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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 109 records · Page 6
All sourcesNASA NTRSDOE OSTI
NASA NTRS1982

System Requirements and Operations Panel Workshop summary

The low Earth orbit (LEO) versus the geosynchronous Earth orbit (GEO) deployment systems were discussed. The following items are emphasized: (1) large area systems, such as deployment, altitude, orbit transfer, and on orbit operation; (2) propulsion oriented issues such as the orbit transfer vehicle and the auxiliary propulsion systems; (3) programmatic issues. The LEO versus GEO deployment is a significant driver on propulsion requirements for an orbit transfer vehicle. It is suggested that early systems will be deployed at LEO. The Shuttle remote manipulator system (RMS) will not be involved in early demonstration activities. It is concluded that an integrated large space system/propulsion approach is essential and that propulsion development requirements need to be established.

Schwarzberg, F. R.↗
NASA NTRS2011

Innovative Approach Enabled the Retirement of TDRS-1 Compliant with NASA Orbital Debris Requirements

The first Tracking and Data Relay Satellite (TDRS-1) was deactivated on June 27th 2010 following more than 26 years of operation. The end-of-mission (EOM) operations were developed to address the stringent requirements of NPR 8715.6: NASA Procedural Requirements for Limiting Orbital Debris, which consists of three key items: 1) removal from the geosynchronous arc; 2) depletion of the remaining propellant; and 3) passivation of all sources of energy storage or generation [1]. The EOM approach minimized risks while accomplishing these goals. Raising TDRS-1 over 350 km above geosynchronous was accomplished via proven station change operations. Depleting propellant was the most challenging task, requiring over 20 hours of thruster on-time accumulated within schedule, orbit, and spacecraft subsystem constraints. The attitude configuration and operational procedures, including the unique final passivation method, were thoroughly analyzed and simulated prior to the start of operations. The complete EOM campaign lasted 21 days. The TDRS-1 EOM campaign demonstrated that pre-NPR 8715.6 satellite designs can be made to comply and that lessons learned could be applied to other satellite designs. The significant TDRS-1 effort demonstrates a commitment by NASA to responsible orbital debris management in compliance with international standards.

Zaleski, Ronald↗
NASA NTRS2007

Sensor On-orbit Calibration and Characterization Using Spacecraft Maneuvers

Spacecraft flight operations often require activities that involve different kinds of maneuvers for orbital adjustments (pitch, yaw, and roll). Different maneuvers, when properly planned and scheduled, can also be applied to support and/or to perform on-board sensor calibration and characterization. This paper uses MODIS (Moderate Resolution Imaging Spectroradiometer) as an example to illustrate applications of spacecraft maneuvers for Earth-observing sensors on-orbit calibration and characterization. MODIS is one of the key instruments for NASA's Earth Observing System (EOS) currently operated on-board the EOS Terra and Aqua spacecraft launched in December 1999 and May 2002, respectively. Since their launch, both Terra and Aqua spacecraft have made a number of maneuvers, specially the yaw and roll maneuvers, to support the MODIS on-orbit calibration and characterization. For both Terra and Aqua MODIS, near-monthly spacecraft roll maneuvers are executed for lunar observations. These maneuvers are carefully scheduled so that the lunar phase angles are nearly identical for each sensor's lunar observations. The lunar observations are used to track MODIS reflective solar bands (RSB) calibration stability and to inter-compare Terra and Aqua MODIS RSB calibration consistency. To date, two sets of yaw maneuvers (each consists of two series of 8 consecutive yaws) by the Terra spacecraft and one set by the Aqua spacecraft have been performed to validate MODIS solar diffuser (SD) bi-directional reflectance factor (BRF) and to derive SD screen transmission. Terra spacecraft pitch maneuvers, first made on March 26, 2003 and the second on April 14, 2003 (with the Moon in the spacecraft nadir view), have been applied to characterize MODIS thermal emissive bands (TEB) response versus scan angle (RVS). This is particularly important since the pre-launch TEB RSV measurements made by the sensor vendor were not successful. Terra MODIS TEB RVS obtained from pitch maneuvers have been used in the current LIB calibration algorithm. Lunq observations from pitch maneuvers also provided information to cross-calibrate MODIS with other sensors (MISR and ASTER) on the same platform. We will provide a summary of MODIS maneuver activities and their applications for MODIS calibration and characterization. The results and lessons learned discussed in this paper from MODIS maneuver activities will provide useful insights into future spacecraft and sensor operation.

