295
295
May 6, 2010
05/10
by
Elkind, J. I.; Green, D. M.; Kelly, J. A.; Young, L. R
texts
eye 295
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Adaptive characteristics of manual tracking
Topics: DYNAMIC CONTROL, MANUAL CONTROL, TRACKING (POSITION), DYNAMIC CONTROL, MANUAL CONTROL, TRACKING
299
299
May 31, 2011
05/11
by
Li, Jian-Zhong; Cheung, Samson H.; Ning, C. Z
texts
eye 299
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Carrier diffusion and thermal conduction play a fundamental role in the operation of high-power, broad-area semiconductor lasers. Restricted geometry, high pumping level and dynamic instability lead to inhomogeneous spatial distribution of plasma density, temperature, as well as light field, due to strong light-matter interaction. Thus, modeling and simulation of such optoelectronic devices rely on detailed descriptions of carrier dynamics and energy transport in the system. A self-consistent...
Topics: CONTROLLABILITY, DYNAMIC CONTROL, ALGORITHMS, POLYNOMIALS
Topics: manualsonline, manuals, dynamat_dynamic_control
Topics: manualsonline, manuals, dynamat_dynamic_control
Topics: manualsonline, manuals, dynamat_dynamic_control
A new control method was proposed in the current paper for controlling hybrid system consisting of fuel cell and battery. In the proposed control system, a method through which active power of fuel cell is supplied with a relatively high time constant was chosen contributing to enhancement of fuel cell life and maintenance of its terminal in the range of the nominal voltage. Furthermore, ensemble of fuel cell and inverter were used to supply instantaneous reactive power as well; which is...
Topics: Dynamic Model, Dynamic Control, Hybrid System, Fuel Cell, Battery
711
711
Jun 21, 2010
06/10
by
Chu, W.-H
texts
eye 711
favorite 0
comment 0
Theory for low gravity fuel sloshing in arbitrary axisymmetric rigid tank
Topics: AUTOMATA THEORY, DYNAMIC CONTROL, SERVOMECHANISMS, ADAPTIVE CONTROL, NUMERICAL CONTROL
236
236
Jun 11, 2011
06/11
by
Colaprete, A.; Haberle, R. M.; Segura, T. L.; Toon, O. B.; Zahnle, K
texts
eye 236
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The first images returned by the Mariner 7 spacecraft of the Martian surface showed a landscape heavily scared by impacts. Mariner 9 imaging revealed geomorphic features including valley networks and outflow channels that suggest liquid water once flowed at the surface of Mars. Further evidence for water erosion and surface modification has come from the Viking Spacecraft, Mars Pathfinder, Mars Global Surveyor's (MGS) Mars Orbiter Camera (MOC), and Mars Odyssey's THEMIS instrument. In addition...
Topics: AUTONOMY, SENSITIVITY ANALYSIS, GAIT, ROBOTS, GENETIC ALGORITHMS, DYNAMIC CONTROL, WALKING,...
285
285
Sep 20, 2010
09/10
by
Brinker, David J.; Flood, Dennis J
texts
eye 285
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comment 0
The development of an advanced photovoltaic power system that would have application for a manned lunar base is currently planned under the Surface Power element of Pathfinder. Significant mass savings over state-of-the-art photovoltaic/battery systems are possible with the use of advanced lightweight solar arrays coupled with regenerative fuel cell storage. The solar blanket, using either ultrathin GaAs or amorphous silicon solar cells, would be integrated with a reduced-g structure....
Topics: CONTROLLERS, DYNAMIC CONTROL, FLEXIBLE BODIES, STRUCTURAL DESIGN, DYNAMIC RESPONSE, FEEDBACK...
281
281
Jul 11, 2010
07/10
by
DELIMARSKIY, Y. K
texts
eye 281
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RESULTS ARE REVIEWED WHICH WERE OBTAINED IN THE POLAROGRAPHY OF MOLTEN SALTS UTILIZING TERNARY ELECTROLYTES RATHER THAN THE LIQUID CAPILLARY ELECTRODES USED BY STEINBERG AND NACHTREIB, AND SHOWING MATHEMATICAL MODELS CONSISTENLY PREDICTING OUTCOMES WHICH CAN BE PROVEN EMPIRICALLY.
