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At least 145 records · Page 8
All sourcesNASA NTRSDOE OSTI
NASA NTRS1973

Multifunction display system

The design and characteristics of a multifunction display system are discussed. The system is a general purpose, time-shared, electro-optical display driven by onboard data management systems. It is capable of presenting information in forms such as alphanumerics, symbolics, and graphics, separately or in combination. The components of the system are: (1) data terminal simulator/input loader, (2) keyboard controller, (3) CRT display indicator, and (4) programmable symbol generator.

Kendall, K.↗
NASA NTRS1976

Investigation of the use of an electronic multifunction display and an electromechanical horizontal situation indicator for guidance and control of powered-lift short-haul aircraft

The use which pilots make of a moving map display from en route through the terminal area and including the approach and go-around flight phases was investigated. The content and function of each of three primary STOLAND displays are reviewed from an operational point of view. The primary displays are the electronic attitude director indicator (EADI), the horizontal situation indicator (HSI), and the multifunction display (MFD). Manually controlled flight with both flight director guidance and raw situation data is examined in detail in a simulated flight experiment with emphasis on tracking reference flight plans and maintaining geographic orientation after missed approaches. Eye-point-of-regard and workload measurements, coupled with task performance measurements, pilot opinion ratings, and pilot comments are presented. The experimental program was designed to offer a systematic objective and subjective comparison of pilots' use of the moving map MFD in conjunction with the other displays.

Clement, W. F.↗
NASA NTRS1982

Geostationary operational environmental satellite /GOES/ - A multifunctional satellite

The GOES satellites are multifunctional satellites whose primary function is to provide continuous measurements of the earth's surface and atmosphere from two geostationary orbit locations: 75 deg W and 135 deg W. This objective is accomplished with the visible infrared spin scan radiometer Atmospheric Sounder (VAS), and the Space Environment Monitor (SEM), which includes three instruments: a magnetometer, solar X-ray sensor, and an energetic particle sensor, which monitor the near earth space environment. The satellite's communication system provides several user oriented functions, including: (1) Transmission of VAS data; (2) Transmission of SEM data; (3) Transponder capabilities for stretched VAS (SVAS) data, weather facsimile (WEFAX) data, and trilateration signals; (4) transponder capabilities for data collection platform interrogation and data collection platform reply.

Mallette, L. A.↗
NASA NTRS1983

Spaceborne multifunction imaging radar antenna development

Past and present studies of Multifunction Synthetic Aperture Radar Technology at NASA's Johnson Space Center have given attention to the design of lens antennas, planar arrays, and continuous apertures, such as reflectors. Current emphasis is on an interleaved, open ended waveguide array and microstrip antenna, with design work proceeding for multifrequency operation L, C, and X-band antennas, all of which possess multipolarization. In order to meet ground swath and azimuth resolution requirements, the antennas are designed to provide a beamwidth of 6.2 deg in elevation and 1 deg in azimuth.

Schaeper, H. R. A.↗
NASA NTRS1986

Test and evaluation of a multifunction keyboard and a dedicated keyboard for control of a flight management computer

A flight management computer (FMC) control display unit (CDU) test was conducted to compare two types of input devices: a fixed legend (dedicated) keyboard and a programmable legend (multifunction) keyboard. The task used for comparison was operation of the flight management computer for the Boeing 737-300. The same tasks were performed by twelve pilots on the FMC control display unit configured with a programmable legend keyboard and with the currently used B737-300 dedicated keyboard. Flight simulator work activity levels and input task complexity were varied during each pilot session. Half of the points tested were previously familiar with the B737-300 dedicated keyboard CDU and half had no prior experience with it. The data collected included simulator flight parameters, keystroke time and sequences, and pilot questionnaire responses. A timeline analysis was also used for evaluation of the two keyboard concepts.

Crane, J. M.↗
NASA NTRS1991

The Rocketdyne Multifunction Tester. Part 1: Test Method

The Rocketdyne Multifunction Tester is a general purpose test apparatus which utilizes axial and radial magnetic bearings as shaft excitation devices. The tester is modular in design so that different seal and bearing packages can be tested on the same test stand. The tester will be used for rotordynamic coefficient extraction, as well as life and fluid/material compatibility evaluations. Use of a magnetic bearing as a shaft excitation device opens up many possibilities for shaft excitation and rotordynamic coefficient extraction. In addition to describing the basic apparatus, some of the excitation and extraction methods are described. Some of the excitation methods to be discussed include random, aperiodic, harmonic, impulse and chirp.

