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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 235 records · Page 13
All sourcesNASA NTRSDOE OSTI
NASA NTRS1987

Potential propellant storage and feed systems for space station resistojet propulsion options

The resistojet system has been defined as part of the baseline propulsion system for the initial Operating Capability Space Station. The resistojet propulsion module will perform a reboost function using a wide variety of fluids as propellants. There are many optional propellants and propellant combinations for use in the resistojet including (but not limited to): hydrazine, hydrogen, oxygen, nitrogen, water, carbon dioxide, and methane. Many different types of propulsion systems have flown or have been conceptualized that may have application for use with resistojets. This paper describes and compares representative examples of these systems that may provide a basis for space station resistojet system design.

Bader, Clayton H.↗
NASA NTRS1986

Earth vicinity trades and options

The options for recovering a returned manned Mars spacecraft are surveyed. Earth parking orbits from libration point to low circular are discussed, with a 500 km perigee, 24 hour period elliptical orbit chosen as a baseline for further calculation. Several techniques for recovering up to 100 metric tons of returned spacecraft are investigated, including recovery by a low Earth orbit (LEO) based orbit transfer vehicle (OTV) pushing the spacecraft to LEO, and OTV transporting and aerobrake to the spacecraft, and an OTV delivering propellant to the spacecraft. Methods utilizing OTVs results in less total mass in LEO, but may not be the minimum cost solutions if significant development and testing are required.

William R Stump↗
NASA NTRS1987

Space Station based options for orbiter docking/berthing

Conceptual efforts to develop a Space Station based system for docking and/or berthing the NSTS Orbiter are described. Past docking and berthing systems are reviewed, the general requirements and options for mating the Orbiter and Space Station are discussed, and the rationale for locating the system on the Station is established. One class of Station-based system is developed in several variations and evaluated with respect to weight distribution, loads, safety, reliability, viewing, and maintainability. An evolutionary presentation of the variations provides insight into the development process and the problems encountered. An overall evaluation of the Station-based variations compared to an optimized Orbiter-based system demonstrates the potential benefits of this approach as well as the issues that must be resolved to realize the benefits.

Hoover, Daniel J.↗
NASA NTRS1987

Trajectory options for the Comet Rendezvous Asteroid Flyby mission

The Comet Rendezvous Asteroid Flyby mission is strongly supported by the scientific community. Two major events during the past year have forced a re-analysis of the mission options, with the goal of selecting a baseline mission for launch in 1993. Venus and earth gravity assists can be used to allow rendezvous with comet Tempel 2 in 1996; the scientific potential of the resulting mission is excellent. Although backup mission opportunities have been identified, the significantly longer flight times weaken the scientific appeal of these missions.

Miller, S. L.↗
NASA NTRS1987

Geosynchronous earth orbit base propulsion - Electric propulsion options

Electric propulsion and chemical propulsion requirements for a geosynchronous earth orbit (GEO) base were analyzed. The base is resupplied from the Space Station's low earth orbit. Orbit-transfer Delta-Vs, nodal-regression Delta-Vs and orbit-maintenance Delta-Vs were considered. For resupplying the base, a cryogenic oxygen/hydrogen (O2/H2) orbital transfer vehicle (OTV) is currently-baselined. Comparisons of several electric propulsion options with the O2/H2 OTV were conducted. Propulsion requirements for missions related to the GEO base were also analyzed. Payload data for the GEO missions were drawn from current mission data bases. Detailed electric propulsion module designs are presented. Mission analyses and propulsion analyses for the GEO-delivered payloads are included.

Palaszewski, B.↗
NASA NTRS1987

Evaluation of cryogenic system test options for the OTV on-orbit propellant depot

Future space missions to geosynchronous, lunar, and planetary orbits will require an orbital depot for stockpiling propellants. This depot will provide long-term storage of cryogens, requiring new technologies for fluid management in microgravity and further development of thermal management technologies for minimization of cryogen boiloff. Preliminary evaluations have been made to define a test program approach for reducing technical risk through verifying performance models and building a base of engineering data for depot design. A number of testing options were defined and evaluated, leading to selection of ground testing combined with an orbital systems test. Ground testing is inadequate because of critical microgravity concerns; extending testing aboard the Space Station was eliminated because the data would not be available soon enough to benefit the propellant depot design. The orbital test would either be a short-term test carried out in the cargo bay of the Space Shuttle Orbiter using a nonhazardous cryogen or a longer term test carried out with hydrogen aboard a free-flying experiment orbited with an expendable launch vehicle.