Topics: AIRCRAFT STABILITY, DYNAMIC CONTROL, MARKOV PROCESSES, CIRCULAR ORBITS, DIFFERENTIAL EQUATIONS,...
200
200
May 22, 2011
05/11
by
Jong, Jen-Y
texts
eye 200
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This study will provide timely assessment of SSME component operational status, identify probable causes of malfunction, and indicate feasible engineering solutions. The final result of this program will yield an advanced nonlinear signal analysis topographical mapping system (ATMS) of nonlinear and nonstationary spectral analysis software package integrated with the Compressed SSME TOPO Data Base (CSTDB) on the same platform. This system will allow NASA engineers to retrieve any unique defect...
Topics: AUTONOMOUS NAVIGATION, DYNAMIC CONTROL, ROBOT CONTROL, ROBOTICS, AUTONOMY, DOMAINS, SURFACE...
476
476
Jun 9, 2011
06/11
by
Salas, A. O.; Townsend, J. C
texts
eye 476
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Frameworks or problem solving environments that support application development form an active area of research. The Multidisciplinary Optimization Branch at NASA Langley Research Center is investigating frameworks for supporting multidisciplinary analysis and optimization research. The Branch has generated a list of framework requirements, based on the experience gained from the Framework for Interdisciplinary Design Optimization project and the information acquired during a framework...
Topics: NEURAL NETS, DYNAMIC CONTROL, DESIGN ANALYSIS, REACTION WHEELS, SIMULATION, FEEDFORWARD CONTROL,...
290
290
Jul 11, 2010
07/10
by
Aoyagi, K.; Falarski, M. D.; Koenig, D. G
texts
eye 290
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Investigations were conducted in the Ames 40- by 80-Foot Wind Tunnel to determine the aerodynamic characteristics of a large-scale subsonic jet transport model with an upper surface blown flap system. The model had a 25 deg swept wing of aspect ratio 7.28 and four turbofan engines. The lift of the flap system was augmented by turning the turbofan exhaust over the Coanda surface. Results were obtained for several flap deflections with several wing leading-edge configurations at jet momentum...
Topics: AUTOMATIC PILOTS, DIGITAL SIMULATION, V/STOL AIRCRAFT, DEGREES OF FREEDOM, DYNAMIC CONTROL, FLIGHT...
360
360
Jun 11, 2011
06/11
by
Hambourger, Paul D.; Kerslake, Thomas W.; Waters, Deborah L
texts
eye 360
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Multi-kilogram class microsatellites with a PowerSphere electric power system are attractive for fulfilling a variety of potential NASA missions. However, PowerSphere polymer surfaces must be coated with a film that has suitable electrical sheet resistivity for electrostatic discharge control, be resistant to atomic oxygen attack, be transparent to ultraviolet light for composite structure curing and resist ultraviolet light induced darkening for efficient photovoltaic cell operation. In...
Topics: AEROSPACE ENGINEERING, ATTITUDE CONTROL, DYNAMIC CONTROL, SPACECRAFT CONTROL, X RAY IMAGERY, ESA...
Certain planning systems that deal with quantitative time constraints have used an underlying Simple Temporal Problem solver to ensure temporal consistency of plans. However, many applications involve processes of uncertain duration whose timing cannot be controlled by the execution agent. These cases require more complex notions of temporal feasibility. In previous work, various "controllability" properties such as Weak, Strong, and Dynamic Controllability have been defined. The most...
Topics: NASA Technical Reports Server (NTRS), CONTROLLABILITY, DYNAMIC CONTROL, ALGORITHMS, POLYNOMIALS,...
261
261
Jun 21, 2010
06/10
by
Benson, H. E
texts
eye 261
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comment 0
No Abstract Available
Topics: CONTROL SIMULATION, DYNAMIC CONTROL, MODAL RESPONSE, SATURN S-4B STAGE, BURNING TIME, MATRICES...
