Search NASA⌕ Search

SEARCH · Search NASA

Results for “Space Processing”

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.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 181 records · Page 10

Space Shuttle processing - A case study in artificial intelligence

A scheduling system incorporating AI is described and applied to the automated processing of the Space Shuttle. The unique problem of addressing the temporal, resource, and orbiter-configuration requirements of shuttle processing is described with comparisons to traditional project management for manufacturing processes. The present scheduling system is developed to handle the late inputs and complex programs that characterize shuttle processing by incorporating fixed preemptive scheduling, constraint-based simulated annealing, and the characteristics of an 'anytime' algorithm. The Space-Shuttle processing environment is modeled with 500 activities broken down into 4000 subtasks and with 1600 temporal constraints, 8000 resource constraints, and 3900 state requirements. The algorithm is shown to scale to very large problems and maintain anytime characteristics suggesting that an automated scheduling process is achievable and potentially cost-effective.

Mollikarimi, Cindy↗

A Comparative Study of Measuring Devices Used During Space Shuttle Processing for Inside Diameters

During Space Shuttle processing, discrepancies between vehicle dimensions and per print dimensions determine if a part should be refurbished, replaced or accepted "as-is." The engineer's job is to address each discrepancy by choosing the most accurate procedure and tool available, sometimes with up to ten thousands of an inch tolerance. Four methods of measurement are commonly used at the Kennedy Space Center: 1) caliper, 2) mold impressions, 3) optical comparator, 4) dial bore gage. During a problem report evaluation, uncertainty arose between methods after measuring diameters with variations of up to 0.0004" inches. The results showed that computer based measuring devices are extremely accurate, but when human factor is involved in determining points of reference, the results may vary widely compared to more traditional methods. iv

Rodriguez, Antonio↗

Materials processing in space - New challenges for industry

A summary is presented of NASA's activity in materials research in zero-g. Very simple experiments to determine the effects of zero-g upon solidification processes, upon heat flow, convection and mass transport, and upon the separation of biological cells were conducted during three Apollo flights. The investigations were continued in a series of experiments conducted on Skylab. The experiments provided data on a wide range of space-processing topics. The various tests and the results obtained in them are discussed. Attention is also given to experiments planned for the Apollo-Soyuz experiment, studies to be conducted with the aid of sounding rockets, and an evaluation of the possibilities provided by space processing for industry.

Bredt, J. H.↗

NASA Space Shuttle Processing

This viewgraph presentation reviews NASA's Space Shuttle Processing at Kennedy Space Center. A demonstration of the Space Shuttle silica tiles, a description of its High Temperature Reusable Surface Insulation (HRSI), tile inspections, and tile replacement demonstrations are also presented.

Andruske, Linda Lee↗

Macro Level Simulation Model Of Space Shuttle Processing

The contents include: 1) Space Shuttle Processing Simulation Model; 2) Knowledge Acquisition; 3) Simulation Input Analysis; 4) Model Applications in Current Shuttle Environment; and 5) Model Applications for Future Reusable Launch Vehicles (RLV's). This paper is presented in viewgraph form.

Source record↗

Conditions and constraints of food processing in space

Requirements and constraints of food processing in space include a balanced diet, food variety, stability for storage, hardware weight and volume, plant performance, build-up of microorganisms, and waste processing. Lunar, Martian, and space station environmental conditions include variations in atmosphere, day length, temperature, gravity, magnetic field, and radiation environment. Weightlessness affects fluid behavior, heat transfer, and mass transfer. Concerns about microbial behavior include survival on Martian and lunar surfaces and in enclosed environments. Many present technologies can be adapted to meet space conditions.

NASA Discipline Life Support Systems↗

Automation of vehicle processing at Space Station Freedom

A methodology for applying the Kennedy Space Center vehicle processing experience to similar operations at Space Station Freedom is described. First, the required on-orbit processing tasks are identified. These tasks are then evaluated for automation suitability, and robotic manipulator and artificial intelligence technologies are investigated to automate selected physical and cognitive tasks. Effects on processing times, extra-vehicular activity savings, and required resources for incorporating these automation enhancements are identified. Results of the following case studies are included: Phobos Gateway Vehicle On-Orbit Assembly and Launch, Lunar Evolution Vehicle On-Orbit Refurbishment, and Mars Mission Vehicle On-Orbit Assembly and Launch.