Xiong, X.↗
NASA NTRS1975

Report of the facility definition team spacelab UV-Optical Telescope Facility

Scientific requirements for the Spacelab Ultraviolet-Optical Telescope (SUOT) facility are presented. Specific programs involving high angular resolution imagery over wide fields, far ultraviolet spectroscopy, precisely calibrated spectrophotometry and spectropolarimetry over a wide wavelength range, and planetary studies, including high resolution synoptic imagery, are recommended. Specifications for the mounting configuration, instruments for the mounting configuration, instrument mounting system, optical parameters, and the pointing and stabilization system are presented. Concepts for the focal plane instruments are defined. The functional requirements of the direct imaging camera, far ultraviolet spectrograph, and the precisely calibrated spectrophotometer are detailed, and the planetary camera concept is outlined. Operational concepts described in detail are: the makeup and functions of shuttle payload crew, extravehicular activity requirements, telescope control and data management, payload operations control room, orbital constraints, and orbital interfaces (stabilization, maneuvering requirements and attitude control, contamination, utilities, and payload weight considerations).

Source record↗
NASA NTRS2017

The GOES In-Situ Geomagnetism Experiment Reimagined

The Geostationary Operational Environmental Satellites (GOES) carry several instruments each with its own requirements. Because accommodating all of them is difficult, there is interest in putting some on their own smaller platforms. The simplest instruments are the magnetometers. These are small and have low communication, attitude control and cleanliness requirements. Getting on-station and operating in close proximity with another satellite, however, requires significant propulsion capabilities. This paper describes a CubeSat mission that goes from geo-transfer to geostationary orbit and operates next to a GOES spacecraft. Requirements, a notional design and performance predictions are provided.

geomagnetism↗
NASA NTRS1985

Extended mission life support systems

Extended manned space missions which include interplanetary missions require regenerative life support systems. Manned mission life support considerations are placed in perspective and previous manned space life support system technology, activities and accomplishments in current supporting research and technology (SR&T) programs are reviewed. The life support subsystem/system technologies required for an enhanced duration orbiter (EDO) and a space operations center (SOC), regenerative life support functions and technology required for manned interplanetary flight vehicles, and future development requirements are outlined. The Space Shuttle Orbiters (space transportation system) is space cabin atmosphere is maintained at Earth ambient pressure of 14.7 psia (20% O2 and 80% N2). The early Shuttle flights will be seven-day flights, and the life support system flight hardware will still utilize expendables.

Quattrone, P. D.↗
NASA NTRS1998

A modernized approach to meet diversified earth observing system (EOS) AM-1 mission requirements

From a flight dynamics perspective, the EOS AM-1 mission design and maneuver operations present a number of interesting challenges. The mission design itself is relatively complex for a low Earth mission, requiring a frozen, Sun-synchronous, polar orbit with a repeating ground track. Beyond the need to design an orbit that meets these requirements, the recent focus on low-cost, 'lights out' operations has encouraged a shift to more automated ground support. Flight dynamics activities previously performed in special facilities created solely for that purpose and staffed by personnel with years of design experience are now being shifted to the mission operations centers (MOCs) staffed by flight operations team (FOT) operators. These operators' responsibilities include flight dynamics as a small subset of their work; therefore, FOT personnel often do not have the experience to make critical maneuver design decisions. Thus, streamlining the analysis and planning work required for such a complicated orbit design and preparing FOT personnel to take on the routine operation of such a spacecraft both necessitated increasing the automation level of the flight dynamics functionality. The FreeFlyer(TM) software developed by AI Solutions provides a means to achieve both of these goals. The graphic interface enables users to interactively perform analyses that previously required many parametric studies and much data reduction to achieve the same result In addition, the fuzzy logic engine enables the simultaneous evaluation of multiple conflicting constraints, removing the analyst from the loop and allowing the FOT to perform more of the operations without much background in orbit design. Modernized techniques were implemented for EOS AM-1 flight dynamics support in several areas, including launch window determination, orbit maintenance maneuver control strategies, and maneuver design and calibration automation. The benefits of implementing these techniques include increased fuel available for on-orbit maneuvering, a simplified orbit maintenance process to minimize science data downtime, and an automated routine maneuver planning process. This paper provides an examination of the modernized techniques implemented for EOS AM-1 to achieve these benefits.