377
377
Aug 1, 2010
08/10
by
Wolf, David A.; Schwarz, Ray P
texts
eye 377
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The gravity induced motions, through the culture media, is calculated of living tissue segments cultured in the NASA rotating zero head space culture vessels. This is then compared with the media perfusion speed which is independent of gravity. The results may be interpreted as a change in the physical environment which will occur by operating the NASA tissue culture systems in actual microgravity (versus unit gravity). The equations governing particle motions which induce flows at the surface...
Topics: ACTUATORS, ROBOTICS, TRAJECTORIES, END EFFECTORS, MANIPULATORS, TRAJECTORY CONTROL, TRAJECTORY...
396
396
Jun 9, 2011
06/11
by
Voland, R. T.; Rock, K. E.; Huebner, L. D.; Witte, D. W.; Fischer, K. E.; McClinton, C. R
texts
eye 396
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The Hyper-X Program, NASA's focused hypersonic technology program jointly run by NASA Langley and Dryden, is designed to move hypersonic, air-breathing vehicle technology from the laboratory environment to the flight environment, the last stage preceding prototype development. The Hyper-X research vehicle will provide the first ever opportunity to obtain data on an airframe integrated supersonic combustion ramjet propulsion system in flight, providing the first flight validation of wind tunnel,...
Topics: AERODYNAMIC CHARACTERISTICS, CONTROL SIMULATION, CONTROL SURFACES, DYNAMIC CONTROL, CONTROL...
Modern authorization systems span domains of administration, rely on many different authentication sources, and manage complex attributes as part of the authorization process. This . paper presents Cardea, a distributed system that facilitates dynamic access control, as a valuable piece of an inter-operable authorization framework. First, the authorization model employed in Cardea and its functionality goals are examined. Next, critical features of the system architecture and its handling of...
Topics: NASA Technical Reports Server (NTRS), ACCESS CONTROL, DYNAMIC CONTROL, COMPUTER INFORMATION...
271
271
Sep 20, 2010
09/10
by
NON
texts
eye 271
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A method for determining the angle of impact of an object on a thin-walled structure which determines the angle of impact through analysis of the acoustic waves which result when an object impacts a structure is presented. Transducers are placed on and in the surface of the structure which sense the wave caused in the structure by impact. The waves are recorded and saved for analysis. For source motion normal to the surface, the antisymmetric mode has a large amplitude while that of the...
Topics: CONTROL SYSTEMS DESIGN, DYNAMIC CONTROL, MANIPULATORS, ROBOT ARMS, ROBOT CONTROL, ROBOT DYNAMICS,...
233
233
May 6, 2010
05/10
by
Hetrick, D. L.; Melsa, J. L.; Murray, H. S.; Rosztoczy, Z.; Schultz, D. G.; Weaver, L. E
texts
eye 233
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Application of liapunov method and pontryagin principle to stability and optimization problems of nuclear reactors
Topics: AUTOMATIC CONTROL, PONTRYAGIN PRINCIPLE, REACTOR, CONTROL THEORY, DYNAMIC CONTROL, LIAPUNOV...
The completion of, and improvements made to, the software developed during 1990 for program maintenance on the PC and HEURIKON and transfer to the CYRO, and integration of the Rocketdyne vision software with the CYRO is documented. The new programs were used successfully by NASA, Rocketdyne, and UAH technicians and engineers to create, modify, upload, download, and control CYRO NC programs.
Topics: NASA Technical Reports Server (NTRS), DYNAMIC CONTROL, HARDWARE, ROBOT CONTROL, SOFTWARE...
295
295
Sep 20, 2010
09/10
by
Stark, Micheal E.; Booth, Eric W
texts
eye 295
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The current state of the art in software reuse is to provide problem domain components and problem domain objects. It is shown that designing verbatim resuable components at the architecture level can create approximately the same savings as the current state of the art. The new approach that needs to be applied to future systems is to strictly separate the problem domain objects from the particular systems architecture and to build the problem domain layers from bottom-up. When this approach...
