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Results for “ELECTROMAGNETIC CONTROL”

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 127 records · Page 7
All sourcesNASA NTRSDOE OSTI
NASA NTRS1969

Quantum optics or quantum electronics.

Quantum optics or electronics, discussing electromagnetic waves control and interactions with matter, maser oscillators theory and characteristics, nonlinear optics, induced transparency, etc

Townes, C. H.↗
NASA NTRS1978

Planning for large construction projects in space

The paper discusses briefly some broad plans for developing the technology needed for large construction projects in space ranging from orbiting solar power stations to large communications antennas. Space construction classes include assembly of modules, deployment of compacted structures, assembly of passive preformed pieces, and fabrication of structures from sheet stock. Technological areas related to structural concepts include (1) analyses for prediction of structural behavior, structural/control interaction, electromagnetic and control performance, and integrated design development; (2) electronics for signal conditioning and data acquisition, power distribution, and signal channel interference and multipaction; (3) concepts for shape control, attitude/pointing control, and orbital transfer and station keeping; and (4) materials and techniques for 30-year dimensional stable composites, thermal control, thin-lightweight structural alloys, and material joining in space. The concept of a power module for the construction operations is discussed along with a concept for a habitability module.

Disher, J. H.↗
NASA NTRS1979

Deployable antenna technology development for the Large Space Systems Technology program

The critical technologies associated with the development of deployable reflector antenna technology for the LSST program will be derived from NASA mission models and the subsequent requirements will be related to the classes of missions involved. The approach formulated for the development of reflector technology is based on the development of specific reflector concepts that have been identified as leading candidates for future applications. The development approach will be augmented by supporting technology disciplines such as controls, materials, electromagnetic analysis, as well as the capability of analytically predicting the overall performance of the large space system.

Freeland, R. E.↗
NASA NTRS1983

Large Space Antenna Systems Technology, part 1

This publication is a compilation of the unclassified papers presented at the NASA Conference on Large Space Antenna Systems Technology, which was held at the Langley Research Center, Hampton, Virginia, November 30 - December 3, 1982. The conference, which was sponsored jointly by the NASA Office of Aeronautics and Space Technology (OAST) and the NASA Langley Research Center, was organized into five sessions: Systems, Structures Technology, Control Technology, electromagnetics, and Space Flight Test and Evaluation. All speakers and topics were selected by the session cochairmen and included representation from industry, universities, and government. The program was organized to provide a comprehensive review of space missions requiring large antenna systems and of the status of key technologies required to enable these missions.

Large space systems↗
NASA NTRS1983

Use of electromagnetic models in the optimal control of large space antennas

A general approach to the optimal control of large space antennas based on their RF/structural characteristics is described. The approach consists of defining a cost functional based on the degradation of the RF performance of the antenna and using the structural model as the dynamic system. The method is applied to the design of an optimal controller for a 55-m, wrap-rib offset-fed antenna. Simulation results show that control energy consumption is reduced to aproximately one third of the energy used to achieve the same RF performance with traditional control strategies.

Manshadi, F.↗
NASA NTRS1985

Large Space Antenna Systems Technology, 1984

Papers are presented which provide a comprehensive review of space missions requiring large antenna systems and of the status of key technologies required to enable these missions. Topic areas include mission applications for large space antenna systems, large space antenna structural systems, materials and structures technology, structural dynamics and control technology, electromagnetics technology, large space antenna systems and the space station, and flight test and evaluation.

Boyer, W. J.↗
NASA NTRS1985

Large Space Antenna Systems Technology, 1984

Mission applications for large space antenna systems; large space antenna structural systems; materials and structures technology; structural dynamics and control technology, electromagnetics technology, large space antenna systems and the Space Station; and flight test and evaluation were examined.

