Explicity equations for OAO, ATS, and Mariner.
Explicit guidance equations for Atlas/Centaur launch vehicle provides steering and engine cutoff commands for OAO, ATS and Mariner interplanetary missions
Flowers, D. H.↗
SEARCH · Engineering Papers
Results for “Interplanetary Mission”
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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Solar electric interplanetary trajectory and performance data for sub-optimal powered spacecraft
Trajectory and spacecraft design data for unmanned interplanetary missions using suboptimal powered solar electric propulsion
Horsewood, J. L.↗
A forecast of electrically-propelled spacecraft applications.
Solar and nuclear electric propelled spacecraft applications to planetary and interplanetary missions, considering asteroid survey, out-of- ecliptic, Mercury orbiter, comet rendezvous, etc
Kraemer, R. S.↗
Developing the structure to carry man to the planets
Spacecraft design for manned interplanetary missions, considering structural materials and weights, cryogenic insulation, meteoroid protection, landing gear, etc
Anderson, R. A.↗
Planetary ephemerides
Planetary ephemerides accuracy and navigation during interplanetary missions, discussing machine readable ephemerides for outer planets
Melbourne, W. G.↗
Guidance and control analysis and integration
Guidance and control analysis and integration for interplanetary missions
Source record↗
Interplanetary flight projects
Reporting DSN support of active and planned interplanetary missions by Pioneer spacecraft
Source record↗
Deep space monitor communication satellite system Patent
Elimination of tracking occultation problems occurring during continuous monitoring of interplanetary missions by using Earth orbiting communications satellite
Clemens, G. W., Jr.↗
Comparison of the radiation flux profiles and spectral detail from three detailed nongray radiation models at conditions representative of hypervelocity earth entry
The radiation models were compared on the basis of the approaches used for the transport calculations and absorption coefficients and of results obtained for the radiation flux profiles and spectral distributions. The calculated results were for shock layer conditions representative of manned earth reentry from an interplanetary mission. The three models are RATRAP, RADICAL, and MDAC. The results show that significant differences exist in the radiation flux computed by the three models. The RADICAL model was found to depend on fewer approximations, to include more detail, and to require less computer time than the other models.
Suttles, J. T.↗
Material Compatibility with Space Storable Propellants. Design Guidebook
An important consideration in the design of spacecraft for interplanetary missions is the compatibility of storage materials with the propellants. Serious problems can arise because many propellants are either extremely reactive or subject to catalytic decomposition, making the selection of proper materials of construction for propellant containment and control a critical requirement for the long-life applications. To aid in selecting materials and designing and evaluating various propulsion subsystems, available information on the compatibility of spacecraft materials with propellants of interest was compiled from literature searches and personal contacts. The compatibility of both metals and nonmetals with hydrazine, monomethyl hydrazine, nitrated hydrazine, and diborance fuels and nitrogen tetroxide, fluorine, oxygen difluoride, and Flox oxidizers was surveyed. These fuels and oxidizers encompass the wide variety of problems encountered in propellant storage. As such, they present worst case situations of the propellant affecting the material and the material affecting the propellant. This includes material attack, propellant decomposition, and the formation of clogging materials.
Uney, P. E.↗
The electrical power subsystem of the Pioneer F/G spacecraft.
The Pioneer F/G spacecraft is the first to use radioisotope thermoelectric generators (RTG's) for a long duration interplanetary mission. This paper describes the design of the spacecraft power subsystem which meets the unique requirements of such a mission. The primary power source consists of four SNAP 19 RTG's. The 4.2 volt dc outputs of the RTG's are inverted to higher voltage ac by four inverters which are connected in parallel at their outputs. A power control unit (PCU) regulates the ac output of the inverters such that the RTG's are operated at near maximum power voltage throughout the mission. The PCU also contains charge and discharge controls for a silver cadmium battery which supplements the RTG's if load requirements temporarily exceed RTG power output. Battery reliability is enhanced by overcharge and cell reversal protection electronics which are provided for each cell. Multiple, low voltage, regulated dc outputs which supply power to the spacecraft subsystems are provided by a central transformer-rectifier-filter unit (CTRF). The CTRF operates directly from the regulated ac bus.
