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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 19 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1991

In-space technology flight experiments: Middeck 0-gravity Dynamics Experiment (MODE) and Middeck Active Control Experiment (MACE)

The topics addressed are covered in viewgraph form. The objective of the Middeck 0-gravity Dynamics Experiment (MODE) programs is to study gravity dependent nonlinearities associated with fluid slosh and truss structure dynamics. MODE provides a reusable facility for on-orbit dynamics testing of small scale test articles in the shirt sleeve environment on the Shuttle middeck. Flight program objective of Middeck Active Control Experiment (MACE) is to study gravity effects on the performance and stability of controlled structures.

Venneri, Samuel L.↗
NASA NTRS1993

The middeck 0-gravity dynamics experiment

The Middeck 0-Gravity Dynamics Experiment (MODE), flown onboard the Shuttle STS-48 Mission, consists of three major elements: the Experiment Support Module, a dynamics test bed providing computer experiment control, analog signal conditioning, power conditioning, an operator interface consisting of a keypad and display, experiment electrical and thermal control, and archival data storage: the Fluid Test Article assembly, used to investigate the dynamics of fluid-structure interaction in 0-gravity; and the Structural Test Article for investigating the open-loop dynamics of structures in 0-gravity. Deployable, erectable, and rotary modules were assembled to form three one- and two-dimensional structures, in which variations in bracing wire and rotary joint preload could be introduced. Change in linear modal parameters as well as the change in nonlinear nature of the response is examined. Trends in modal parameters are presented as a function of force amplitude, joint preload, and ambient gravity. An experimental study of the lateral slosh behavior of contained fluids is also presented. A comparison of the measured earth and space results identifies and highlights the effects of gravity on the linear and nonlinear slosh behavior of these fluids.

Crawley, Edward F.↗
NASA NTRS1995

The Photogrammetric Appendage Structural Dynamics Experiment

The Photogrammetric Appendage Structural Dynamics Experiment (PASDE) is a Hitchhiker payload scheduled to fly as part of the International Space Station (ISS) Phase-1 flight program to the Russian Space Station Mir. The objective of the first flight of PASDE on STS-74 is to obtain video images of the Mir Kvant-2 solar array response to various structural dynamic excitation events. This experiment will demonstrate the use of photogrammetric techniques for on-orbit structural dynamics measurements. Photogrammetric measurements will provide a low cost alternative to appendage mounted accelerometers to the ISS program. The PASDE experiment hardware consists of three instruments each containing two video cameras, two video tape recorders, a modified video signal time inserter, and associated avionics boxes. The instruments were designed and built at the NASA Langley Research Center, and are integrated into standard Hitchhiker canisters at the NASA Goddard Space Flight Center. The Hitchhiker canisters are then installed into the Space Shuttle cargo bay in locations selected to achieve good video coverage and photogrammetric geometry. The measurement resolution of the instruments is expected to be on the order of 0.25 cm (0.1 in.).

Gilbert, Michael G.↗
NASA NTRS1996

STS-74/Mir photogrammetric appendage structural dynamics experiment

The Photogrammetric Appendage Structural Dynamics Experiment (PASDE) is an International Space Station (ISS) Phase-1 risk mitigation experiment. Phase-1 experiments are performed during docking missions of the U.S. Space Shuttle to the Russian Space Station Mir. The purpose of the experiment is to demonstrate the use of photogrammetric techniques for determination of structural dynamic mode parameters of solar arrays and other spacecraft appendages. Photogrammetric techniques are a low cost alternative to appendage mounted accelerometers for the ISS program. The objective of the first flight of PASDE, on STS-74 in November 1995, was to obtain video images of Mir Kvant-2 solar array response to various structural dynamic excitation events. More than 113 minutes of high quality structural response video data was collected during the mission. The PASDE experiment hardware consisted of three instruments each containing two video cameras, two video tape recorders, a modified video signal time inserter, and associated avionics boxes. The instruments were designed, fabricated, and tested at the NASA Langley Research Center in eight months. The flight hardware was integrated into standard Hitchhiker canisters at the NASA Goddard Space Flight Center and then installed into the Space Shuttle cargo bay in locations selected to achieve good video coverage and photogrammetric geometry.

Welch, Sharon S.↗
NASA NTRS1995

Simulation of the photogrammetric appendage structural dynamics experiment

The Photogrammetric Appendage Structural Dynamics Experiment (PASDE) uses six video cameras in the Space Shuttle cargo bay to measure vibration of the Russian Mir space station Kvant-ll solar array. It occurs on Shuttle/Mir docking mission STS-74 scheduled for launch in November 1995. The objective of PASDE is to demonstrate photogrammetric technology for measuring 'untargeted' spacecraft appendage structural dynamics. This paper discusses a pre-flight simulation test conducted in July 1995, focusing on the image processing aspects. The flight camera system recorded vibrations of a full-scale structural test article having grids of white lines on black background, similar in appearance to the Mir solar array. Using image correlation analysis, line intersections on the structure are tracked in the video recordings to resolutions of less than 0.1 pixel. Calibration and merging of multiple camera views generated 3-dimensional displacements from which structural modal parameters are then obtained.

