On the design of optimal constrained dynamic compensators for linear constant systems
Optimal fixed dimensionality dynamic compensator design for linear time-invariant closed-loop system based on quadratic cost and gain criteria
Athans, M.↗
SEARCH · Engineering Papers
Results for “closed loop”
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.
MITNYS - A hybrid program for on-line analysis of nystagmus
Hybrid computer program for data reduction or on-line analysis of nystagmus during closed loop experiment involving visual and/or vestibular function
Tole, J. R.↗
Stability conditions for a class of distributed-parameter systems
Distributed parameter systems with transfer function as ratio of output and input multiple transforms, deriving open and closed loop stability criteria
Khatri, H. C.↗
On the minimax reachability of target sets and target tubes
Closed-loop control of discrete time systems with uncertainty, discussing minimax reachability of target sets and tubes
Bertsekas, D. P.↗
180-day life test of solid electrolyte system for oxygen regeneration
Closed-loop solid electrolyte oxygen regeneration life support system, discussing 180-day life test
Elikan, L.↗
Analytic design of digital flight controllers to realize aircraft flying quality specifications
Discrete time digital flight control systems design resulting in closed loop aircraft response characteristics approximation to prescribed flying quality specifications
Montgomery, R. C.↗
Tracking via feedback for systems with irrational transfer function
Optimal tracking feedback filter for closed loop systems with irrational transfer function, using heuristic method
Freedman, M. I.↗
Variable sweep-rate frequency response and vibration testing
Variable sweep rate frequency response and vibration testing for test time reduction, using closed loop controller for sweep rate modulation
Lorenzo, C. F.↗
Spacecraft oxygen recovery system
Spacecraft closed loop oxygen recovery system using electrochemical carbon dioxide concentrator, Sabatier reactor and water electrolysis subsystem
Quattrone, P. D.↗
Cell for electrolysis of water vapor
Electrolytic cells regenerate oxygen from the water vapor in the air of closed-loop life-support system and remove water vapor from air circulated through them. Water is converted into oxygen and hydrogen; the oxygen is returned to the air, the hydrogen is vented or used elsewhere.
Celino, V. A.↗
Aircrew oxygen system
Closed-loop rebreather system which includes pilot provides oxygen for use in aircraft by safe, reliable method of low weight and size and reduces expense of ground equipment. Water electrolysis generated oxygen is fed into rebreather loop which allows nitrogen elimination and water and carbon dioxide removal.
Babinsky, A. D.↗
Visual sensitivity tester
Testing device uses closed loop film cassettes to project programmed visual stimuli on screen which the observer views through a lens making the stimuli appear to be at optical infinity. Tester is useful for determining changes in glautomatous visual field sensitivity.
Haines, R. F.↗
Counter lung
Counter lung, incorporated in closed-loop rebreathing system, accommodates user's breathing tidal volume so that the loop pressure is relatively constant during breathing cycles.
Babinsky, A. D.↗
The theoretical and experimental investigations on multiple pure tone noise, part 1
A theoretical and experimental investigation is described on multiple pure tone noise. Based on a two-dimensional and inviscid flow model, an analysis is developed to predict the generation and subsequent evolution of multiple pure tone noise from prescribed blade-to-blade nonuniformities in the rotor geometry. The results show that even small nonuniformities within manufacturing tolerances can cause a significant amount of multiple pure tone noise. Among the different kinds of nonuniformities investigated, errors in blade spacings are a weaker generator of multiple pure tone noise than errors in blade stagger or blade contours. Experimental investigations of the effects of the rotor relative Mach number, incidence angle and length of the inlet duct on the evolution of the multiple pure tone noise are conducted with a known distribution of rotor nonuniformities. The model fan is operated, in Freon 12, in a closed loop acoustical facility.
Kantola, R. A.↗
On-line digital computer control of the NERVA nuclear rocket engine
The problem of on-line digital computer control of the NERVA nuclear rocket engine is considered. Proposed is a method of State Dependent State Variable Feedback (SDSVF) as a practical approach to the control of NERVA and other complex nonlinear and/or time-varying systems. The difficulties inherent in other design methods are avoided by defining the optimal closed loop system in terms of a desired transfer function, rather than a performance index to maximize or minimize.
Kendrick, L. E.↗
A scanning mirror system for the Apollo telescope mount ultraviolet spectroheliometer
The scanning mirror system described is being developed as the primary mirror in the spectroheliometer. The system consists of a gimbaled mirror mount that is rotated through extremely small angles by the use of frictionless pivots and a closed-loop servo system. Design, fabrication, and test experience are discussed.
Highman, C. O.↗
CMG assembly life test and engineering evaluation test, M-509 experiment
The initial checkout of the control moment gyro system for the astronaut stabilizer maneuvering unit is described, and the test results are presented. The life test proceeded smoothly to its completion, and problem areas encountered in the engineering tests are described. These tests included command rate and torquer current transfer, cage and lock, static inverter and signal noise, dynamic response, closed loop drift rate, and gimbal disturbance torque evaluation tests.
Cramer, P. S.↗
Terminal-Area Guidance Algorithms for Automated Air-Traffic Control
Terminal-area guidance problems are solved in the form of computer-oriented algorithms. A flyable, three-dimensional trajectory is constructed that begins at the current aircraft position, heading, speed, and altitude, and that terminates at a prescribed position, heading, speed, altitude, and time. The terminal position is a waypoint and the terminal time is the assigned landing slot. The algorithms developed are applicable to all possible combinations of initial and final conditiions, and thus can be used in a closed-loop feedback law.
Erzberger, H.↗