements is evaluated for such estimation and control approaches.

Yurkovich, S.↗
NASA NTRS1987

Planning assembly/disassembly operations for space telerobotics

Space telerobotic systems will perform complex tasks of assembly, disassembly, and repair of space-based equipment. Planning such tasks requires reasoning about the functional, physical, and geometrical properties of the equipment, as well as a representation of the characteristics and capabilities of the manipulators and sensors available for the task. The And/Or graph is a useful approach to representation of feasible assembly/disassembly sequences and provides the basis for search among alternative strategies. The paper describes the use of parts entropy measures as evaluation criteria for search in the And/Or graph space. This approach leads to candidate task plans which minimize the complexity of intermediate geometrical states.

Sanderson, Arthur C.↗
NASA NTRS1988

Systems aspects of a space nuclear reactor power system

Various system aspects of a 300-kW nuclear reactor power system for spacecraft have been investigated. Special attention is given to the cases of a reusable OTV and a space-based radar. It is demonstrated that the stowed length of the power system is important to mission design, and that orbital storage for months to years may be needed for missions involving orbital assembly.

Jaffe, L.↗
NASA NTRS1988

Pultrusion with thermoplastics for the fabrication of structures in space

The use of the pultrusion method to produce structures in space is proposed. This technique is based on transporting materials in coils or bundles and fabricating the structures in space. Two methods for thermoplastic impregnation of advanced composite are described. The properties of three pultruded thermoplastic matrix materials, polyphenylene sulfide, polyetherimide (PEI), and polyetheretherketone (PEEK) are discussed and evaluated. It is observed that the pultrusions containing PEI and PEEK reveal post-fabrication potential of lightweight, high strength advanced composites and this method of fabrication produces strength values comparable to those of conventional techniques. Earth-based and space-based planetary shelter models are developed and compared. It is noted that cargo storage volume is dependent on a combination of profiles, packaging, and manufacturing methods.

Wilson, Maywood L.↗
NASA NTRS1988

Artificial intelligence approaches to astronomical observation scheduling

Automated scheduling will play an increasing role in future ground- and space-based observatory operations. Due to the complexity of the problem, artificial intelligence technology currently offers the greatest potential for the development of scheduling tools with sufficient power and flexibility to handle realistic scheduling situations. Summarized here are the main features of the observatory scheduling problem, how artificial intelligence (AI) techniques can be applied, and recent progress in AI scheduling for Hubble Space Telescope.

Johnston, Mark D.↗
NASA NTRS1985

Results of an observing system simulation experiment based on the proposed Windsat instrument

Two fraternal twin experiments were conducted as part of this study. A data impact experiment using real data (runs 1 and 2) was conducted to assess the impact that rawin wind observations have on both a 5-day assimilation and a single 5-day forecast generated at the end of each assimilation. An observing system simulation experiment (OSSE) using simulated observations (runs 3, 4, and 5) was conducted in order to first calibrate the OSSE results and second to use this calibration to estimate the 'real world' impact from the contribution of global 3-dimensional wind profiles generated from a space-based lidar system known as Windsat. Each of the three runs in the seond experiment were also 5-day assimilation runs with a 5-day forecast initialized from the last 6-hour update cycle of the assimilation. The data impact study revealed a consistent positive impact when rawin winds were added back into an otherwise complete FGGE data set. Both the 6-hour and 5-day forecasts were improved at all levels, in both hemispheres, and for both the wind and the geopotential height fields. Similar results were obtained from the two parallel simulation runs, 3 and 4. Together with the results from runs 1 and 2, calibration coefficients were generated so as to 'correct' the results determined from the addition of Windsat winds (run 5). The Windsat simulation showed a positive improvement in all cases studied. Even though only the tropics were enhanced with these wind observations, hemispheric rms errors were decreased in both the assimilation and 5-day forecast. The 6-hour forecasts of zonal wind from the assimilation run were improved by as much as 50 pct. on the average, and the single forecast showed an average improvement of near 30 pct. Even though these calibrated values are considered too optimistic, the skill of the forecast generated from this run extended the useful forecast period by 18-24 hours.

Arnold, Charles P., Jr.↗
NASA NTRS1986

FASAC Technical Assessment Report: Soviet Space Science Research

This report is the work of a panel of eight US scientists who surveyed and assessed Soviet research in the spare sciences. All of the panelists were very familiar with Soviet research through their knowledge of the published scientific literature and personal contacts with Soviet and other foreign colleagues. In addition, all of the panelists reviewed considerable additional open literature--scientific, and popular, including news releases. The specific disciplines of Soviet space science research examined in detail for the report were: solar-terrestrial research, lunar and planetary research, space astronomy and astrophysics, and, life sciences. The Soviet Union has in the past carried out an ambitious program in lunar exploration and, more recently, in studies of the inner planets, Mars and especially Venus. The Soviets have provided scientific data about the latter planet which has been crucial for studies of the planet's evolution. Future programs envision an encounter with Halley's Comet, in March 1986, and missions to Mars and asteroids. The Soviet programs in the life sciences and solar-terrestrial research have been long-lasting and systematically pursued. Much of the ground-based and space-based research in these two disciplines appears to be motivated by the requirement to establish long-term human habitation in near-Earth space. The Soviet contributions to new discoveries and understanding in observational space astronomy and astrophysics have been few. This is in significant contrast to the very excellent theoretical work contributed by Soviet scientists in this discipline.