Newman, Lauri Kraft↗
NASA NTRS1998

A Modernized Approach to Meet Diversified Earth Observing System (EOS) AM-1 Mission Requirements

From a flight dynamics perspective, the EOS AM-1 mission design and maneuver operations present a number of interesting challenges. The mission design itself is relatively complex for a low Earth mission, requiring a frozen, Sun-synchronous, polar orbit with a repeating ground track. Beyond the need to design an orbit that meets these requirements, the recent focus on low-cost, "lights out" operations has encouraged a shift to more automated ground support. Flight dynamics activities previously performed in special facilities created solely for that purpose and staffed by personnel with years of design experience are now being shifted to the mission operations centers (MOCs) staffed by flight operations team (FOT) operators. These operators' responsibilities include flight dynamics as a small subset of their work; therefore, FOT personnel often do not have the experience to make critical maneuver design decisions. Thus, streamlining the analysis and planning work required for such a complicated orbit design and preparing FOT personnel to take on the routine operation of such a spacecraft both necessitated increasing the automation level of the flight dynamics functionality. The FreeFlyer(trademark) software developed by AI Solutions provides a means to achieve both of these goals. The graphic interface enables users to interactively perform analyses that previously required many parametric studies and much data reduction to achieve the same result. In addition, the fuzzy logic engine .enables the simultaneous evaluation of multiple conflicting constraints, removing the analyst from the loop and allowing the FOT to perform more of the operations without much background in orbit design. Modernized techniques were implemented for EOS AM-1 flight dynamics support in several areas, including launch window determination, orbit maintenance maneuver control strategies, and maneuver design and calibration automation. The benefits of implementing these techniques include increased fuel available for on-orbit maneuvering, a simplified orbit maintenance process to minimize science data downtime, and an automated routine maneuver planning process. This paper provides an examination of the modernized techniques implemented for EOS AM-1 to achieve these benefits.

Newman, Lauri Kraft↗
NASA NTRSDate not supplied

How Environment and Operational Considerations Guide Requirements Development for Clinical Decision Support Beyond Low Earth Orbit

The Aerospace Medical community is acutely aware of the need for automated cognitive systems to support astronauts in responding to and making critical decisions about assessing – and treating - medical conditions and assuring wellness during exploration spaceflight missions. Such systems will be critically important to mission success as we venture farther from terrestrial settings (particularly low-earth orbit platforms) and encounter increasingly Earth-independent medical decision-making scenarios and requirements. This need would likely be met through the development of a Clinical Decision Support System (CDSS) that assimilates information from various sources (e.g., vehicle environmental control system, blood pressure cuff, and heart rate monitor) integrated with medical and wellness data to provide detailed guidance tailored to individual crew member needs. This presentation will address some of the fundamental considerations and their implications that must be fully understood by CDSS requirement developers early in the system lifecycle.

B Burian↗
NASA NTRS1991

On-orbit coldwelding

Spacecraft mechanisms are required to operate in the space environment for extended periods of time. A significant concern to the spacecraft designer is the possibility of metal to metal coldwelding or significant increases in friction. Coldwelding can occur between atomically clean metal surfaces when carefully prepared in a vacuum chamber on earth. The question is whether coldwelding occurs in orbit service conditions. The results of the System Special Investigation Group's (SIG's) investigation into whether coldwelding had occurred on any Long Duration Exposure Facility (LDEF) hardware are presented. The results of a literature search into previous ground based anomalies is also presented. Results show that even though there have been no documented on-orbit coldwelding related failures, precautions should be taken to ensure that coldwelding does not occur in the space environment and that seizure does not occur in the prelaunch or launch environment.

Dursch, Harry↗
NASA NTRS1995

Measurements of the STS orbiter's angular stability during in-orbit operations

We report on measurements of the angular stability, commonly called 'jitter', of the STS Orbiter during normal operations in space. Measurements were carried out by measuring optically the Orbiter's roll and pitch orientation relative to the solar vector as the orbiter was held in a -Z(sub 0) solar inertial orientation (orbiter bay oriented toward the Sun). We also report observations of an interesting perturbation to the orbiter's orientation noted by the crew during the STS-60 mission. These data may be useful in analyzing the in-orbit response of the Orbiter to thruster firings and other applied torques, and may aid in the planning of future experiments that require fine-pointed operations by the orbiter.

Neupert, Werner M.↗
NASA NTRS1990

Laboratory investigations: Low Earth orbit environment chemistry with spacecraft surfaces

Long-term space operations that require exposure of material to the low earth orbit (LEO) environment must take into account the effects of this highly oxidative atmosphere on material properties and the possible contamination of the spacecraft surroundings. Ground-based laboratory experiments at Los Alamos using a newly developed hyperthermal atomic oxygen (AO) source have shown that not only are hydrocarbon based materials effected but that inorganic materials such as MoS2 are also oxidized and that thin protective coatings such as Al2O3 can be breached, producing oxidation of the underlying substrate material. Gas-phase reaction products, such as SO2 from oxidation of MoS2 and CO and CO2 from hydrocarbon materials, have been detected and have consequences in terms of spacecraft contamination. Energy loss through gas-surface collisions causing spacecraft drag has been measured for a few select surfaces and has been found to be highly dependent on the surface reactivity.

