Search NASA⌕ Search

SEARCH · Search NASA

Results for “modular approach”

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 73 records · Page 4

Requirements and concepts for space-processing payloads

The definition of facilities which will serve the research needs of a large group of users is given. These facilities (payloads) are derived by several combinations of items from a large inventory of modular, reusable, research equipment which enables ready response to many flight opportunities. Workable concepts were prepared and submitted to the Spacelab design activity. These designs permit the flying of either partial or dedicated payloads. The technical integrity of the modular approach to payload design/integration and the utility of commercial equipment technology are also discussed.

Taylor, K. R.↗

Escort: A data acquisition and display system to support research testing

Primarily designed to acquire data at steady state test conditions, the system can also monitor slow transients such as those generated in moving to a new test condition. The system configuration makes use of a microcomputer at the test site which acts as a communications multiplexer between the measurement and display devices and a centrally located minicomputer. A variety of measurement and display devices are supported using a modular approach. This allows each system to be configured with the proper combination of devices to meet the specific test requirements, while still leaving the option to add special interfaces when needed. Centralization of the minicomputer improves utilization through sharing. The creation of a pool of minis to provide data acquisition and display services to a variable number of running tests also offers other important advantages.

Miller, R. L.↗

High efficiency ion beam accelerator system

An ion accelerator system that successfully combines geometrical and electrostatic focusing principles is presented. This accelerator system uses thin, concave, multiple-hole, closely spaced graphite screen and focusing grids which are coupled to single slot accelerator and decelerator grids to provide high ion extraction efficiency and good focusing. Tests with the system showed a substantial improvement in ion beam current density and collimation as compared with a Pierce electrode configuration. Durability of the thin graphite screen and focusing grids has been proven, and tests are being performed to determine the minimum screen and focusing grid spacing and thickness required to extract the maximum reliable beam current density. Compared with present neutral beam injector accelerator systems, this one has more efficient ion extraction, easier grid alignment, easier fabrication, a less cumbersome design, and the capacity to be constructed in a modular fashion. Conceptual neutral beam injector designs using this modular approach have electrostatic beam deflection plates downstream of each module.

Aston, G.↗

Planar-Wing Flutter Analysis

Flutter Analysis System, FAST, is group of five programs that perform flutter analysis of single planar wing. Each program performs certain portions of flutter analysis and may be run sequentially or individually. Modular approach is very versatile and flexible. FAST uses natural vibration modes as input data and performs conventional V-g solution.

Desmarais, R. N.↗

Modular antenna design study

The mechanical design of a modular antenna concept was developed sufficiently to allow manufacture of a working demonstration model of a module, to predict mass properties, and to make performance estimates for antenna reflectors composed of these modules. The primary features of this concept are: (1) each module is an autonomous structural element which can be attached to adjacent modules through a three point connection; (2) the upper surface is a folding hexagonal truss plate mechanism which serves as the supporting structure for a reflective surface; and (3) the entire truss and surface can be folded into a cylindrical envelope in which all truss elements are essentially parallel. The kinematic studies and engineering demonstration model fully verified the deployment kinematics, stowing philosophy, and deployment sequencing for large antenna modules. It was established that such modules can be stowed in packages as small as 25 cm in diameter, using 1.27 cm diameter structural tubes. The development activity indicates that this deployable modular approach towards building large structures in space will support erection of 450 m apertures for operation up to 3 GHz with a single space shuttle flight.

Ribble, J. W.↗

System architecture study of an orbital GPS user terminal

The generic RF and applications processing requirements for a GPS orbital navigator are considered. A line of demarcation between dedicated analog hardware, and software/processor implementation, maximizing the latter is discussed. A modular approach to R/PA design which permits several varieties of receiver to be constructed from basic components is described. It is a basic conclusion that software signal processing of the output of the baseband correlator is the best choice of transition from analog to digital signal processing. High performance sets requiring multiple channels are developed from a generic design by replicating the RF processing segment, and modifying the applications software to provide enhanced state propagation and estimation.