Vargo, Rick↗

A SLAM II simulation model for analyzing space station mission processing requirements

Space station mission processing is modeled via the SLAM 2 simulation language on an IBM 4381 mainframe and an IBM PC microcomputer with 620K RAM, two double-sided disk drives and an 8087 coprocessor chip. Using a time phased mission (payload) schedule and parameters associated with the mission, orbiter (space shuttle) and ground facility databases, estimates for ground facility utilization are computed. Simulation output associated with the science and applications database is used to assess alternative mission schedules.

Linton, D. G.↗

Selective Deposition and Fusion of AISI 316L: An Additive Manufacturing Process for Space Environments via Direct Ink Writing and Laser Processing

Unlocking the potential of additive manufacturing (AM) for space exploration hinges on overcoming key challenges, notably the ability to manufacture or repair parts on-site during exploration missions with consideration of quality, feedstock utilization, and challenges involved in microgravity environments. While there are multiple efforts to investigate the use of existing metal AM processes such as powder bed fusion (PBF), directed energy deposition (DED), and filament-based material extrusion, each process comes with a different set of challenges in space environments. Here, in this work, we introduce a new AM method that integrates the benefits of direct ink writing (DIW) to selectively deposit metallic pastes with laser-based processing to locally debind and subsequently melt and fuse metal powder, layer by layer, enabling the manufacturing of AISI 316L samples with densities exceeding 99.0%. The impact of process parameters on single-track dimensions, surface morphology, and porosity was characterized. The efficacy of laser debinding was assessed via secondary-ion mass spectrometry, permitting the carbon content to be estimated at 0.0152%, which is safely below the acceptable limit (0.03 wt%) for AISI 316L.

36 MATERIALS SCIENCE↗

Materials processing in space, 1980 science planning document

The scientific aspects of the Materials Processing in Space program are described with emphasis on the major categories of interest: (1) crystal growth; (2) solidification of metals, alloys, and composites; (3) fluids and chemical processes; (4) containerless processing, glasses, and refractories; (5) ultrahigh vacuum processes; and (6) bioprocessing. An index is provided for each of these areas. The possible contributions that materials science experiments in space can make to the various disciplines are summarized, and the necessity for performing experiments in space is justified. What has been learned from previous experiments relating to space processing, current investigations, and remaining issues that require resolution are discussed. Recommendations for the future direction of the program are included.

Naumann, R. J.↗

Convection phenomena in low-gravity processing - The GTE GaAs space experiment

A numerical model for the proposed GTE GaAs space experiment is presented. The model includes the actual ampule design and the experimentally obtained furnace thermal profiles. Results are presented based on both the traditional steady-state models and on fully time dependent simulations. It is demonstrated that the commonly presumed axisymmetric flows in numerical studies are physically accurate only when the local gravitational acceleration vector is parallel to the ampules's axis. Other gravitational orientations result in nontrivial three-dimensional flows which must be resolved using full three-dimensional models. Implications of the resulting flow and thermal fields on the growing crystal at conditions available during space processing are also discussed.

Arnold, W. A.↗

National Space Transportation System Reference. Volume 2: Operations

An overview of the Space Transportation System is presented in which aspects of the program operations are discussed. The various mission preparation and prelaunch operations are described including astronaut selection and training, Space Shuttle processing, Space Shuttle integration and rollout, Complex 39 launch pad facilities, and Space Shuttle cargo processing. Also, launch and flight operations and space tracking and data acquisition are described along with the mission control and payload operations control center. In addition, landing, postlanding, and solid rocket booster retrieval operations are summarized. Space Shuttle program management is described and Space Shuttle mission summaries and chronologies are presented. A glossary of acronyms and abbreviations are provided.

Source record↗

Optical processing and Space Station automation

Optical information processing research aimed at Space Station automation applications is reviewed. The emphasis of the NASA Ames Research Center program is on intelligent optical pattern recognition and optical control processing. Attention is given to the primary functions of an overall scene understanding system: distortion-invariant optical feature generation, dimensionality reduction, object classification, and contextual information processing. A method of using synthetic discriminant functions to facilitate learning in a high-speed optical correlator is described. A discussion is presented of candidate analog and digital architectures for the optical implementation of state-estimation algorithms needed for the control of high-dimension dynamic systems. The multivariate system chosen for the optical control technology demonstration - a segmented, adaptive mirror and interferometrically based wavefront sensor - is also described.