Murphy, Brian T.↗
NASA NTRS1991

The Rocketdyne Multifunction Tester. Part 2: Operation of a Radial Magnetic Bearing as an Excitation Source

The operation of the magnetic bearing used as an excitation source in the Rocketdyne Multifunction Tester is described. The tester is scheduled for operation during the summer of 1990. The magnetic bearing can be used in two control modes: (1) open loop mode, in which the magnetic bearing operates as a force actuator; and (2) closed loop mode, in which the magnetic bearing provides shaft support. Either control mode can be used to excite the shaft; however, response of the shaft in the two control modes is different due to the alteration of the eigenvalues by closed loop mode operation. A rotordynamic model is developed to predict the frequency response of the tester due to excitation in either control mode. Closed loop mode excitation is shown to be similar to the excitation produced by a rotating eccentricity in a conventional bearing. Predicted frequency response of the tester in the two control modes is compared, and the maximum response is shown to be the same for the two control modes when synchronous unbalance loading is not considered. The analysis shows that the response of this tester is adequate for the extraction of rotordynamic stiffness, damping, and inertia coefficients over a wide range of test article stiffnesses.

Hawkins, L. A.↗
NASA NTRS1996

Large Format Multifunction 2-Terabyte Optical Disk Storage System

The Kodak Digital Science OD System 2000E automated disk library (ADL) base module and write-once drive are being developed as the next generation commercial product to the currently available System 2000 ADL. Under government sponsorship with the Air Force's Rome Laboratory, Kodak is developing magneto-optic (M-O) subsystems compatible with the Kodak Digital Science ODW25 drive architecture, which will result in a multifunction (MF) drive capable of reading and writing 25 gigabyte (GB) WORM media and 15 GB erasable media. In an OD system 2000 E ADL configuration with 4 MF drives and 100 total disks with a 50% ration of WORM and M-O media, 2.0 terabytes (TB) of versatile near line mass storage is available.

Kaiser, David R.↗
NASA NTRS2001

On Multifunctional Collaborative Methods in Engineering Science

Multifunctional methodologies and analysis procedures are formulated for interfacing diverse subdomain idealizations including multi-fidelity modeling methods and multi-discipline analysis methods. These methods, based on the method of weighted residuals, ensure accurate compatibility of primary and secondary variables across the subdomain interfaces. Methods are developed using diverse mathematical modeling (i.e., finite difference and finite element methods) and multi-fidelity modeling among the subdomains. Several benchmark scalar-field and vector-field problems in engineering science are presented with extensions to multidisciplinary problems. Results for all problems presented are in overall good agreement with the exact analytical solution or the reference numerical solution. Based on the results, the integrated modeling approach using the finite element method for multi-fidelity discretization among the subdomains is identified as most robust. The multiple method approach is advantageous when interfacing diverse disciplines in which each of the method's strengths are utilized.

Ransom, Jonathan B.↗
NASA NTRS2002

Microwave-Driven Multifunctional Capability of Membrane Structures

A large, ultra lightweight space structure, such as solar sails and Gossamer spacecrafts, requires a distributed power source to alleviate wire networks, unlike the localized on-board power infrastructures typically found in most small spacecrafts. The concept of microwave-driven multifunctional capability for membrane structures is envisioned as the best option to alleviate the complexity associated with hard-wired control circuitry and on-board power infrastructures. A rectenna array based on a patch configuration for high voltage output was developed to drive membrane actuators, sensors, probes, or other devices. Networked patch rectenna array receives and converts microwave power into a DC power for an array of smart actuators. To use microwave power effectively, the concept of a power allocation and distribution (PAD) circuit is adopted for networking a rectenna/actuator patch array. The use of patch rectennas adds a significant amount of rigidity to membrane flexibility and they are relatively heavy. A dipole rectenna array (DRA) appears to be ideal for thin-film membrane structures, since DRA is flexible and light. Preliminary design and fabrication of PAD circuitry that consists of a few nodal elements were made for laboratory testing. The networked actuators were tested to correlate the network coupling effect, power allocation and distribution, and response time.

Choi, Sang H.↗
NASA NTRS2003

Color and Luminance Analysis of the Space Shuttle Multifunction Display Units(MDUs)

The purpose of this evaluation is to measure and analyze the colors that can be shown on the Multifunction Display Units (MDUs) of the Space Shuttle cockpit. The evaluation was conducted in the JSC Avionics Engineering Laboratory (JAEL) in building 16A at NASA Johnson Space Center. The JAEL contains a suite of 11 MDUs, each of which can be configured to show colors based on input values of the MDU red, green and blue (RGB) channels. Each of the channels has a range of 0 to 15. For example, bright green is produced by setting RGB to 0,15,0, and orange is produced by setting RGB to 15,4,0. The Cockpit Avionics Upgrade (CAU) program has specified the RGB settings for 14 different colors in the Display Design document (Rev A, 29 June 2001). The analysis in this report may help the CAU program determine better RGB settings for the colors.

McCandless, Jeffrey W.↗
NASA NTRS2004

E-beam-Cure Fabrication of Polymer Fiber/Matrix Composites for Multifunctional Radiation Shielding

Aliphatic polymers were identified as optimum radiation polymeric shielding materials for building multifunctional structural elements. Conceptual damage-tolerant configurations of polyolefins have been proposed but many issues on the manufacture remain. In the present paper, we will investigate fabrication technologies with e-beam curing for inclusion of high-strength aliphatic polymer fibers into a highly cross-linked polyolefin matrix. A second stage of development is the fabrication methods for applying face sheets to aliphatic polymer closed-cell foams.