Martin, D. P.↗

Computational models for the analysis/design of hypersonic scramjet components. I - Combustor and nozzle models

An overview of computational models developed for the complete, design-oriented analysis of a scramjet propulsion system is provided. The modular approach taken involves the use of different PNS models to analyze the individual propulsion system components. The external compression and internal inlet flowfields are analyzed by the SCRAMP and SCRINT components discussed in Part II of this paper. The combustor is analyzed by the SCORCH code which is based upon SPLITP PNS pressure-split methodology formulated by Dash and Sinha. The nozzle is analyzed by the SCHNOZ code which is based upon SCIPVIS PNS shock-capturing methodology formulated by Dash and Wolf. The current status of these models, previous developments leading to this status, and, progress towards future hybrid and 3D versions are discussed in this paper.

Dash, S. M.↗

Fast-Polynomial-Transform Program

Computer program uses fast-polynomial-transformation (FPT) algorithm applicable to two-dimensional mathematical convolutions. Two-dimensional cyclic convolutions converted to one-dimensional convolutions in polynomial rings. Program decomposes cyclic polynomials into polynomial convolutions of same length. Only FPT's and fast Fourier transforms of same length required. Modular approach saves computional resources. Program written in C.

Truong, T. K.↗

Development of the Imaging Spectrometer for Shuttle and space platform applications

The concept of the Imaging Spectrometer is becoming established as a major new thrust in remote sensing of the earth. A future step will be the Shuttle Imaging Spectrometer (SISEX) currently planned for a 1990 flight. This paper describes the current state of development of SISEX, including the development of a modular concept which will allow major elements of SISEX to be used on NASA's Space platform, the Earth Observing System. This modular approach is expected to result in a substantial overall cost saving.

Herring, Mark↗

A framework for real-time distributed expert systems: On-orbit spacecraft fault diagnosis, monitoring and control

Control of on-orbit operation of a spacecraft requires retention and application of special purpose, often unique, knowledge of equipment and procedures. Real-time distributed expert systems (RTDES) permit a modular approach to a complex application such as on-orbit spacecraft support. One aspect of a human-machine system that lends itself to the application of RTDES is the function of satellite/mission controllers - the next logical step toward the creation of truly autonomous spacecraft systems. This system application is described.

Mullikin, Richard L.↗

Transonic Navier-Stokes computations of strake-generated vortex interactions for a fighter-like configuration

Transonic Euler/Navier-Stokes computations are accomplished for wing-body flow fields using a computer program called Transonic Navier-Stokes (TNS). The wing-body grids are generated using a program called ZONER, which subdivides a coarse grid about a fighter-like aircraft configuration into smaller zones, which are tailored to local grid requirements. These zones can be either finely clustered for capture of viscous effects, or coarsely clustered for inviscid portions of the flow field. Different equation sets may be solved in the different zone types. This modular approach also affords the opportunity to modify a local region of the grid without recomputing the global grid. This capability speeds up the design optimization process when quick modifications to the geometry definition are desired. The solution algorithm embodied in TNS is implicit, and is capable of capturing pressure gradients associated with shocks. The algebraic turbulence model employed has proven adequate for viscous interactions with moderate separation. Results confirm that the TNS program can successfully be used to simulate transonic viscous flows about complicated 3-D geometries.

Reznick, Steve↗

The Flight Telerobotic Servicer (FTS) - A focus for automation and robotics on the Space Station

The concept, fundamental design principles, and capabilities of the FTS, a multipurpose telerobotic system for use on the Space Station and Space Shuttle, are discussed. The FTS is intended to assist the crew in the performance of extravehicular tasks; the telerobot will also be used on the Orbital Maneuvering Vehicle to service free-flyer spacecraft. The FTS will be capable of both teleoperation and autonomous operation; eventually it may also utilize ground control. By careful selection of the functional architecture and a modular approach to the hardware and software design, the FTS can accept developments in artificial intelligence and newer, more advanced sensors, such as machine vision and collision avoidance.