Boyer, W. J.↗
NASA NTRS1988

Digital avionics susceptibility to high energy radio frequency fields

Generally, noncritical avionic systems for transport category aircraft have been designed to meet radio frequency (RF) susceptibility requirements set forth in RTCA DO 160B, environmental conditions and test procedures for airborne equipment. Section 20 of this document controls the electromagnetic interference (EMI) hardening for avionics equipment to levels of 1 and 2 V/m. Currently, US equipment manufacturers are designing flight-critical fly-by-wire avionics to a much higher level. The US Federal Aviation Administration (FAA) has requested that the RTCA SC-135 high-energy radio frequency (HERF) working group develop appropriate testing procedures for section 20 of RTCA DO 160B for radiated and conducted susceptibility at the box and systems level. The FAA has also requested the SAE AE4R committee to address installed systems testing, airframe shielding effects and RF environment monitoring. Emitters of interest include radar (ground, ship, and aircraft) commercial broadcast and TV station, mobile communication, and other transmitters that could possibly affect commercial aircraft.

Larsen, William E.↗
NASA NTRS1989

Power transmission cable development for the Space Station Freedom electrical power system

Power transmission cable is presently being evaluated under a NASA Lewis Research Center advanced development contract for application in the Space Station Freedom (SSF) electrical power system (EPS). Evaluation testing has been performed by TRW and NASA Lewis Research Center. The results of this development contract are presented. The primary cable design goals are to provide (1) a low characteristic inductance to minimize line voltage drop at 20 kHz, (2) electromagnetic compatibility control of the 20-kHz ac power current, (3) a physical configuration that minimizes ac resistance and (4) release of trapped air for corona-free operation.

Schmitz, Gregory V.↗
NASA NTRS1996

A Hybrid Nonlinear Control Scheme for Active Magnetic Bearings

A nonlinear control scheme for active magnetic bearings is presented in this work. Magnet winding currents are chosen as control inputs for the electromechanical dynamics, which are linearized using feedback linearization. Then, the desired magnet currents are enforced by sliding mode control design of the electromagnetic dynamics. The overall control scheme is described by a multiple loop block diagram; the approach also falls in the class of nonlinear controls that are collectively known as the 'integrator backstepping' method. Control system hardware and new switching power electronics for implementing the controller are described. Various experiments and simulation results are presented to demonstrate the concepts' potentials.

Xia, F.↗
NASA NTRS2000

Fifth International Symposium on Magnetic Suspension Technology

In order to examine the state of technology of all areas of magnetic suspension and to review recent developments in sensors, controls, superconducting magnet technology, and design/implementation practices, the Fifth International Symposium on Magnetic Suspension Technology was held at the Radisson Hotel Santa Barbara, Santa Barbara, California, on December 1-3, 1999. The symposium included 18 sessions in which a total of 53 papers were presented. The technical sessions covered the areas of bearings, controls, modeling, electromagnetic launch, magnetic suspension in wind tunnels, applications flywheel energy storage, rotating machinery, vibration isolation, and maglev. A list of attendees is included in the document.

Groom, Nelson J.↗
NASA NTRS2002

Operation of a Thin-Film Inflatable Concentrator System Demonstrated in a Solar Thermal Vacuum Environment

Thin-film inflatable solar concentrators offer significant advantages in comparison to stateof- the-art rigid panel concentrators, including low weight, low stowage volume, and simple gas deployment. From June 10 to 22, 2001, the ElectroMagnetic Radiation Control Experiment (EMRCE) Team used simulated solar energy to demonstrate the operation of an inflatable concentrator system at NASA Glenn Research Center's Tank 6 thermal vacuum facility. The joint Government/industry test team was composed of engineers and technicians from Glenn, the Air Force Research Laboratory, SRS Technologies, and ATK Thiokol Propulsion. The research hardware consisted of the following: 1) A thin-film inflatable concentrator; 2) The hexapod pointing and focus control system; 3) Two rigidized support struts using two candidate technologies - ultraviolet-rigidized glass and radiation-cured isographite.

Wong, Wayne A.↗
DOE OSTI2020

Composite materials with self-regulated infrared emissivity and environment responsive fibers

A composite fabric having self-regulating Infrared emissivity includes meta fibers formed with optical nanostructures and an environment (temperature and/or moisture) responsive mechanism configured to adjust a relative disposition between the optical structures to control the electromagnetic coupling therebetween, thus regulating the infrared emissivity of the composite fabric to maintain a user of the fabric in a temperature/moisture comfort zone. The environment responsive mechanism may include a temperature responsive polymer layer on the fiber capable of expansion/shrinkage depending on the applied temperature, or a moisture responsive fiber changing its shape depending on the moisture level to affect spacing between the optical nanostructures.

Wang, Yuhuang↗