Wilson, John W.↗
NASA NTRS2003

Multifunction Sensor Algorithm Development

A multifunction sensor has been developed in the Sensors and Electronics Technology Branch. It is capable of measuring heat flux, surface temperature, and, in principle, strain magnitude & direction, while compensating for the apparent strain due to changes in operating temperature. In order to achieve this strain measuring capability, Mr. Zeller will work on improving the signal processing algorithm to include several special cases, such as when the principal strain axis lies either parallel to or perpendicular to one of the arms of the sensor. In addition, he will implement a GUI to make the sensor more user friendly.

Zeller, Donald F.↗
NASA NTRS2005

Multi-Scale Sizing of Lightweight Multifunctional Spacecraft Structural Components

This document is the final report for the project entitled, "Multi-Scale Sizing of Lightweight Multifunctional Spacecraft Structural Components," funded under the NRA entitled "Cross-Enterprise Technology Development Program" issued by the NASA Office of Space Science in 2000. The project was funded in 2001, and spanned a four year period from March, 2001 to February, 2005. Through enhancements to and synthesis of unique, state of the art structural mechanics and micromechanics analysis software, a new multi-scale tool has been developed that enables design, analysis, and sizing of advance lightweight composite and smart materials and structures from the full vehicle, to the stiffened structure, to the micro (fiber and matrix) scales. The new software tool has broad, cross-cutting value to current and future NASA missions that will rely on advanced composite and smart materials and structures.

Bednarcyk, Brett A.↗
NASA NTRS2004

Multifunctional Inflatable Structure Being Developed for the PowerSphere Concept

NASA has funded a collaborative team of The Aerospace Corporation, ILC Dover, Lockheed Martin, and NASA Glenn Research Center to develop the Multifunctional Inflatable Structure (MIS) for a "PowerSphere" concept through a NASA Research Announcement. This power system concept has several advantages, including a high collection area, low weight and stowage volume, and the elimination of all solar array pointing mechanisms. The current 3-year effort will culminate with the fabrication and testing of a fully functional engineering development unit. The baseline design of the Power-Sphere consists of two opposing semispherical domes connected to a central spacecraft. Each semispherical dome consists of hexagonal and pentagonal solar cell panels that together form a geodetic sphere. Inflatable ultraviolet (UV) rigidizable tubular hinges between the solar cell panels and UV rigidizable isogrid center columns with imbedded flex circuitry form the MIS. The reference configuration for the PowerSphere is a 0.6-m-diameter (fully deployed) spacecraft with a total mass budget of 4 kg (1 kg for PowerSphere, 3 kg for spacecraft) capable of producing 29 W of electricity with 10-percent-efficient thin-film solar cells. In a stowed configuration, the solar cell panels will be folded sequentially to the outside of the instrument decks. The center column will be z-folded between the instrument decks and the spacecraft housing for packaging. The instrument panel will secure the z-folded stack with launch ties. After launch, once the release tie is triggered, the center column and hinge tubes will inflate and be rigidized in their final configurations by ultraviolet radiation. The overall PowerSphere deployment sequence is shown pictorially in the following illustration.

Peterson, Todd T.↗
NASA NTRS2005

E-Beam Processing of Polymer Matrix Composites for Multifunctional Radiation Shielding

Aliphatic polymers were identified as optimum radiation shielding polymeric materials for building multifunctional structural elements for in-space habitats. Conceptual damage tolerant configurations of polyolefins have been proposed, but many manufacturing issues relied on methods and materials which have sub-optimal radiation shielding characteristics (for example, epoxy matrix and adhesives). In the present approach, we shall investigate e-beam processing technologies for inclusion of high-strength aliphatic polymer reinforcement structures into a highly cross-linked polyolefin matrix. This paper reports the baseline thermo-mechanical properties of low density polyethylene and highly crystallized polyethylene.

Hou, Tan-Hung↗
NASA NTRS2006

Towards Multifunctional Characteristics of Embedded Structures With Carbon Nanotube Yarns

This paper presents recent results on research of achieving multifunctional structures utilizing Carbon Nanotube (CNT) yarns. The investigation centers on creating composite structures with CNT yarns to simultaneously achieve increases in mechanical strength and the ability to sense strain. The CNT yarns used in our experiments are of the single-ply and two-ply variety with the single-ply yarns having diameters on the order of 10-20 m. The yarns are embedded in silicon rubber and polyurethane test specimens. Mechanical tests show an increase in modulus of elasticity, with an additional weight increase of far less than one-percent. Sensing characteristics of the yarns are investigated on stainless steel test beams in an electrical bridge configuration, and are observed to have a strain sensitivity of 0.7mV/V/1000 micro-strain. Also reported are measurements of the average strain distribution along the direction of the CNT yarns on square silicon rubber membranes.

Hernandez, Corey D.↗