Hinkal, Sanford W.↗

Modeling and optimization of a regenerative fuel cell system using the ASPEN process simulator

The Hydrogen-Oxygen Regenerative Fuel Cell System was identified as a key component for energy storage in support of future lunar missions. Since the H2-O2 regenerative electrochemical conversion technology has not yet been tested in space applications, it is necessary to implement predictive techniques to develop initial feasible system designs. The ASPEN simulation software furnishes a constructive medium for analyzing and for optimizing such systems. A rudimentary regenerative fuel cell system design was examined using the ASPEN simulator and this modular approach allows for easy addition of supplementary ancillary components and easy integration with life support systems. The modules included in the preliminary analyses may serve as the fundamental structure for more complicated energy storage systems.

Maloney, Thomas M.↗

The CELSS breadboard project: Plant production

NASA's Breadboard Project for the Controlled Ecological Life Support System (CELSS) program is described. The simplified schematic of a CELSS is given. A modular approach is taken to building the CELSS Breadboard. Each module is researched in order to develop a data set for each one prior to its integration into the complete system. The data being obtained from the Biomass Production Module or the Biomass Production Chamber is examined. The other primary modules, food processing and resource recovery or waste management, are discussed briefly. The crew habitat module is not discussed. The primary goal of the Breadboard Project is to scale-up research data to an integrated system capable of supporting one person in order to establish feasibility for the development and operation of a CELSS. Breadboard is NASA's first attempt at developing a large scale CELSS.

Knott, William M.↗

Modeling and optimization of a regenerative fuel cell system using the ASPEN process simulator

The Hydrogen-Oxygen Regenerative Fuel Cell System was identified as a key component for energy storage in support of future lunar missions. Since the H2-O2 regenerative electrochemical conversion technology has not yet been tested in space applications, it is necessary to implement predictive techniques to develop initial feasible system designs. The ASPEN simulation software furnishes a constructive medium for analyzing and optimizing such systems. A rudimentary regenerative fuel cell system design was examined using the ASPEN simulator and this modular approach allows for easy addition of supplementary ancillary components and easy integration with life support systems. The modules included in the preliminary analyses may serve as the fundamental structure for more complicated energy storage systems.

Maloney, Thomas M.↗

User's guide to the Reliability Estimation System Testbed (REST)

The Reliability Estimation System Testbed is an X-window based reliability modeling tool that was created to explore the use of the Reliability Modeling Language (RML). RML was defined to support several reliability analysis techniques including modularization, graphical representation, Failure Mode Effects Simulation (FMES), and parallel processing. These techniques are most useful in modeling large systems. Using modularization, an analyst can create reliability models for individual system components. The modules can be tested separately and then combined to compute the total system reliability. Because a one-to-one relationship can be established between system components and the reliability modules, a graphical user interface may be used to describe the system model. RML was designed to permit message passing between modules. This feature enables reliability modeling based on a run time simulation of the system wide effects of a component's failure modes. The use of failure modes effects simulation enhances the analyst's ability to correctly express system behavior when using the modularization approach to reliability modeling. To alleviate the computation bottleneck often found in large reliability models, REST was designed to take advantage of parallel processing on hypercube processors.

Nicol, David M.↗

Near-term SEI science missions utilizing an evolutionary lunar transportation system

An evolutionary program of space science missions for the lunar surface and the transportation system concept developed to deploy them are described. Lunar-based science systems will evolve from simple, robotic instruments such as a lunar transit telescope (LTT) to large, observatory-class instruments like a 16-meter optical telescope assembled by astronauts at a lunar base. A transportation system concept to support the Space Exploration Initiative (SEI) and the deployment of these science payloads is described. Beginning with a post-Artemis lander capability, a modular approach to lunar landers is proposed as a way to maximize commonality and to support evolving SEI transportation requirements.

Johnson, Charles L.↗

Integrated modular propulsion for launch vehicles

The paper proposes a modular approach to rocket propulsion which offers a versatile method for realizing the goals of low cost, safety, reliability, and ease of operation. It is shown that, using practical modules made up of only 4-6 individual elements, it is possible to achieve thrust levels of 2-3 mln lbf and more, using turbomachinery, thrust chambers, lines, and valves about the size of SSME hardware. The approach is illustrated by a LOX/LH2 configuration.

Knuth, William↗