Lanzerotti, L. J.↗
NASA NTRS1981

Yacht Race Monitoring

Observer Single-handed Transatlantic Race (OSTAR) participants were aided by a French-American space-based monitoring system which reported the yacht's positions throughout the race, and also served as an emergency locator service. Originating from NASA's Nimbus 6 Satellite, use of this system, called ARGOS made the OSTAR competition the most accurately reported sea race ever conducted. Each boat carried a portable transmitter allowing 88 new sources of oceanographic data available during the race.

Source record↗
DOE OSTI2024

UZrCN Synthesis via Arc Melting - A Novel Synthesis Study

The next generation of nuclear reactors for both power production and space nuclear propulsion require fuel that is more durable, thermally stable, and more thermally conductive to support rapid heat transfer. High temperature gas reactors (HTGR), advanced gas reactors (AGR), and space-based nuclear thermal propulsion (NTP) are advanced reactor concepts that require a fuel type that can withstand high temperatures (1000-2900K) and flow of corrosive gas coolants such as helium, hydrogen, and carbon dioxide. One fuel with the potential to meet these demanding requirements is uranium-zirconium-carbonitride (UZrCN). UZrCN has many favorable fuel qualities compared to other eligible fuel forms such as uranium dioxide (UO2) and uranium mononitride (UN) that could support the aforementioned reactor concepts. UZrCN has an exceptionally high operating temperature and thermal conductivity which are highly desirable to improve reactor economics and safety. It far exceeds the properties of UO2 which is the most common fuel form in the United States. UZrCN also surpasses UN in terms of thermal conductivity and operating temperature by eliminating the dissociation problem UN has at 1700K. UZrCN could improve gas reactor performance and enable NTP technologies; however, it is an under-researched fuel that lacks rigorous scientific study. In recent efforts by the Idaho National Laboratory, a variety of novel methods to produce this fuel composition have been explored. One such method is via arc melting of uranium, zirconium, and carbon under a nitrogen atmosphere. Alloy fabrication using arc melting has been utilized for close to 150 years now and is well-understood as a method for rapid alloy prototyping. This process will be used to perform in-situ nitriding to form UZrCN.

36 MATERIALS SCIENCE↗
DOE OSTI2024

UZrCN Formation via Arc Melting – A Novel Synthesis Study

The next generation of nuclear reactors for both power production and space nuclear propulsion require fuel that is more durable, thermally stable, and more thermally conductive to support rapid heat transfer. High temperature gas reactors (HTGR), advanced gas reactors (AGR), and space-based nuclear thermal propulsion (NTP) are advanced reactor concepts that require a fuel type that can withstand high temperatures (1000-2900K) and flow of corrosive gas coolants such as helium, hydrogen, and carbon dioxide. One fuel with the potential to meet these demanding requirements is uranium-zirconium-carbonitride (UZrCN). UZrCN has many favorable fuel qualities compared to other eligible fuel forms such as uranium dioxide (UO2) and uranium mononitride (UN) that could support the aforementioned reactor concepts. UZrCN has an exceptionally high operating temperature and thermal conductivity which are highly desirable to improve reactor economics and safety. It far exceeds the properties of UO2 which is the most common fuel form in the United States. UZrCN also surpasses UN in terms of thermal conductivity and operating temperature by eliminating the dissociation problem UN has at 1700K. UZrCN could improve gas reactor performance and enable NTP technologies; however, it is an under-researched fuel that lacks rigorous scientific study. In recent efforts by the Idaho National Laboratory, a variety of novel methods to produce this fuel composition have been explored. One such method is via arc melting of uranium, zirconium, and carbon under a nitrogen atmosphere. Alloy fabrication using arc melting has been utilized for close to 150 years now and is well-understood as a method for rapid alloy prototyping. This process will be used to perform in-situ nitriding to form UZrCN.

36 MATERIALS SCIENCE↗
DOE OSTI2026

Reliable Power for Remote Applications

Optical power beaming - using lasers to transmit energy across distances - could change how remote devices receive power. The National Laboratory of the Rockies (NLR) seeks partners to explore the next stage in long-distance power beaming for terrestrial and space-based applications.

14 SOLAR ENERGY↗