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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 325 records · Page 18

Advanced EVA Capabilities: A Study for NASA's Revolutionary Aerospace Systems Concept Program

This report documents the results of a study carried out as part of NASA s Revolutionary Aerospace Systems Concepts Program examining the future technology needs of extravehicular activities (EVAs). The intent of this study is to produce a comprehensive report that identifies various design concepts for human-related advanced EVA systems necessary to achieve the goals of supporting future space exploration and development customers in free space and on planetary surfaces for space missions in the post-2020 timeframe. The design concepts studied and evaluated are not limited to anthropomorphic space suits, but include a wide range of human-enhancing EVA technologies as well as consideration of coordination and integration with advanced robotics. The goal of the study effort is to establish a baseline technology "road map" that identifies and describes an investment and technical development strategy, including recommendations that will lead to future enhanced synergistic human/robot EVA operations. The eventual use of this study effort is to focus evolving performance capabilities of various EVA system elements toward the goal of providing high performance human operational capabilities for a multitude of future space applications and destinations. The data collected for this study indicate a rich and diverse history of systems that have been developed to perform a variety of EVA tasks, indicating what is possible. However, the data gathered for this study also indicate a paucity of new concepts and technologies for advanced EVA missions - at least any that researchers are willing to discuss in this type of forum.

Hoffman, Stephen J.↗

Earth Observatory Satellite system definition study. Report no. 3: Design/cost tradeoff studies. Appendix E: EOS program supporting system. Part 1: System trade studies no. 1 through 8

The design requirements and associated cost impacts for using the space shuttle to deliver the Earth Observatory Satellite (EOS) are identified. The additional impact of achieving full compatibility for resupply and retrieval is considered. Based on the results of the analysis, it is concluded that the EOS-Shuttle compatibility can be realized with reasonable spacecraft weight and cost penalties. Inherent space shuttle capabilities are adequate to meet the requirements of all missions except E and F. Mission E (Tiros 0) may be accommodated by either an EOS orbit transfer capability or a tug. The tug appears to be the only viable approach to satisfying the mission F (SEOS) requirements.

Source record↗

Earth Observatory Satellite system definition study. Report no. 3: Design/cost tradeoff studies. Appendix E: EOS program supporting system trade data. Part 2: System trade studies no. 9 - 19

The relative merits of several international data acquisition (IDA) alternatives for the Earth Observatory Satellite (EOS) are established and rated on a cost effectiveness basis. The primary alternatives under consideration are: (1) direct transmission to foreign ground stations, (2) a wideband video tape recorder system for collection of foreign data and processing and distribution from the United States, and (3) a tracking and data relay satellite (TDRS) system for the relay of foreign data to the United States for processing and distribution. A requirements model is established for the analysis on the basis of the heaviest concentration of agricultural areas around the world. The model, the orbit path and the constraints of EOS and data volume summaries are presented. Alternative system descriptions and costs are given in addition to cost-performance summaries.

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The Advanced Orbiting Systems Testbed Program: Results to date

The Consultative Committee for Space Data Systems (CCSDS) Recommendations for Packet Telemetry (PT) and Advanced Orbiting Systems (AOS) propose standard solutions to data handling problems common to many types of space missions. The Recommendations address only space/ground and space/space data handling systems. Goddard Space Flight Center's (GSFC's) AOS Testbed (AOST) Program was initiated to better understand the Recommendations and their impact on real-world systems, and to examine the extended domain of ground/ground data handling systems. The results and products of the Program will reduce the uncertainties associated with the development of operational space and ground systems that implement the Recommendations.

Otranto, John F.↗

Earth orbital teleoperator manipulator system evaluation program

The performance of an orbital teleoperator system which includes small dextrous servicing manipulators to be used in satellite servicing was examined. System/operator performance testing was implemented and the results of a fine positioning control test using two different manipulator systems varying widely in manipulator configuration and control systems are presented. Fine position control is viewed as representing a fundamental requirement placed on manipulator control. The relationship of position control to more complex tasks which directly represent on-orbit servicing operations are also presented.

Kirkpatrick, M., III↗

Forward Skirt Structural Testing on the Space Launch System (SLS) Program

Introduction: (a) Structural testing was performed to evaluate Space Shuttle heritage forward skirts for use on the Space Launch System (SLS) program, (b) Testing was required because SLS loads are approximately 35% greater than shuttle loads; and (c) Two forwards skirts were tested to failure.

Lohrer, Joe↗

NASA’s Commercial Smallsat Data Acquisition (CSDA) Program Data System

The National Aeronautic and Space Administration (NASA) Commercial Smallsat Data Acquisition (CSDA) Program was established to identify, evaluate, and acquire data from commercial satellite companies that support and complement NASA’s Earth sciences missions and research goals. Since becoming a sustained program in 2020, CSDA has been developing a data system to provide scalable, efficient, continuous, and repeatable data management processes for all commercial data acquired by NASA. This includes providing access to commercial data to approved science investigators through NASA developed and vendor operated interfaces. As the commercial data user community and volume of data acquired by CSDA has grown, the team managing these data has adapted technologies and services to better address the data and information search, discovery, and access needs of the science user community. This presentation will provide an overview of CSDA Program data system activities including data availability, development of CSDA user interfaces, challenges in managing large-volume diverse datasets, and long-term data preservation activities to retain data for scientific reproducibility.

data management↗

Making automated computer program documentation a feature of total system design

It is pointed out that in large-scale computer software systems, program documents are too often fraught with errors, out of date, poorly written, and sometimes nonexistent in whole or in part. The means are described by which many of these typical system documentation problems were overcome in a large and dynamic software project. A systems approach was employed which encompassed such items as: (1) configuration management; (2) standards and conventions; (3) collection of program information into central data banks; (4) interaction among executive, compiler, central data banks, and configuration management; and (5) automatic documentation. A complete description of the overall system is given.