Pappa, Richard S.↗
NASA NTRS1991

The Surface Wave Dynamics Experiment (SWADE)

The Surface Wave Dynamics Experiment is designed to provide the basic data needed to understand the wind-wave interactions in the open ocean. During the period of October 1990 through March 1991 two discus, four meteorological buoys, and several other specialized buoys will collect continuous in-situ data. During three intensive periods of study, several aircraft and an airship will collect synoptic data from the study area in the Atlantic east of the Wallops Flight Facility. Data from the buoys will be collected by aircraft and ARGOS data links. Instrumentation descriptions as well as preliminary data from the first intensive study period are presented.

Mollo-Christensen, Erik↗
NASA NTRS1973

Gravity-gradient dynamics experiments performed in orbit utilizing the Radio Astronomy Explorer (RAE-1) spacecraft

Six dynamic experiments were performed in earth orbit utilizing the RAE spacecraft in order to test the accuracy of the mathematical model of RAE dynamics. The spacecraft consisted of four flexible antenna booms, mounted on a rigid cylindrical spacecraft hub at center, for measuring radio emissions from extraterrestrial sources. Attitude control of the gravity stabilized spacecraft was tested by using damper clamping, single lower leading boom operations, and double lower boom operations. Results and conclusions of the in-orbit dynamic experiments proved the accuracy of the analytic techniques used to model RAE dynamical behavior.

Walden, H.↗
NASA NTRS1985

Definition phase for thermal ion dynamics experiment for OPEN

The Thermal Ion Dynamics Experiment (TIDE) combines differential measurements of angle, energy, and mass to determine the detailed distribution function of low energy magnetospheric ions in the range of 0 to 100 eV. Goals included designing a 1 sq cm entrance aperture, minimizing trajectory divergence at exist aperture, and minimizing internal scattering. Design parameters were used to construct the test model.

Sharp, W. E.↗
NASA NTRS1986

Solar array flight dynamic experiment

The purpose of the Solar Array Flight Dynamic Experiment (SAFDE) is to demonstrate the feasibility of on-orbit measurement and ground processing of large space structures dynamic characteristics. Test definition or verification provides the dynamic characteristic accuracy required for control systems use. An illumination/measurement system was developed to fly on space shuttle flight STS-31D. The system was designed to dynamically evaluate a large solar array called the Solar Array Flight Experiment (SAFE) that had been scheduled for this flight. The SAFDE system consisted of a set of laser diode illuminators, retroreflective targets, an intelligent star tracker receiver and the associated equipment to power, condition, and record the results. In six tests on STS-41D, data was successfully acquired from 18 retroreflector targets and ground processed, post flight, to define the solar array's dynamic characteristic. The flight experiment proved the viability of on-orbit test definition of large space structures dynamic characteristics. Future large space structures controllability should be greatly enhanced by this capability.

Schock, R. W.↗
NASA NTRS1987

Solar array flight dynamic experiment

The purpose of the Solar Array Flight Dynamic Experiment (SAFDE) is to demonstrate the feasibility of on-orbit measurement and ground processing of large space structures' dynamic characteristics. Test definition or verification provides the dynamic characteristic accuracy required for control systems use. An illumination/measurement system was developed to fly on space shuttle flight STS-41D. The system was designed to dynamically evaluate a large solar array called the Solar Array Flight Experiment (SAFE) that had been scheduled for this flight. The SAFDE system consisted of a set of laser diode illuminators, retroreflective targets, an intelligent star tracker receiver and the associated equipment to power, condition, and record the results. In six tests on STS-41D, data was successfully acquired from 18 retroreflector targets and ground processed, post flight, to define the solar array's dynamic characteristic. The flight experiment proved the viability of on-orbit test definition of large space structures dynamic characteristics. Future large space structures controllability should be greatly enhanced by this capability.

Schock, Richard W.↗
NASA NTRS1986

Solar array flight dynamic experiment

The purpose of the Solar Array Flight Dynamic Experiment (SAFDE) is to demonstrate the feasibility of on-orbit measurement and ground processing of large space structures dynamic characteristics. Test definition or verification provides the dynamic characteristic accuracy required for control systems use. An illumination/measurement system was developed to fly on Space Shuttle flight STS-31D. The system was designed to dynamically evaluate a large solar array called the Solar Array Flight Experiment (SAFE) that had been scheduled for this flight. The SAFDE system consisted of a set of laser diode illuminators, retroreflective targets, an intelligent star tracker receiver and the associated equipment to power, condition, and record the results. In six tests on STS-41D, data was successfully acquired from 18 retroreflector targets and ground processed, post flight, to define the solar array's dynamic characteristic. The flight experiment proved the viability of on-orbit test definition of large space structures dynamic characteristics. Future large space structures controllability should be greatly enhanced by this capability.

