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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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All sourcesNASA NTRSDOE OSTI
NASA NTRS2013

Monitoring Method and Apparatus Using Asynchronous, One-Way Transmission from Sensor to Base Station

A monitoring system is disclosed, which includes a base station and at least one sensor unit that is separate from the base station. The at least one sensor unit resides in a dormant state until it is awakened by the triggering of a vibration-sensitive switch. Once awakened, the sensor may take a measurement, and then transmit to the base station the measurement. Once data is transmitted from the sensor to the base station, the sensor may return to its dormant state. There may be various sensors for each base station and the various sensors may optionally measure different quantities, such as current, voltage, single-axis and/or three-axis magnetic fields.

Jensen, Scott L.↗
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 NTRS1990

Space Station Based Microacceleration Experiment Platform

Normal Space Station Freedom activities, such as docking, astronauts' movement, equipment vibrations, and space station reboosts, exert forces on the structure, resulting in static or transient accelerations greater than many microgravity experiments can tolerate. A solution to this problem is to isolate experiments on a separate platform free from such disturbances. The Space Station Based Microacceleration Experiment Platform, a proposed solution to the Space Station microgravity experiment problem is described. It is modular in design and can be telerobotically assembled and operated. The Microacceleration Experiment Platform (MEP) consists of a minimum configuration platform to which power, propulsion, propellant, and experiment modules are added. The platform's layout is designed to take maximum advantage of the microgravity field structure in orbit.

Barber, Katy↗
NASA NTRS2022

An Analysis of Spatio-Temporal Relationship between Satellite-Based Land Surface Temperature and Station-Based Near-Surface Air Temperature over Brazil

A better understanding of the relationship between land surface temperature (Ts) and near-surface air temperature (Ta) is crucial for improving the simulation accuracy of climate models, developing retrieval schemes for soil and vegetation moisture, and estimating large-scale Ta from satellite-based Ts observations. In this study, we investigated the relationship between multiple satellite-based Ts products, derived from the Atmospheric Infrared Sounder (AIRS) and the Moderate Resolution Imaging Spectroradiometer (MODIS) onboard Aqua satellite, and Ta from 204 meteorological stations over Brazil during 2003–2016. Monthly satellite-based Ts products used in this study include: (1) AIRS Version 6 with 1° spatial resolution, (2) AIRS Version 7 with 1° spatial resolution, (3) MODIS Collection 6 with 0.05° spatial resolution, and (4) MODIS Collection 6 with 1° spatial resolution re-sampled from (3) for a direct comparison with AIRS products. We found that satellite-based Ts is lower than Ta over the forest area, but higher than Ta over the non-forest area. Nevertheless, the correlation coefficients (R) between monthly Ta and four Ts products during 2003–2016 are greater than 0.8 over most stations. The long-term trend analysis shows a general warming trend in temperatures, particularly over the central and eastern parts of Brazil. The satellite products could also observe the increasing Ts over the deforestation region. Furthermore, we examined the temperature anomalies during three drought events in the dry season of 2005, 2010, and 2015. All products show similar spatio-temporal patterns, with positive temperature anomalies expanding in areal coverage and magnitude from the 2005 to 2015 event. The above results show that satellite-based Ts is sensitive in reflecting environmental changes such as deforestation and extreme climatic events, and can be used as an alternative to Ta for climatological studies. Moreover, the observed differences between Ts and Ta may inform how thermal assumptions can be improved in satellite-based retrievals of soil and vegetation moisture or evapotranspiration.

land surface temperature↗
NASA NTRS2015

Programmable Ultra-Lightweight System Adaptable Radio Satellite Base Station

With the explosion of the CubeSat, small sat, and nanosat markets, the need for a robust, highly capable, yet affordable satellite base station, capable of telemetry capture and relay, is significant. The Programmable Ultra-Lightweight System Adaptable Radio (PULSAR) is NASA Marshall Space Flight Center's (MSFC's) software-defined digital radio, developed with previous Technology Investment Programs and Technology Transfer Office resources. The current PULSAR will have achieved a Technology Readiness Level-6 by the end of FY 2014. The extensibility of the PULSAR will allow it to be adapted to perform the tasks of a mobile base station capable of commanding, receiving, and processing satellite, rover, or planetary probe data streams with an appropriate antenna.