Ennis, D. J.↗

Metallurgical processing in space

Research in metallurgical processing to study the effects of reduced gravity started with Apollo 14 and advanced with Skylab. Experiments provided specimens for analysis which solidified while constrained and while freely floating, which contained a mixture of normally immiscible materials, demonstrated enhanced capillary flow, solubility and ordered growth of a directionally solidified eutectic. The smaller, equiaxed grain structure obtained in reduced gravity compared to the larger, elongated grains obtained in one gravity indicate a difference in convection due to gravity in constrained solidification. Freely floating nickel alloy specimens showing metallic gas evolution at low pressure and reduced gravity suggest reduced pressure reactions which cannot occur on earth even in high vacuum chambers due to the hydrostatic head in the molten metal. Directionally solidified eutectics showed fewer termination defects when grown in reduced gravity. These are a few of the differences observed due to reduced gravity which could have important consequences on the future of metallurgy. In this paper we attempt to correlate the results of several Skylab solidification experiments.

Mckannan, E. C.↗

Space Weathering of Apollo 16 Sample 62255: Lunar Rocks as Witness Plates for Deciphering Regolith Formation Processes

Space weathering, or alteration that occurs at the surfaces of materials exposed directly to space, has been one of the primary areas of focus of lunar studies for the past several years. It is caused by processes such as micrometeorite impacts and solar wind bombardment, and effects can include microcraters, spall zones, and vapor deposits. Much of the recent work on space weathering has been concentrated on nanoscale features, especially the amorphous rims commonly found on individual lunar soil grains. The rims typically contain nanophase Fe metal globules, which, along with Fe metal globules in agglutinates, have a profound effect on optical properties of lunar soils. The nanophase metallic iron globules cause the characteristic optical changes (reddening and darkening) found in mature lunar soils.

Wentworth, S. J.↗

High-Resolution and Analytical TEM Investigation of Space Radiation Processing Effects in Primitive Solar System Materials and Airless Planetary Surface Environments

Energetic ions present in the diverse plasma conditions in space play a significant role in the formation and modification of solid phases found in environments ranging from the interstellar medium (ISM) to the surfaces of airless bodies such as asteroids and the Moon. These effects are often referred to as space radiation processing, a term that encompasses changes induced in natural space-exposed materials that may be only structural, such as in radiation-induced amorphization, or may involve ion-induced nanoscale to microscale chemical changes, as occurs in preferential sputtering and ion-beam mixing. Ion sputtering in general may also be responsible for partial or complete erosion of space exposed materials, in some instances possibly bringing about the complete destruction of free-floating solid grains in the ISM or in circumstellar nebular dust clouds. We report here on two examples of the application of high-resolution and analytical transmission electron microscopy (TEM) to problems in space radiation processing. The first problem concerns the role of space radiation processing in controlling the overall fate of Fe sulfides as hosts for sulfur in the ISM. The second problem concerns the known, but as yet poorly quantified, role of space radiation processing in lunar space weathering.

Christoffersen, R.↗

Materials processing in space; Proceedings of the Special Conference, Cincinnati, OH, May 4, 5, 1982

An international review of materials processing in space is provided, taking into account the NASA materials processing in space program, European activities in the field of microgravity research, and Japanese material processing tests in space. The subjects considered are related to materials processing in a microgravity environment, industrial and university applications and involvement, and challenges and prospectives of microgravity research in space. Attention is given to a review of the containerless processing technologies and facilities, glass research in space, bubble behavior in molten glass in a temperature gradient, semiconductor crystal growth and segregation problems on earth and space, seeded crystal growth of pseudobinary systems with large liquidus-solidus separation, avenues and incentives for commercial use of a low-gravity environment, and the Universities Space Research Association and its role in the materials processing in space program.

Dunbar, B. J.↗

Materials processing in space overview

Projects involved in the materials processing in space program are listed. The research task involved in each project and the space hardware required for projects in the physical and chemical sciences and in materials processing are summarized.

Oran, W.↗