Schuster, John R.↗
NASA NTRS1988

Analyzing Solar-Power Options For Spacecraft

Solar Space Power Analysis Code, SOSPAC, developed to examine solar-thermal and photovoltaic power-generation options available for satellite or spacecraft in low orbit around Earth. Is software tool for preliminary analysis of systems and enables engineer to compare areas, weights, and costs of several candidate electric- and thermal-power systems. Configurations studied include photovoltaic arrays and paraboloidal-dish systems to produce electricity only and in various combinations to provide both thermal and electric power. Written in FORTRAN IV.

Selcuk, M. K.↗
NASA NTRS1987

Requirements and options for communications services in support of the Systems Autonomy Demonstration Project

A study of the requirements and options for interconnecting the development systems and demonstration test beds at NASA centers supporting the Systems Autonomy Demonstration Project (SADP) is presented. The communications requirements of SADP development and demonstration environments are described, potential communications protocols are examined, and expected communications error rates and system availability are described.

Brown, Richard M.↗
NASA NTRS1988

Maintenance and supply options

The object of the Maintenance and Supply Option was to develop a high level operational philosophy related to maintenance and supply operations and incorporate these concepts into the Lunar Base Study. Specific products to be generated during this task were three trade studies and a conceptual design of the Logistic Supply Module. The crew size study was performed to evaluate crew sizes from the baseline size of four to a crew size of eight and determine the preferred crew size. The second trade study was to determine the impact of extending surface stay times and recommend a preferred duration of stay time as a function of crew, consumables, and equipment support capabilities. The third trade study was an evaluation of packaging and storage methods to determine the preferred logistics approach to support the lunar base. A modified scenario was developed and served as the basis of the individual trade studies. Assumptions and guidelines were also developed from experience with Apollo programs, Space Shuttle operations, and Space Station studies. With this information, the trade studies were performed and a conceptual design for the Logistic Supply Module was developed.

Source record↗
NASA NTRS1987

Traditional versus rule-based programming techniques - Application to the control of optional flight information

A traditional programming technique for controlling the display of optional flight information in a civil transport cockpit is compared to a rule-based technique for the same function. This application required complex decision logic and a frequently modified rule base. The techniques are evaluated for execution efficiency and implementation ease; the criterion used to calculate the execution efficiency is the total number of steps required to isolate hypotheses that were true and the criteria used to evaluate the implementability are ease of modification and verification and explanation capability. It is observed that the traditional program is more efficient than the rule-based program; however, the rule-based programming technique is more applicable for improving programmer productivity.

Ricks, Wendell R.↗
NASA NTRS1988

The Mariner Mark II high precision scan actuator - Results of an options trade study covering pointing performance and system-wide impacts

Four actuators considered as candidates to meet the requirements of the Mariner Mark II high-precision scan platform are evaluated with respect to such criteria as the net effect on spacecraft mass, required power, cost, expected pointing performance, operational considerations, and necessary control complexity. A direct drive actuator is found to be the most suitable candidate. It is noted that for missions where reactionless actuation results in a lower spacecraft mass due to propellant savings, the option of using a platform mounted or spacecraft mounted reaction wheel for platform momentum compensation and spacecraft attitude control is attractive.

Schier, J. Alan↗
NASA NTRS1988

Risk analysis of earth return options for the Mars rover/sample return mission

Four options for return of a Mars surface sample to Earth were studied to estimate the risk of mission failure and the risk of a sample container breach that might result in the release of Martian life forms, should such exist, in the Earth's biosphere. The probabilities calculated refer only to the time period from the last midcourse correction burn to possession of the sample on Earth. Two extreme views characterize this subject. In one view, there is no life on Mars, therefore there is no significant risk and no serious effort is required to deal with back contamination. In the other view, public safety overrides any desire to return Martian samples, and any risk of damaging contamination greater than zero is unacceptable. Zero risk requires great expense to achieve and may prevent the mission as currently envisioned from taking place. The major conclusion is that risk of sample container breach can be reduced to a very low number within the framework of the mission as now envisioned, but significant expense and effort, above that currently planned is needed. There are benefits to the public that warrant some risk. Martian life, if it exists, will be a major discovery. If it does not, there is no risk.