Reppucci, G. M.↗
SEMMS - Understanding the solar electric multimission concept.
The feasibility of developing a solar electric multimission spacecraft (SEMMS) is examined with emphasis on understanding the effect of solar electric propulsion elements on a spacecraft system design. The applicability of Mariner, Viking, and thermoelectric outer planet spacecraft (TOPS) technologies to postulated mission/science objectives is investigated. A Mariner/Viking-based, modular spacecraft evolves which, with minimum modifications, is capable of performing a variety of interplanetary missions, including comet and asteroid rendezvous and orbit of Mercury, Jupiter, and Saturn. An early technology-evaluation flight is recommended to minimize the risk in subsequent missions.
Irace, W. R.↗
Spectral factorization in periodically time-varying systems and application to navigation problems.
Spectral factorization has been used previously to derive the steady-state solution of Kalman filtering equations without iteration for constant coefficient systems. The present work extends the spectral factorization algorithm to time-varying systems having periodic coefficient matrices for cases of both discrete and continuous systems. Time-consuming, expensive iterations of sequential covariance equations are not required to reach the final solution since this is an algebraic algorithm employing existing eigenvalue, eigenvector subroutines. The computer program incorporating the algorithm is suitable for sensitivity studies in formulating navigation and guidance strategies of low-thrust interplanetary missions. The determination of an optimum tracking pattern from an earth station is examined as an example.
Nishimura, T.↗
An analytical and experimental evaluation of shadow shields and their support members.
Review of the major results of an analytical and experimental program aimed at determining the potential effectiveness of shadow shields in minimizing radiant heat transfer into cryogenic propellant tanks on long-duration interplanetary missions, taking into account the thermal interaction between shields and their support structures. Analytical procedures are developed and applied that include the strut-shield interaction in predicting shadow shield performance. The results of experimental studies of the effects of configuration variables on the performance of a scale model of a shadow shield system are presented. The experimental results are used to verify the validity of analytical predictions. The results obtained show that: (1) shadow shields can be effective in reducing the heat transfer into cryogenic propellant tanks, and (2) the conductive heat transfer through supports can be reduced by selective surface coatings.
Stochl, R. J.↗
Natural environment design requirements for the Solar Electric Propulsion Stage (SEPS)
The natural environment design requirements for the solar electric propulsion stage are presented. Environment criteria for the SEP stage will cover earth orbital operations out to geosynchronous altitudes and also interplanetary missions including comet and asteroid missions.
Andrews, L. E.↗
Current technology in ion and electrothermal propulsion
The state of the art and projected developmental trends in the fields of ion and electrothermal propulsion systems intended for use in long and complex earth-orbital missions and interplanetary spacecraft missions are reviewed. The characteristics of existing thrust vectoring systems are outlined, together with data on the 5-cm and 8-cm electron bombardment thrusters, the cesium bombardment ion thruster, and the 8-cm, 15-cm, and 30-cm thruster using xenon propellant. The electrothermal ammonia system and the electrothermal hydrazine system are described, and the principles of propulsion system selection are examined.
Finke, R. C.↗
Analytic methods of orbit determination
This paper discusses several analytic models for predicting orbit determination performance during an interplanetary mission. Previously developed models for cruise radio tracking are reviewed and extended. Models for use with first radio and then optical tracking during approach are also developed. Comparison of the results with those obtained with full simulation models is emphasized. Several example problems using the analytic models are introduced to demonstrate the physical understanding possible with their employment.
Curkendall, D. W.↗
Conditioning of MVM '73 radio-tracking data
An extensive effort was undertaken to edit Mariner 10 radiometric tracking data. Interactive computer graphics were used for the first time by an interplanetary mission to detect blunder points and spurious signatures in the data. Interactive graphics improved the former process time by a factor of 10 to 20, while increasing reliability. S/X dual Doppler data was used for the first time to calibrate charged particles in the tracking medium. Application of the charged particle calibrations decreased the orbit determination error for a short data arc following the 16 March 1974 maneuver by about 80%. A new model was developed to calibrate the earth's troposphere with seasonal adjustments. The new model has a 2% accuracy and is 5 times better than the old model.
Koch, R. E.↗