Cross, Jon B.↗
NASA NTRSDate not supplied

Seamless Integration of Multibody and Orbital Dynamics to Support Human Spaceflight Simulations

At the NASA Johnson Space Center (JSC), modeling capability requirements are often driven by the need to simulate upcoming mission scenarios for analysis, procedures development, and training. In preparation for free-flyer vehicle capture, maneuvers, and release, it was determined that the multibody dynamics capabilities provided by MBDyn and the orbital dynamics capabilities supplied by JEOD needed to be merged to properly simulate the dynamic behaviors expected on-orbit. After initial attempts to combine the two packages proved cumbersome, it was decided that a more refined solution was required to facilitate the interface between these two packages. The resulting interface software package was named MBJEOD. The primary design goals for this new package were to leave MBDyn and JEOD untouched, to simplify and clarify simulation initialization for users, and to support any topology or on-orbit operational scenario that future missions might require. This paper provides a detailed overview of MBJEOD and the approach taken to seamlessly integrate the multibody dynamics of MBDyn with the orbital dynamics of JEOD. Additional attention is given to the numerical considerations required for MBJEOD and the simplifying assumptions leveraged to provide for real-time simulation needs. Verification and validation are addressed and current MBJEOD applications at the NASA JSC are discussed.

modeling↗
NASA NTRSDate not supplied

Seamless Integration of Multibody and Orbital Dynamics to Support Human Spaceflight Simulations

At the NASA Johnson Space Center (JSC), modeling capability requirements are often driven by the need to simulate upcoming mission scenarios for analysis, procedures development, and training. In preparation for free-flyer vehicle capture, maneuvers, and release, it was determined that the multibody dynamics capabilities provided by MBDyn and the orbital dynamics capabilities supplied by JEOD needed to be merged to properly simulate the dynamic behaviors expected on-orbit. After initial attempts to combine the two packages proved cumbersome, it was decided that a more refined solution was required to facilitate the interface between these two packages. The resulting interface software package was named MBJEOD. The primary design goals for this new package were to leave MBDyn and JEOD untouched, to simplify and clarify simulation initialization for users, and to support any topology or on-orbit operational scenario that future missions might require. This paper provides a detailed overview of MBJEOD and the approach taken to seamlessly integrate the multibody dynamics of MBDyn with the orbital dynamics of JEOD. Additional attention is given to the numerical considerations required for MBJEOD and the simplifying assumptions leveraged to provide for real-time simulation needs. Verification and validation are addressed and current MBJEOD applications at the NASA JSC are discussed.

modeling↗
NASA NTRS1973

Free-flying teleoperator requirements and conceptual design.

A teleoperator, as defined by NASA, is a remotely controlled cybernetic man-machine system designed to augment and extend man's sensory, manipulative, and cognitive capabilities. Teleoperator systems can fulfill an important function in the Space Shuttle program. They can retrieve automated satellites for refurbishment and reuse. Cargo can be transferred over short or large distances and orbital operations can be supported. A requirements analysis is discussed, giving attention to the teleoperator spacecraft, docking and stowage systems, display and controls, propulsion, guidance, navigation, control, the manipulators, the video system, the electrical power, and aspects of communication and data management. Questions of concept definition and evaluation are also examined.

Onega, G. T.↗
NASA NTRS1985

Utilization of Space Station by the Large Deployment Reflector

The Large Deployable Reflector (LDR), a NASA concept of a very large, orbiting, far infrared submillimeter telescope is described. To be launched in the 1990s, LDR has a projected life of 10 years and is to be serviced every 2 to 3 years. A System Concept and Technology Definition Study of LDR for NASA Ames is currently being conducted. Study results indicate that launch of a 20 m LDR, operating in a 700 to 800 km orbit, requires two shuttle loads. The components of LDR are assembled in a lower parking orbit, and the system is checked out and then transferred to the operational orbit. Furthermore, for servicing, LDR may have to be retrieved to the same lower orbit (and later returned to operational altitude) by an orbit transfer vehicle. These requirements bring up the question of a suitable assembly, checkout, and servicing platform. The deployment process is time consuming and may require special equipment not necessarily available from the orbiter itself. The SS is an attractive choice for that platform.

Bandermann, L. W.↗
NASA NTRS1974

Technical support for guidance, navigation and control space shuttle program

A review of the guidance, navigation and control projects in support of the space shuttle program was conducted. The subjects considered include the following: (1) functional and performance requirements, (2) mission requirements, (3) operating systems software definition, (4) orbit navigation using various sensors, (5) fault detection, isolation and recovery, and (6) passive rendezvous sensors requirements definition.

Source record↗