Topics: ELECTROMAGNETS, MAGNETIC SUSPENSION, SISO (CONTROL SYSTEMS), DEGREES OF FREEDOM, DYNAMIC CONTROL,...
A series of ten task levels of increasing difficulty was compiled for use in comparative performance evaluations of available and future robotics technology. Each level has a breakdown of ten additional levels of difficulty to provide a layering of 100 levels. It is assumed that each level of task performance must be achieved by the system before it can be appropriately considered for the next level.
Topics: NASA Technical Reports Server (NTRS), ROBOTICS, TASK COMPLEXITY, TASKS, ASSEMBLY, DYNAMIC CONTROL,...
327
327
Aug 2, 2010
08/10
by
Mcgarry, Frank; Pajerski, Ros
texts
eye 327
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For 15 years, the Software Engineering Laboratory (SEL) at GSFC has been carrying out studies and experiments for the purpose of understanding, assessing, and improving software, and software processes within a production software environment. The SEL comprises three major organizations: (1) the GSFC Flight Dynamics Division; (2) the University of Maryland Computer Science Department; and (3) the Computer Sciences Corporation Flight Dynamics Technology Group. These organizations have jointly...
Topics: AIRCRAFT CONTROL, AIRCRAFT MODELS, CONTROL SYSTEMS DESIGN, DYNAMIC CONTROL, MACHINE LEARNING,...
348
348
May 28, 2011
05/11
by
Swartz, Marvin; Payne, Leslie J.; Plummer, Thomas B.; Thomas, Roger J.; White, Larry A.; Brosius, Jeffrey W.; Thompson, William T; Condor, Charles E.; Davila, Joseph M.; Haas, J. Patrick; Jordan, Stuart D.; Linard, David L.; Miko, Joseph J.; Nash, I. Carol; Novello, Joseph
texts
eye 348
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This paper describes mainly the 1997 version of the Solar EUV Rocket Telescope and Spectrograph (SERTS-97), a scientific experiment that operated on NASA's suborbital rocket flight 36.167-GS. Its function was to study activity on the Sun and to provide a cross calibration for the CDS instrument on the SOHO satellite. The experiment was designed, built, and tested by the Solar Physics Branch of the Laboratory for Astronomy and Solar Physics at the Goddard Space Flight Center (GSFC). Other...
Topics: NEUROMUSCULAR TRANSMISSION, PSYCHOMOTOR PERFORMANCE, MUSCULOSKELETAL SYSTEM, FINITE ELEMENT METHOD,...
261
261
May 29, 2011
05/11
by
Quattrochi, Dale A.; Emerson, Charles W.; Lam, Nina Siu-Ngam; Qiu, Hong-li
texts
eye 261
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Scale is an ''innate'' concept in geographic information systems. It is recognized as something that is intrinsic to the capture, storage, manipulation, analysis, modeling, and output of space and time data within a GIS purview, yet the relative meaning and ramifications of scaling spatial and temporal data from this perspective remain enigmatic. As GISs become more sophisticated as a product of more robust software and more powerful computer systems, there is an urgent need to examine the...
Topics: ROBUSTNESS (MATHEMATICS), COMPONENT RELIABILITY, STRUCTURAL ANALYSIS, ALGORITHMS, TWO DIMENSIONAL...
184
184
Jun 9, 2011
06/11
by
Gnoffo, Peter A.; Inger, George R
texts
eye 184
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The local viscous-inviscid interaction field generated by a wall temperature jump on a flat plate in supersonic flow and on the windside of a Reusable Launch Vehicle in hypersonic flow is studied in detail by both a Navier-Stokes numerical code and an analytical triple-deck model. Treatment of the rapid heat transfer changes both upstream and downstream of the jump is included. Closed form relationships derived from the triple-deck theory are presented. The analytically predicted pressure and...