Wolf, A. W.↗

General Fluid System Simulation Program to Model Secondary Flows in Turbomachinery

The complexity and variety of turbomachinery flow circuits created a need for a general fluid system simulation program for test data anomaly resolution as well as design review. The objective of the paper is to present a computer program that has been developed to support Marshall Space Flight Center's turbomachinery internal flow analysis efforts. The computer program solves for the mass. energy and species conservation equation at each node and flow rate equation at each branch of the network by a novel numerical procedure which is a combination of both Newton-Ralphson and successive substitution method and uses a thermodynamic property program for computing real gas properties. A generalized, robust, modular, and 'user-friendly' computer program has been developed to model internal flow rates, pressures, temperatures, concentrations of gas mixtures and axial thrusts. The program can be used for any network for compressible and incompressible flows, choked flow, change of phase and gaseous mixturecs. The code has been validated by comparing the predictions with Space Shuttle Main Engine test data.

Majumdar, Alok K.↗

Multi-Node Modeling of Cryogenic Tank Pressurization System using Generalized Fluid System Simulation Program

This paper presents a multi-node model of autogenous pressurization of cryogenic propellant in a flight tank using the Generalized Fluid System Simulation Program (GFSSP), a general purpose flow network code developed at NASA/Marshall Space Flight Center. Tests were conducted to measure the pressure and temperatures at the various axial locations of the stratified ullage at 75% and 45% fill level. Liquid nitrogen was pressurized by gaseous nitrogen from a supply tank while the drain valve from the tank remained closed during the pressurization process. The ullage was discretized into 25 uniformly distributed nodes: 5 in the radial direction and 5 in the axial direction assuming the flow to be axisymmetric. Heat and mass transfer between the liquid and vapor has been modeled at the liquid vapor interface. Heat transfer between wall and vapor at the ullage has been accounted for by assuming heat transfer occurs by natural convection. The model also accounts for heat leak to the tank through the insulation and metal wall by heat conduction. The predicted pressures and temperatures are compared with the measured data.

Bandyopadhyay, Alak↗

Access 5 - Step 1: Human Systems Integration Program Plan (HSIPP)

This report describes the Human System Interface (HSI) analysis, design and test activities that will be performed to support the development of requirements and design guidelines to facilitate the incorporation of High Altitude Long Endurance (HALE) Remotely Operated Aircraft (ROA) at or above FL400 in the National Airspace System (NAS). These activities are required to support the design and development of safe, effective and reliable ROA operator and ATC interfaces. This plan focuses on the activities to be completed for Step 1 of the ACCESS 5 program. Updates to this document will be made for each of the four ACCESS 5 program steps.

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Large space systems technology program

Technical challenges of shuttle-era large space systems include the development of space-configured spacecraft concepts, compatibility with the space transportation system, and cost effectiveness. The objectives and organization of NASA's large space structures program are outlined and program elements are discussed. The technology for the offset wrap-rip and the maypole (hoop/column) antenna concepts are discussed as well as analysis techniques for predicting the electromagnetic performance of a broad class of large reflectors. Deployable systems, assembly methods, and modular control systems for space platforms are described. Assembly equipment and devices, surface sensors and shape control, control and stabilization, and integrated analysis and design are also considered.

James, R. L., Jr.↗

Modeling of Compressible Flow with Friction and Heat Transfer Using the Generalized Fluid System Simulation Program (GFSSP)

The present paper describes the verification and validation of a quasi one-dimensional pressure based finite volume algorithm, implemented in Generalized Fluid System Simulation Program (GFSSP), for predicting compressible flow with friction, heat transfer and area change. The numerical predictions were compared with two classical solutions of compressible flow, i.e. Fanno and Rayleigh flow. Fanno flow provides an analytical solution of compressible flow in a long slender pipe where incoming subsonic flow can be choked due to friction. On the other hand, Raleigh flow provides analytical solution of frictionless compressible flow with heat transfer where incoming subsonic flow can be choked at the outlet boundary with heat addition to the control volume. Nonuniform grid distribution improves the accuracy of numerical prediction. A benchmark numerical solution of compressible flow in a converging-diverging nozzle with friction and heat transfer has been developed to verify GFSSP's numerical predictions. The numerical predictions compare favorably in all cases.

Bandyopadhyay, Alak↗

A digital computer program for the dynamic interaction simulation of controls and structure (DISCOS), volume 1

A theoretical development and associated digital computer program system for the dynamic simulation and stability analysis of passive and actively controlled spacecraft are presented. The dynamic system (spacecraft) is modeled as an assembly of rigid and/or flexible bodies not necessarily in a topological tree configuration. The computer program system is used to investigate total system dynamic characteristics, including interaction effects between rigid and/or flexible bodies, control systems, and a wide range of environmental loadings. In addition, the program system is used for designing attitude control systems and for evaluating total dynamic system performance, including time domain response and frequency domain stability analyses.

Bodley, C. S.↗