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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 523 records · Page 29
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NASA NTRS1973

Space program payload costs and their possible reduction

The possible ways by which NASA payload costs might be reduced in the future were studied. The major historical reasons for payload costs being as they were, and if there are technologies (hard and soft), or criteria for technology advances, that could significantly reduce total costs of payloads were examined. Payload costs are placed in historical context. Some historical cost breakdowns for unmanned NASA payloads are presented to suggest where future cost reductions could be most significant. Space programs of NOAA, DoD and COMSAT are then examined to ascertain if payload reductions have been brought about by the operational (as opposed to developmental) nature of such programs, economies of scale, the ability to rely on previously developed technology, or by differing management structures and attitudes. The potential impact was investigated of NASA aircraft-type management on spacecraft program costs, and some examples relating previous costs associated with aircraft costs on the one hand and manned and unmanned costs on the other are included.

Vanvleck, E. M.↗
NASA NTRS1975

Planetary exploration - Earth's new horizon /12th von Karman Lecture/

The article gives an account of the history of unmanned exploration of the planets of the solar system, including both earthbound exploration and exploration with spacecraft. Examples of images of the Martian surface are presented along with images obtained in Jupiter and Mercury flybys. Data are presented on the growth of US launch vehicle performance capability, navigation performance, and planetary data rate capability. Basic information regarding the nature of the scientific experiments aboard the Pioneer and Viking spacecraft is given. A case is put forward for the ongoing exploration of the planets as a worthwhile endeavor for man.

Schurmeier, H. M.↗
NASA NTRS1977

Preliminary assessment of the vacuum environment in the wake of large space vehicles

The vacuum environment in the wake region of presently planned large space vehicles is calculated using simplified models of the particle fluxes from the various sources. The fluxes which are calculated come directly from the ambient, are due to ambient particles backscattered from spacecraft emissions, and are due to self scattering of spacecraft emissions. Using nominal values for the surface emissions, the flux density environment behind a large unmanned craft at 550 km altitude is calculated. Calculations indicate that the flux density on a wake vacuum experiment conducted in the vicinity of the shuttle is substantially greater than that behind unmanned craft.

Oran, W. A.↗
NASA NTRS1977

Lunar impact: A history of Project Ranger

Complete history of the Ranger project is provided as a tool for understanding the evolution and operational form of NASA's continuing progress of unmanned space exploration. Basic management techniques, flight operating procedures and technology for NASA's later unmanned lunar and planetary missions were reviewed. Methods for selecting experiments and integrating them with the spacecraft were also investigated.

Hall, R. C.↗
NASA NTRS2018

Orion's Powered Flight Guidance Burn Options for Near Term Exploration Missions

NASA's Orion exploration spacecraft will fly more demanding mission profiles than previous NASA human flight spacecraft. Missions currently under development are destined for cislunar space. The EM-1 mission will fly unmanned to a Distant Retrograde Orbit (DRO) around the Moon. EM-2 will fly astronauts on a mission to the lunar vicinity. To fly these missions, Orion requires powered flight guidance that is more sophisticated than the orbital guidance flown on Apollo and the Space Shuttle. Orion's powered flight guidance software contains five burn guidance options. These five options are integrated into an architecture based on a proven shuttle heritage design, with a simple closed-loop guidance strategy. The architecture provides modularity, simplicity, versatility, and adaptability to future, yet-to-be-defined, exploration mission profiles. This paper provides a summary of the executive guidance architecture and details the five burn options to support both the nominal and abort profiles for the EM-1 and EM-2 missions.

Fill, Thomas↗
NASA NTRS2018

Orion Powered Flight Guidance Burn Options for Near Term Exploration

NASA's Orion exploration spacecraft will fly more demanding mission profiles than previous NASA human flight spacecraft. Missions currently under development are destined for cislunar space. The EM-1 mission will fly unmanned to a Distant Retrograde Orbit (DRO) around the Moon. EM-2 will fly astronauts on a mission to the lunar vicinity. To fly these missions, Orion requires powered flight guidance that is more sophisticated than the orbital guidance flown on Apollo and the Space Shuttle. Orion's powered flight guidance software contains five burn guidance options. These five options are integrated into an architecture based on a proven shuttle heritage design, with a simple closed-loop guidance strategy. The architecture provides modularity, simplicity, versatility, and adaptability to future, yet-to-be-defined, exploration mission profiles. This paper provides a summary of the executive guidance architecture and details the five burn options to support both the nominal and abort profiles for the EM-1 and EM-2 missions.