Topics: DYNAMIC CONTROL, SUPERSONIC AIRCRAFT, ELASTIC PROPERTIES, FLIGHT CONTROL, HIGHLY MANEUVERABLE...
189
189
May 31, 2011
05/11
by
Cabell, Randolph H.; Kegerise, Michael A.; Cox, David E.; Gibbs, Gary P
texts
eye 189
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An experimental study of the application of discrete-time, linear quadratic control design methods to the cavity tone problem is described. State space models of the dynamics from a synthetic jet actuator at the leading edge of the cavity to two pressure sensors in the cavity were computed from experimental data. Variations in model order, control order, control bandwidth, and properties of a Kalman state estimator were studied. Feedback control reduced the levels of multiple cavity tones at...
Topics: AEROELASTICITY, AERODYNAMIC BALANCE, AUTOMATIC CONTROL, SIMULATION, FLIGHT CONTROL, PILOTLESS...
268
268
Jun 2, 2011
06/11
by
Cosgriff, Laura M.; Lerch, Bradley A.; Hebsur, Mohan G.; Baaklini, George Y.; Ghosn, Louis J
texts
eye 268
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Enhanced, lightweight material systems, such as 17-4PH stainless steel sandwich panels are being developed for use as fan blades and fan containment material systems for next generation engines. In order to improve the production for these systems, nondestructive evaluation (NDE) techniques, such as ultrasonic spectroscopy, are being utilized to evaluate the brazing quality between the 17-4PH stainless steel face plates and the 17-4PH stainless steel foam core. Based on NDE data, shear tests...
Topics: DEPLOYMENT, RANDOM NOISE, NONLINEARITY, SYSTEMS ENGINEERING, TETHERED SATELLITES, SPACE MISSIONS,...
This report documents the first stage of research into Control Law - Control Allocation Interactions. A three-year research effort was originally proposed: 1. Create a desktop flight simulation environment under which experiments related to the open questions may be conducted. 2. Conduct research to determine which aspects of control allocation have impact upon control law design that merits further research. 3. Conduct research into those aspects of control allocation identified above, and...
Topics: NASA Technical Reports Server (NTRS), COMPUTERIZED SIMULATION, DYNAMIC CONTROL, FLIGHT SIMULATION,...
1,756
1.8K
Jun 21, 2010
06/10
by
Biderman, V. L., et al
texts
eye 1,756
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Construction and performance of automobile tires
Topics: HUMAN PERFORMANCE, OPTIMAL CONTROL, TASKS, LEARNING THEORY, MANUAL CONTROL, STOCHASTIC PROCESSES,...
The achievement of flight with manned, powered, heavier-than-air aircraft in 1903 marked the beginning of a new era in the means of transportation. A special advantage for aircraft was in speed. However, when an aircraft penetrates the air at very high speeds, the disturbed air is compressed and there are changes in the density, pressure and temperature of the air. These compressibility effects change the aerodynamic characteristics of an aircraft and introduce problems in drag, stability and...
Topics: NASA Technical Reports Server (NTRS), AERODYNAMIC CHARACTERISTICS, COMPRESSIBILITY EFFECTS, DYNAMIC...
Many complex real-world decision and control problems contain an underlying constraint reasoning problem. This is particularly evident in a recently developed approach to planning, where almost all planning decisions are represented by constrained variables. This translates a significant part of the planning problem into a constraint network whose consistency determines the validity of the plan candidate. Since higher-level choices about control actions can add or remove variables and...
Topics: NASA Technical Reports Server (NTRS), DYNAMIC CONTROL, CONTROL THEORY, MATHEMATICAL PROGRAMMING,...
The research addressed includes: (1) CSI issues in space robotics; (2) control of elastic payloads, which includes 1-DOF example, and 3-DOF harmonic drive arm with elastic beam; and (3) control of large space arms with elastic links, which includes testbed description, modeling, and experimental implementation of colocated PD and end-point tip position controllers.
Topics: NASA Technical Reports Server (NTRS), CONTROLLERS, DYNAMIC CONTROL, FLEXIBLE BODIES, LARGE SPACE...