Schock, Richard W.↗
NASA NTRS1992

Middeck 0-gravity dynamics experiment: Fluid slosh experiments

Viewgraphs on the Middeck 0-gravity Dynamics Experiment fluid slosh experiments are presented. Graphs of frequency versus planar slosh force and planar slosh force phase angle are provided for the following conditions: silicone oil in a flat bottom tank; silicon oil in a 3.1 cm diameter flat bottom tank; water in a flat bottom tank for earth; and water in a 3.1 cm diameter flat bottom tank.

Vanschoor, Marthinus C.↗
NASA NTRS1991

Middeck 0-gravity Dynamics Experiment (MODE)

Viewgraphs on Middeck 0-gravity Dynamics Experiment (MODE) are presented. Topics covered include: MODE and its rationale; program objectives; truss structures; contained fluids; experimental design for structures and contained fluids; modeling approach; and progress to date.

Vanschoor, Marthinus C.↗
NASA NTRS1993

Results from the Middeck 0-gravity Dynamics Experiment

The experimental results of the Middick Zero-gravity Dynamics Experiment (MODE) are presented. MODE investigated the dynamics of two key spacecraft components; contained fluids and jointed truss structures. The change in the lateral slosh behavior of contained fluids and the changes in the modal parameters of space structural test articles from one- to zero-gravity were studied. The experimental apparatus used to determine the dynamic characteristics is described. For the MODE fluid experiments, the forced response characteristics of silicone oil and distilled water in cylinder tanks with either a flat or spherical bottom are reported and discussed. A comparison of the measured earth and space results identifies and highlights the effects of gravity on the linear and nonlinear slosh behavior of these fluids. For the MODE structural experiments, an analytic and experimental study is presented. Deployable, erectable, and rotary modules were assembled to form three one- and two-dimensional structures in which variations in bracing wire and rotary joint preload could be introduced. Analysis is compared with ground experimental measurements made on a spring/wire suspension system with a nominal plunge frequency of one Hertz, and with measurements made on the Shuttle middeck. The degree of change in linear modal parameters as well as the change in nonlinear nature of the response is examined. Trends in modal parameters are presented as a function of force amplitude, joint preload, and ambient gravity level.

Van Schoor, M. C.↗
NASA NTRS1992

The Middeck 0-gravity Dynamics Experiment (MODE)

Viewgraphs on the middeck 0-gravity dynamics experiment (MODE) are presented. Topics covered include: MODE flight hardware elements; MODE science objectives; MODE team; flight operations; and summary.

Crawley, Edward F.↗
NASA NTRS1995

The Thermal Ion Dynamics Experiment and Plasma Source Instrument

The Thermal Ion Dynamics Experiment (TIDE) and the Plasma Source Instrument (PSI) have been developed in response to the requirements of the ISTP Program for three-dimensional (3D) plasma composition measurements capable of tracking the circulation of low-energy (0-500 eV) plasma through the polar magnetosphere. This plasma is composed of penetrating magnetosheath and escaping ionospheric components. It is in part lost to the downstream solar wind and in part recirculated within the magnetosphere, participating in the formation of the diamagnetic hot plasma sheet and ring current plasma populations. Significant obstacles which have previously made this task impossible include the low density and energy of the outflowing ionospheric plasma plume and the positive spacecraft floating potentials which exclude the lowest-energy plasma from detection on ordinary spacecraft. Based on a unique combination of focusing electrostatic ion optics and time of flight detection and mass analysis, TIDE provides the sensitivity (seven apertures of about 1 cm squared effective area each) and angular resolution (6 x 18 degrees) required for this purpose. PSI produces a low energy plasma locally at the POLAR spacecraft that provides the ion current required to balance the photoelectron current, along with a low temperature electron population, regulating the spacecraft potential slightly positive relative to the space plasma. TIDE/PSI will: (a) measure the density and flow fields of the solar and terrestrial plasmas within the high polar cap and magnetospheric lobes; (b) quantify the extent to which ionospheric and solar ions are recirculated within the distant magnetotail neutral sheet or lost to the distant tail and solar wind; (c) investigate the mass-dependent degree energization of these plasmas by measuring their thermodynamic properties; (d) investigate the relative roles of ionosphere and solar wind as sources of plasma to the plasma sheet and ring current.

Moore, T. E.↗
NASA NTRS1997

STS-74/Mir Photogrammetric Appendage Structural Dynamics Experiment Preliminary Data Analysis

The Photogrammetric Appendage Structural Dynamics Experiment was designed, developed, and flown to demonstrate and prove measurement of the structural vibration response of a Russian Space Station Mir solar array using photogrammetric methods. The experiment flew on the STS-74 Space Shuttle mission to Mir in November 1995 and obtained video imagery of solar array structural response to various excitation events. The video imagery has been digitized and triangulated to obtain response time history data at discrete points on the solar array. This data has been further processed using the Eigensystem Realization Algorithm modal identification technique to determine the natural vibration frequencies, damping, and mode shapes of the solar array. The results demonstrate that photogrammetric measurement of articulating, non-optically targeted, flexible solar arrays and appendages is a viable, low-cost measurement option for the International Space Station.

Gilbert, Michael G.↗