Source record↗
NASA NTRS1989

Design options and analysis of variable gravity systems in space

Design options for tethered systems which can produce a variable gravity living environment in space are discussed. Parameters of rotating systems are reviewed, and early studies of rotating systems are recalled. Artificial gravity configurations are shown and their individual advantages and disadvantages are examined.

Penzo, Paul A.↗
NASA NTRS1988

Space transportation - Options and opportunities

The development space transportation options to earth orbit and beyond are summarized. The performance of available launch systems is reviewed, including the Scout, Delta, Long March 3, Atlas Centaur, Ariane 3, Titan 34D, Proton, the Japanese M-3S-II, N-1, and H-1, and the Space Shuttle. Launch vehicle which are planned or are under development are examined, including the Conestoga, Industrial Launch Vehicle, Titan II, Delta II, H-II, Ariane 5, Titan IV, and the NASA/DOD Heavy Lift Launch Vehicle. Also, issues pertinent to the development of space transportation vehicles are considered, such as reliability, reduced unit cost, reduced lead time, and improved payload accommodations.

Loftus, J. P., Jr.↗
NASA NTRS1988

Nodes packaging option for Space Station application

Space Station nodes packaging analyses are presented relative to moving environmental control and life support system (ECLSS) equipment from the habitability (HAB) module to node 4, in order to provide more living space and privacy for the crew, remove inherently noisy equipment from the crew quarter, retain crew waste collection and processing equipment in one location, and keep objectionable odor away from the living quarters. In addition, options for moving external electronic equipment from the Space Station truss to pressurized node 3 were evaluated in order to reduce the crew extravehicular-activity time required to install and maintain the equipment. Node size considered in this analysis is 3.66 m in diameter and 5.38 m long. The analysis shows that significant external electronic equipment could be relocated from the Space Station truss structure to node 3, and nonlife critical ECLSS HAB module equipment could be moved to node 4.

So, Kenneth T.↗
NASA NTRS1989

Power from space for use on earth: An emerging global option

The concept of the Earth as a closed ecological system is addressed from the point of view of the availability and use of energy from space and its potential influence on the economies of both developed and developing countries. The results of past studies of the solar power satellite (SPS) are reviewed, and the current international activities exploring various aspects of an SPS are mentioned. The functions of an SPS, including collection of solar energy in orbit, conversion to an intermediate form of energy, transmission of energy from orbit to Earth, and conversion to useful energy in the most appropriate form are discussed. Directions for future developments are addressed including a suggested planning framework. Salient aspects of SPS technologies are presented, and the potential benefits of the uses of lunar materials for the SPS construction are outlined. Scenarios within the context of international participation in a global SPS system are presented. The conclusion is drawn that an SPS system is one of the few promising, globally applicable power generation options that has the potential to meet energy demands in the 21st Century and to achieve the inevitable transition to inexhaustible and renewable energy sources.

Glaser, Peter E.↗
NASA NTRS1989

Power for the moon: Is microwave power beaming an option?

Microwave power beaming options for powering lunar bases are presented in viewgraph form. Information is given on power dependent system masses, a solar source beam power system, a nuclear source beam power system, a three satellite beam power system, antenna configurations, and antenna design.

Cull, Ronald C.↗
NASA NTRS1989

Mission Options for an Electric Propulsion Demonstration Flight Test

Several mission options are discussed for an electric propulsion space test which provides operational and performance data for ion and arcjet propulsion systems and testing of APSA arrays and a super power system. The results of these top-level studies are considered preliminary. Ion propulsion system design and architecture for the purposes of performing orbit raising missions for payloads in the range of 2400 to 2700 kg are described. Focus was placed on a design which can be characterized by simplicity, reliability, and performance. Systems of this design are suitable for an electric propulsion precursor flight which would provide proof of principle data necessary for more ambitious and complex missions.

Garner, Charles↗