Fill, Tom↗
NASA NTRS1974

Scientific and technical services directed toward the development of planetary quarantine measures for automated spacecraft

The work is reported, which was performed in the specific tasks of the Planetary Quarantine research program for developing parameter specifications of unmanned scientific missions to the planets. The effort was directed principally toward the advancement of the quarantine technology, applicable to all future missions to planets of biological interest. The emphasis of the research was on coordinated evaluation, analysis, documentation, and presentation of PQ requirements for flight projects such as Viking and Pioneer.

Source record↗
NASA NTRS1975

NASA's international satellite projects and the significance of Helios

An overview is presented concerning the basic NASA ground rules, guidelines, and practices associated with the establishment and conduct of a NASA international cooperative project. The Helios project is the most expensive and scientifically most significant of all of the NASA unmanned cooperative satellites considered. An agreement signed in June 1969 provided for Germany to develop a flight spacecraft with both American and German scientific instruments aboard that would be launched by the U.S. on two separate missions toward the sun. Details of the Helios mission are discussed along with aspects of spacecraft design, subsystem characteristics, and the scientific experiments.

Ousley, G. W.↗
NASA NTRS1992

Developing satellite ground control software through graphical models

This paper discusses a program of investigation into software development as graphical modeling. The goal of this work is a more efficient development and maintenance process for the ground-based software that controls unmanned scientific satellites launched by NASA. The main hypothesis of the program is that modeling of the spacecraft and its subsystems, and reasoning about such models, can--and should--form the key activities of software development; by using such models as inputs, the generation of code to perform various functions (such as simulation and diagnostics of spacecraft components) can be automated. Moreover, we contend that automation can provide significant support for reasoning about the software system at the diagram level.

Bailin, Sidney↗
NASA NTRS2005

Jet Propulsion Laboratory's Space Explorations: History of JPL - Part 1

This slide presentation briefly reviews the history of the Jet Propulsion Laboratory from its founding by Dr von Karman in 1936 for research in rocketry through the post-Sputnik shift to unmanned space exploration in 1957. The presentation also reviews the major JPL missions with views of the spacecraft.

space explorations↗
NASA NTRS2000

Prototype Lithium-Ion Battery Developed for Mars 2001 Lander

In fiscal year 1997, NASA, the Jet Propulsion Laboratory, and the U.S. Air Force established a joint program to competitively develop high-power, rechargeable lithium-ion battery technology for aerospace applications. The goal was to address Department of Defense and NASA requirements not met by commercial battery developments. Under this program, contracts have been awarded to Yardney Technical Products, Eagle- Picher Technologies, LLC, BlueStar Advanced Technology Corporation, and SAFT America, Inc., to develop cylindrical and prismatic cell and battery systems for a variety of NASA and U.S. Air Force applications. The battery systems being developed range from low-capacity (7 to 20 A-hr) and low-voltage (14 to 28 V) systems for planetary landers and rovers to systems for aircraft that require up to 270 V and for Unmanned Aerial Vehicles that require capacities up to 200 A-hr. Low-Earth-orbit and geosynchronousorbit spacecraft pose additional challenges to system operation with long cycle life (>30,000 cycles) and long calendar life (>10 years), respectively.

Manzo, Michelle A.↗
NASA NTRS1991

Solar electric propulsion cargo spacecraft for Mars missions

One of the topics available to the 1990-91 Aerospace Engineering senior class was the development of a preliminary design of an unmanned cargo ferry that would support the Mars mission by bringing equipment and supplies from a low Earth orbit (LEO) to a low Mars orbit (LMO). Several previous studies initiated by NASA have indicated that low-thrust transportation systems seem to offer the best performance for Mars missions. Such systems are characterized by long spiral times during escape and capture maneuvers, high payload mass fractions, and, typically, low propellant mass fractions. Of two main low-thrust candidates, nuclear electric propulsion (NEP) and solar electric propulsion (SEP), only the first one received extensive consideration because it seemed to represent the most promising concept for a manned mission to Mars. However, any sustained Mars initiative will have to include an unmanned cargo transportation system, for which an SEP concept deserves very careful consideration. The key assumptions and requirements established in cooperation with the Space Exploration Initiative office at the NASA Langley Research Center were (1) vehicle is assembled at the Space Station Freedom (SSF); (2) Earth-to-orbit delivery of the vehicle components, propellant, and payload is via shuttle-C; (3) vehicle's cargo mass is 61,000 kg; (4) vehicle delivers cargo to LMO at an altitude of 500 km and inclination of 70 deg; (5) vehicle returns (without cargo) to SSF; (6) vehicle should be reusable for at least three missions; and (7) vehicle is powered by ion argon thrusters. Two configurations were developed by two student teams, working mostly independently.