Varnavas, Kosta↗
NASA NTRS1984

Mojave Base Station Implementation

A 12.2 meter diameter X-Y mount antenna was reconditioned for use by the crustal dynamic project as a fixed base station. System capabilities and characteristics and key performance parameters for subsystems are presented. The implementation is completed.

Koscielski, C. G.↗
NASA NTRS1984

Space Station based operations and maintenance support to spacecraft, platforms, and orbit transfer vehicle (OTV)

The orbital servicing concepts developed for several existing and planned spacecraft are reviewed to illustrate the evolution and capabilities of Shuttle-based support services, and the potential range of future services are categorized by several criteria including transportation systems requirements, supporting facilities and equipment options, and servicing locations. Implications of Space Station-basing the services are described, along with possible implementing systems. In particular, the technique of 'formation flying' by means of which spacecraft may be physically isolated from each other while maintaining reasonable propellant requirements for maneuvers between them is explored by representative examples. OTV mission support is described as an evolutionary augmentation of the basic Space Station services.

Steincamp, J. W.↗
NASA NTRS1987

Coherent lidar wind measurements from the Space Station base using 1.5 m all-reflective optics

This paper discusses the space-based measurement of atmospheric winds from the point of view of the requirements of the optical system of a coherent CO2 lidar. A brief description of the measurement technique is given and a discussion of previous study results provided. The telescope requirements for a Space Station based lidar are arrived at through discussions of the desired system sensitivity and the need for lag angle compensation.

Bilbro, J. W.↗
NASA NTRS1985

Propagation mechanism of daytime Pc 3-4 pulsations observed at synchronous orbit and multiple ground-based stations

Observational data obtained during the last two decades show that the amplitude of daytime Pc 3-4 magnetic pulsations is controlled by the solar wind conditions. The high degree of correlation between the solar wind parameters and Pc 3-4 pulsations in the dayside magnetosphere suggests that the ultimate cause of the daytime Pc 3-4 pulsations must be the interaction of the solar wind with the earth's magnetosphere. The present paper is concerned with details regarding the control of the properties of the Pc 3-4 pulsations by the solar wind parameters, taking into account observations made at multiple ground-based stations. It is attempted to establish the relation between the daytime Pc 3-4 pulsations at the ground stations and the compressional Pc 3-4 waves in the magnetosphere. Attention is given to the most probable propagation mechanism of the daytime Pc 3-4 pulsations in the magnetosphere.

Yumoto, K.↗
NASA NTRS2013

International Space Station-Based Electromagnetic Launcher for Space Science Payloads

A method was developed of lowering the cost of planetary exploration missions by using an electromagnetic propulsion/launcher, rather than a chemical-fueled rocket for propulsion. An electromagnetic launcher (EML) based at the International Space Station (ISS) would be used to launch small science payloads to the Moon and near Earth asteroids (NEAs) for the science and exploration missions. An ISS-based electromagnetic launcher could also inject science payloads into orbits around the Earth and perhaps to Mars. The EML would replace rocket technology for certain missions. The EML is a high-energy system that uses electricity rather than propellant to accelerate payloads to high velocities. The most common type of EML is the rail gun. Other types are possible, e.g., a coil gun, also known as a Gauss gun or mass driver. The EML could also "drop" science payloads into the Earth's upper

Jones, Ross M.↗
NASA NTRS1988

An operations concept for the Space Station based Astrometric Telescope Facility

The Astrometric Telescope Facility (AFT) will be an orbiting observatory which has been proposed to be attached to the NASA Space Station. The primary scientific objectives of the ATF will be to search for extrasolar planetary systems and to study their characteristics. In addition, the ATF will be able to perform other general astrometric observations of stars within the Milky Way Galaxy. Astrometric Telescope Facility operations from the Space Station will be simple and straightforward compared to other orbiting free-flying telescopes. The astrometric approach to planetary detection, which uses repeated measurements of the same set of target stars over many years, is compatible with simple, repetitive operations of the facility. The support provided by the Space Station and anomaly tolerance features of the ATF design also contribute to the simplicity of the operations concept.

Jackson, Robert W.↗
NASA NTRS2011

Data Reduction and Control Software for Meteor Observing Stations Based on CCD Video Systems

The SPanish Meteor Network (SPMN) is performing a continuous monitoring of meteor activity over Spain and neighbouring countries. The huge amount of data obtained by the 25 video observing stations that this network is currently operating made it necessary to develop new software packages to accomplish some tasks, such as data reduction and remote operation of autonomous systems based on high-sensitivity CCD video devices. The main characteristics of this software are described here.