Designing software is a complex process. How object-oriented design (OOD), coupled with formalized documentation and tailored object diagraming techniques, can reduce the complexity of the software design process is described and illustrated. The described OOD methodology uses a hierarchical decomposition approach in which parent objects are decomposed into layers of lower level child objects. A method of tracking the assignment of requirements to design components is also included. Increases...
Topics: NASA Technical Reports Server (NTRS), COMPUTER PROGRAMS, CONTROL SYSTEMS DESIGN, DYNAMIC CONTROL,...
203
203
Jun 21, 2010
06/10
by
Allen, W. H.; Haines, R. F
texts
eye 203
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comment 0
Irradiation phenomenon related to manual navigation
Topics: FEEDBACK CONTROL, SYSTEMS ENGINEERING, MATHEMATICAL MODELS, OPTIMAL CONTROL, SYSTEMS ANALYSIS,...
480
480
May 22, 2011
05/11
by
Bell, J. Brett; Nelms, R. M.; Shepherd, Michael T
texts
eye 480
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comment 0
The Component Development Division of the Propulsion Laboratory at Marshall Space Flight Center (MSFC) is currently investigating the use of electromechanical actuators for use in space transportation applications such as Thrust Vector Control (TVC). These high power servomechanisms will require rugged, reliable, and compact power electronic modules capable of modulating several hundred amperes of current at up to 270 Vdc. This paper will discuss the design and implementation of a...
Topics: CONTROL SYSTEMS DESIGN, ROBOTICS, DYNAMIC CONTROL, FEEDBACK CONTROL, REAL TIME OPERATION, ROBOT...
The environment framing the modem authorization process span domains of administration, relies on many different authentication sources, and manages complex attributes as part of the authorization process. Cardea facilitates dynamic access control within this environment as a central function of an inter-operable authorization framework. The system departs from the traditional authorization model by separating the authentication and authorization processes, distributing the responsibility for...
Topics: NASA Technical Reports Server (NTRS), ARCHITECTURE (COMPUTERS), COMPUTER INFORMATION SECURITY,...
Two major tests of the Tethered Satellite System (TSS) engineering and flight units were conducted to demonstrate the functionality of the hardware and software. Deficiencies in the hardware/software integration tests (HSIT) led to a recommendation for more testing to be performed. Selected problem areas of tether dynamics were analyzed, including verification of the severity of skip rope oscillations, verification or comparison runs to explore dynamic phenomena observed in other simulations,...
Topics: NASA Technical Reports Server (NTRS), COMPUTER PROGRAMS, DYNAMIC CONTROL, OSCILLATIONS, SYSTEMS...
The objective of the Space Engineering Research Center is to develop and disseminate a unified technology of controlled structures, to codify and disseminate this technology, and to train a generation of skilled engineers. The disciplinary research with the Controlled Structures Testbed (CST) is ongoing. The interferometer testbed became operational and is an active vehicle for researchers. The engineering model of the Mid-Deck Active Control Experiment (MACE) multibody test article also was...
Topics: NASA Technical Reports Server (NTRS), ACTIVE CONTROL, DYNAMIC CONTROL, DYNAMIC RESPONSE, FLEXIBLE...
622
622
Jul 26, 2010
07/10
by
Hughes, M. S.; Handley, S. M.; Miller, J. G.; Madaras, E. I
texts
eye 622
favorite 0
comment 0
No Abstract Available
Topics: CONFERENCES, CONTROL SYSTEMS DESIGN, DYNAMIC CONTROL, ROBOT DYNAMICS, ROBOTS, MAN MACHINE SYSTEMS,...
676
676
May 31, 2011
05/11
by
Butler, Dan; Ku, Jentung; Swanson, Theodor
texts
eye 676
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comment 0
Capillary pumped loops (CPLS) and loop heat pipes (LHPS) are versatile two-phase heat transfer devices which have recently gained increasing acceptance in space applications. Both systems work based on the same principles and have very similar designs. Nevertheless, some differences exist in the construction of the evaporator and the hydro-accumulator, and these differences lead to very distinct operating characteristics for each loop. This paper presents comparisons of the two loops from an...