Source record↗
NASA NTRS1991

Automated target recognition and tracking using an optical pattern recognition neural network

The on-going development of an automatic target recognition and tracking system at the Jet Propulsion Laboratory is presented. This system is an optical pattern recognition neural network (OPRNN) that is an integration of an innovative optical parallel processor and a feature extraction based neural net training algorithm. The parallel optical processor provides high speed and vast parallelism as well as full shift invariance. The neural network algorithm enables simultaneous discrimination of multiple noisy targets in spite of their scales, rotations, perspectives, and various deformations. This fully developed OPRNN system can be effectively utilized for the automated spacecraft recognition and tracking that will lead to success in the Automated Rendezvous and Capture (AR&C) of the unmanned Cargo Transfer Vehicle (CTV). One of the most powerful optical parallel processors for automatic target recognition is the multichannel correlator. With the inherent advantages of parallel processing capability and shift invariance, multiple objects can be simultaneously recognized and tracked using this multichannel correlator. This target tracking capability can be greatly enhanced by utilizing a powerful feature extraction based neural network training algorithm such as the neocognitron. The OPRNN, currently under investigation at JPL, is constructed with an optical multichannel correlator where holographic filters have been prepared using the neocognitron training algorithm. The computation speed of the neocognitron-type OPRNN is up to 10(exp 14) analog connections/sec that enabling the OPRNN to outperform its state-of-the-art electronics counterpart by at least two orders of magnitude.

Chao, Tien-Hsin↗
NASA NTRS2015

An Overview of 2014 SBIR Phase 1 and Phase 2 Communications Technology and Development

NASA's Small Business Innovation Research (SBIR) program focuses on technological innovation by investing in development of innovative concepts and technologies to help NASA mission directorates address critical research needs for Agency programs. This report highlights eight of the innovative SBIR 2014 Phase I and Phase II projects that emphasize one of NASA Glenn Research Center's six core competencies-Communication Technology and Development. The technologies cover a wide spectrum of applications such as X-ray navigation, microsensor instrument for unmanned aerial vehicle airborne atmospheric measurements, 16-element graphene-based phased array antenna system, interferometric star tracker, ultralow power fast-response sensor, and integrated spacecraft navigation and communication. Each featured technology describes an innovation, technical objective, and highlights NASA commercial and industrial applications. This report provides an opportunity for NASA engineers, researchers, and program managers to learn how NASA SBIR technologies could help their programs and projects, and lead to collaborations and partnerships between the small SBIR companies and NASA that would benefit both.

ultralow power fast-response sensor↗
NASA NTRS1994

Fullerenes in an impact crater on the LDEF spacecraft

The fullerenes C60 and C70 have been found to occur naturally on Earth and have also been invoked to explain features in the absorption spectra of interstellar clouds. But no definitive spectroscopic evidence exists for fullerenes in space and attempts to find fullerenes in carbonaceous chondrites have been unsuccessful. Here we report the observation of fullerenes associated with carbonaceous impact residue in a crater on the Long Duration Exposure Facility (LDEF) spacecraft. Laser ionization mass spectrometry and Raman spectroscopy indicate the presence of fullerenes in the crater and in adjacent ejecta. Man-made fullerenes survive experimental hypervelocity (approximately 6.1 km s-1) impacts into aluminium targets, suggesting that space fullerenes contained in a carbonaceous micrometeorite could have survived the LDEF impact at velocities towards the lower end of the natural particle encounter range (<13 km s-1). We also demonstrate that the fullerenes were unlikely to have formed as instrumental artefacts, nor are they present as contaminants. Although we cannot specify the origin of the fullerenes with certainty, the most plausible source is the chondritic impactor. If, alternatively, the impact produced the fullerenes in situ on LDEF, then this suggests a viable mechanism for fullerene production in space.

long duration↗
NASA NTRS1973

Flight experience with Apollo spacecraft propulsion systems

Apollo 17 ended the most successful application of rocket propulsion systems in man's history. A total of 23 developmental and manned operational flights were made. Seven hundred and sixty-three spacecraft rocket engines were flown in the program. Over 6 h of manned rocket flights were logged by the spacecraft propulsion systems and approximately one million rocket engine firings were made. One engine failure was encountered on an early unmanned flight as a result of a failure in the guidance programmer which caused the engine to operate in a manner known to cause failures. Numerous operational problems and malfunctions were observed; however, system and component redundancy prevented loss of mission objectives and never jeopardized crew safety. Performance of all systems was usually nominal and most problems were merely nuisances. This paper will present some highlights of Apollo propulsion performance and will provide a bibliography of all flight results.

Thibodaux, J. G., Jr.↗