Madiedo, J. M.↗
NASA NTRS1988

Space Station-based deep-space optical communication experiments

A series of three experiments proposed for advanced optical deep-space communications is described. These proposed experiments would be carried out aboard the Space Station to test and evaluate the capability of optical instruments to conduct data communication and spacecraft navigation for deep-space missions. Techniques for effective data communication, precision spacecraft ranging, and accurate angular measurements will be developed and evaluated in a spaceborne environment.

Chen, Chien-Chung↗
NASA NTRS1986

A Space Station-based search for other planetary systems

The physical forces shaping and maintaining the form of the solar system and disk galaxies are reviewed to define the basis for an observational campaign from the Space Station, to find other planetary systems. The evolution of the distribution of types of matter in the solar system is regarded as typical of the formation of planetary systems around other stars. The observation campaign would cover 100 stars out to 10 pc and last 15-30 yr. Technological challenges which must be met to realize the telescope on the Station are described.

Levy, E. H.↗
NASA NTRS1987

Potential GPS user architecture for the NASA Space Station based on Landsat 4/5 experience

A Landsat 4/5 GPS system is described which uses an inertial reference attitude control system and precision real-time ephemeris generation to achieve precision earth pointing. The system has application to the validation of the use of GPS for the low earth orbit navigation of the Space Station. The present system consists of a receiver/processor assembly (R/PA), an L-band GPS antenna, a precision oscillator, and the Landsat computer. The R/PA is integrated with a GPS receiver which selects, acquires, tracks, times, and decodes navigation signals from GPS satellites in order to derive ephemerides. Ephemeris estimates were found to be accurate to better than 50 meters.

Korenstein, David A.↗
NASA NTRS1986

Engineering graphics data entry for space station data base

The entry of graphical engineering data into the Space Station Data Base was examined. Discussed were: representation of graphics objects; representation of connectivity data; graphics capture hardware; graphics display hardware; site-wide distribution of graphics, and consolidation of tools and hardware. A fundamental assumption was that existing equipment such as IBM based graphics capture software and VAX networked facilities would be exploited. Defensible conclusions reached after study and simulations of use of these systems at the engineering level are: (1) existing IBM based graphics capture software is an adequate and economical means of entry of schematic and block diagram data for present and anticipated electronic systems for Space Station; (2) connectivity data from the aforementioned system may be incorporated into the envisioned Space Station Data Base with modest effort; (3) graphics and connectivity data captured on the IBM based system may be exported to the VAX network in a simple and direct fashion; (4) graphics data may be displayed site-wide on VT-125 terminals and lookalikes; (5) graphics hard-copy may be produced site-wide on various dot-matrix printers; and (6) the system may provide integrated engineering services at both the engineering and engineering management level.

Lacovara, R. C.↗
NASA NTRS1994

A teleoperated system for remote site characterization

The detection and characterization of buried objects and materials is an important step in the restoration of burial sites containing chemical and radioactive waste materials at Department of Energy (DOE) and Department of Defense (DOD) facilities. By performing these tasks with remotely controlled sensors, it is possible to obtain improved data quality and consistency as well as enhanced safety for on-site workers. Therefore, the DOE Office of Technology Development and the US Army Environmental Center have jointly supported the development of the Remote Characterization System (RCS). One of the main components of the RCS is a small remotely driven survey vehicle that can transport various combinations of geophysical and radiological sensors. Currently implemented sensors include ground-penetrating radar, magnetometers, an electromagnetic induction sensor, and a sodium iodide radiation detector. The survey vehicle was constructed predominantly of non-metallic materials to minimize its effect on the operation of its geophysical sensors. The system operator controls the vehicle from a remote, truck-mounted, base station. Video images are transmitted to the base station by a radio link to give the operator necessary visual information. Vehicle control commands, tracking information, and sensor data are transmitted between the survey vehicle and the base station by means of a radio ethernet link. Precise vehicle tracking coordinates are provided by a differential Global Positioning System (GPS).

Sandness, Gerald A.↗
NASA NTRS1992

Definition Of The MSAT-X Network

Report describes state of development of Mobile Satellite Experiment (MSAT-X) network at end of 1989. Network includes mobile stations and base stations communicating by microwave radio relay via geostationary satellite. Provides three types of service: mobile telephone, mobile dispatch and digital data. Summarizes findings which serve as background for discussion of tentative specifications for design of network.

Wang, Charles C.↗