Topics: AERODYNAMIC CHARACTERISTICS, EMERGENCIES, FAULT DETECTION, FLIGHT CHARACTERISTICS, FLIGHT...
A small-scale laboratory magnetic suspension system, the Large Angle Magnetic Suspension Test Fixture (LAMSTF) has been constructed at NASA Langley Research Center. This paper first presents some recent developments in the mathematical modelling of the system, particularly in the area of eddy current effects. It is shown that these effects are significant, but may be amenable to modelling and measurement. Next, a theoretical framework is presented, together with a comparison of computed and...
Topics: NASA Technical Reports Server (NTRS), DYNAMIC CONTROL, DYNAMIC MODELS, MAGNETIC SUSPENSION, EDDY...
This paper presents the complete forward and inverse kinematics solutions for control of the three degree-of-freedom (DOF) double octahedral variable geometry truss (VGT) module as an extensible gimbal. A VGT is a truss structure partially comprised of linearly actuated members. A VGT can be used as joints in a large, lightweight, high load-bearing manipulator for earth- and space-based remote operations, plus industrial applications. The results have been used to control the NASA VGT hardware...
Topics: NASA Technical Reports Server (NTRS), GIMBALS, INVERSE KINEMATICS, MANIPULATORS, TRUSSES, VARIABLE...
The vaporizer dynamic control characteristics of a 30-cm diameter mercury ion thruster were determined by operating the thruster in an open loop steady state mode and then introducing a small sinusoidal signal on the main, cathode, or neutralizer vaporizer current and observing the response of the beam current, discharge voltage, and neutralizer keeper voltage, respectively. This was done over a range of frequencies and operating conditions. From these data, Bode plots for gain and phase were...
Topics: NASA Technical Reports Server (NTRS), DYNAMIC CHARACTERISTICS, DYNAMIC CONTROL, ION PROPULSION,...
The mechanisms that underlie the circadian variations in electrolyte content in body fluid compartments were investigated, and the mechanisms that control the oscillations were studied in order to investigate what effects internal desynchronization in such a system would have during manned space flight. The studies were performed using volunteer human subjects and squirrel monkeys. The intercompartmental distribution of potassium was examined when dietary intake, activity, and posture are held...
Topics: NASA Technical Reports Server (NTRS), BODY COMPOSITION (BIOLOGY), CIRCADIAN RHYTHMS, DYNAMIC...
An overview of a mechanical rotor control design is presented. Operation at constant RPM and rapid response are obtained by using blade pitch moments for both sensing control need and blade pitch actuation. The basic concept, static or equilibrium design, and dynamic analysis are briefly presented.
Topics: NASA Technical Reports Server (NTRS), ATTITUDE CONTROL, DYNAMIC CONTROL, ROTOR BLADES...
This report is a summary of work done under Grant NAG1-946 for the period 19 December 1988 through 15 August 1992. Most of the technical work is described in the paper produced, including the NASA Contractor Report 4393 - 'Optimal Control Problems with Switching Points'. In the following pages we present a list of the papers along with a brief abstract. The technical work during the last months of the grant has not yet been submitted for publication so we present a summary of that work in an...
Topics: NASA Technical Reports Server (NTRS), DYNAMIC CONTROL, FEEDBACK CONTROL, GUIDANCE (MOTION), OPTIMAL...
Relationships between observers, Kalman Filters and dynamic compensators using feedforward control theory are investigated. In particular, the relationship, if any, between the dynamic compensator state and linear functions of a discrete plane state are investigated. It is shown that, in steady state, a dynamic compensator driven by the plant output can be expressed as the sum of two terms. The first term is a linear combination of the plant state. The second term depends on plant and...
Topics: NASA Technical Reports Server (NTRS), COMPENSATORS, DYNAMIC CONTROL, FEEDFORWARD CONTROL, KALMAN...
